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  • 51.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Silvia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Wikehult, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Patient Experience of an 18F-FDG-PET/CT Examination:: Need for Improvements in Patient Care2015In: Journal of Radiology Nursing, ISSN 1546-0843, Vol. 34, no 2, p. 100-108Article in journal (Refereed)
    Abstract [en]

    The aims of this study were to investigate the patients' knowledge about and experience of an 18F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) examination and to investigate the self-reported feelings of stress, level of physical activity, and health-related quality of life (HRQoL) and to find out if this was related to how they experienced the examination. A cross-sectional survey was used to collect information on 198 patients with known or suspected malignancy. As many as 32% to 63% were satisfied with the nursing staff, the communication, and the professional skills. Most patients did not know beforehand what an FDG-PET/CT examination was. The HRQoL, level of perceived stress, and physical activity were relatively low. A better HRQoL, lower level of perceived stress, and a higher level of physical activity were correlated to a more positive experience and higher education to more knowledge about the examination (p < .01–.05). The information before the examination needs to be improved. The results may be used to improve patient care and optimize imaging procedures.

  • 52.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Silvia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Assessment of Whether Patients' Knowledge, Satisfaction, and Experience Regarding Their 18F-Fluoride PET/CT Examination Affects Image Quality2016In: Journal of Nuclear Medicine Technology, ISSN 0091-4916, E-ISSN 1535-5675, Vol. 44, no 1, p. 21-25Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate patients’ previous knowledge, satisfaction and experience regarding a (18F)-fluoride positron emission tomography / computed tomography examination ((18F)-fluoride PET/CT) and to explore whether experienced discomfort during the examination or pain was associated with reduced image quality. A further aim was to explore whether patients’ health-related quality of life (HRQoL) was associated with their satisfaction and experiences of the examination.

    Methods: Fifty consecutive patients with a histopathological diagnosis of prostate cancer who were scheduled for (18F)-fluoride PET/CT were asked to participate in the study, which was performed between November 2011 and April 2013. A questionnaire was used to collect information regarding the patients’ previous knowledge and experience of the examination. Image quality assessment was performed according to an arbitrary scale. The EORTC-QLQ-C30 and QLQ-PR25 were used to assess HRQoL.

    Results: Forty-six patients (96%) completed the questionnaires. Twenty-six per cent of participants did not know at all what a (18F)-fluoride PET/CT examination was. The majority (52-70%) were to a very high degree satisfied with the care provided by the nursing staff but less satisfied with the information given prior to the examination. The image quality was similar in patients who were exhausted or claustrophobic during the examination and those who were not. No correlations between HRQoL and the participants’ experience of (18F)-fluoride PET/CT were found.

    Conclusion: The majority of participants were satisfied with the care provided by the nursing staff, but there is still room for improvement especially regarding the information prior to the examination. Long examination time may be strenuous, for the patient but there was no difference in image quality between patients who felt discomfort during the examination or pain and those who did not.

  • 53.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Röing, Marta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Health Services Research.
    Ehrsson, Ylva Tiblom
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Caring Sciences. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Otolaryngology and Head and Neck Surgery.
    Johansson, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences, Lifestyle and rehabilitation in long term illness. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Clinical Psychology in Healthcare.
    It's a question of endurance: patients with head and neck cancer experiences of 18F-FDG PET/CT in a fixation mask2017In: European Journal of Oncology Nursing, ISSN 1462-3889, E-ISSN 1532-2122, Vol. 29, p. 85-90, article id S1462-3889(17)30082-0Article in journal (Refereed)
    Abstract [en]

    PURPOSE: This study aimed to explore how patients with head and neck cancer experienced undergoing an (18)F-fluoro-deoxy-glucose positrons emissions tomography/computed tomography ((18)F-FDG PET/CT) examination in a fixation mask.

    METHOD: Interviews were conducted with nine patients with known or suspected head and neck cancer who were scheduled for the examination for the first time. The phenomenological method according to van Manen and his four lifeworld existentials; lived space, lived body, lived time, and lived relation was used to analyse the interviews.

    RESULTS: The thoughts and feelings of the patients during the PET/CT examination varied, some found it very difficult, while others did not. However, for all the patients, it was an experience that required some form of coping to maintain composure for example distraction.

    CONCLUSIONS: PET/CT examnation in a fixation mask may be strenuous for some patients. Patients need more detailed information, including suggestions for coping behaviours, prior to the examination, as well as higher level of support during and after the examination. The results of this study may be used to improve patient care and optimize the procedure of PET/CT examination in a fixation mask.

  • 54.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Trampal Pulido, Carlos
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Effects of web-based information on patient satisfaction and image quality in patients undergoing an 18F-FDG PET/CT examination: a randomized controlled trial2018In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 45, no Suppl 1, p. S783-S784Article in journal (Other academic)
  • 55.
    Andersson, Camilla
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Trampal Pulido, Carlos
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Johansson, Birgitta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Randomized Controlled Trial Examining Effects of Web-Based Information on Patient Satisfaction and Image Quality in 18F-FDG PET/CT Examinations2019In: Journal of Nuclear Medicine Technology, ISSN 0091-4916, E-ISSN 1535-5675, no 1, p. 36-46Article in journal (Refereed)
    Abstract [en]

    Our aim was to compare the effect that having access, versus not having access, to web-based patient information on 18F-FDG PET/CT has on image quality and on patient satisfaction with their care during and knowledge about the examination, as well as to explore whether patients utilized and were satisfied with the web-based information.

    Methods: We recruited 148 patients between October 2015 and December 2016 and randomly assigned them to a standard-care group or an intervention group. Both groups received standard information about the 18F-FDG PET/CT examination, but the intervention group also received access to web-based information. A questionnaire was used to evaluate patient satisfaction with, knowledge about, and discomfort during the examination, and a masked assessment of image quality was conducted.

    Results: Overall satisfaction was high in both groups. The lowest satisfaction was with information about how the patients would receive the results of the examination. More patients in the intervention group than in the standard-care group knew how the 18F-FDG PET/CT examination would be conducted. Descriptive data suggest that image quality was slightly better in the intervention group than in the standard-care group, but none of the outcomes significantly differed between the groups. However, several obstacles were encountered during recruitment that led to insufficient power to detect differences. Also, only 54 of 75 patients (72%) in the intervention group utilized the web-based information. However, those who did utilize the information were satisfied with it and found it helpful.

    Conclusion: The effects of web-based information need to be investigated in a larger sample of patients. Having access to improved information before undergoing 18F-FDG PET/CT may help patients prepare for and undergo the examination. It may also improve image quality. However, this possibility needs to be investigated using image quality as the primary outcome. The results may be used to improve patient information and care and thereby optimize the 18F-FDG PET/CT procedure.

  • 56.
    Andersson, Jacob
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Högberg, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Obstetrics and Reproductive Health Research.
    Wester, Knut
    Thiblin, Ingemar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    Differences in head circumference and neuroimaging characteristics: what can they tell about the aetiologies of infant subdural haematoma?Manuscript (preprint) (Other academic)
    Abstract [en]

    Background Acute (ASDH) and chronic subdural haematoma (CSDH) in infants have been regarded as highly specific for abuse. A recent study showed different risk factors for ASDH and CSDH, indicating that CSDH in many cases was related to external hydrocephalus. 

    Purpose To investigate to what extent external hydrocephalus may explain findings and symptoms interpreted as signs of abusive head trauma. 

    Material and methods Eighty-five infants with ASDH (n=16) and CSDH (n=69) were reviewed with regard to cranio-cortical- (CCW), sino-cortical- (SCW), frontal interhemispheric-(IHW), subarachnoid space width (SSW) and head circumference (HC). In infants with unilateral SDH, the correlation between the contralateral SSW and the ipsilateral CCW and SDH width was calculated. A correlation would imply that the CSDH replaces an already existing extracerebral space.

    Results Infants with CSDH had significantly higher CCW, SCW, IHW and SSW than infants with ASDH (p < 0.05). The ipsilateral CCW (R = 0.92, p < 0.001) and SDH width (R = 0.81, p < 0.01) were correlated to the contralateral SSW. Increased HC was more prevalent in Infants with CSDH (71%) than in infants with ASDH (14%) (p < 0.01). Forty-two infants, all with CSDH, had at least one of CCW, SCW or IHW ≥ 95th percentile. Twenty infants, all with CSDH, had CCW, SCW and IHW > 5 mm and increased HC. 

    Conclusion A significant proportion of infants with CSDH may have external hydrocephalus as an underlying cause and that parts of the widened subarachnoid space in some infants is replaced by a CSDH.

  • 57.
    Andersson, Jacob
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Högberg, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Obstetrics and Reproductive Health Research.
    Wester, Knut
    Department of Clinical Medicine K1, University of Bergen, Bergen, Norway.
    Thiblin, Ingemar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    Different vulnerability profiles in acute compared to chronic subdural haematoma amongst infants with suspected abusive head traumaManuscript (preprint) (Other academic)
    Abstract [en]

    Background: In a register study based on ICD 10 coding, there was a similar vulnerability profile (male sex, preterm and small for gestational age) in infants diagnosed with non-traumatic subdural haematoma (SDH) and infants having SDH with abuse diagnosis. However, ICD-10 does not separate between acute (ASDH) and chronic subdural haematoma (CSDH). 

    Purpose: To determine the vulnerability profile in infants having CSDH and ASDH, respectively. 

    Material and methods: A descriptive review of infants with SDH/hygroma examined by the Swedish National Board of Forensic Medicine between 1994 and 2018. Included cases (n=85) were analysed with regard to possible vulnerability factors. 

    Results: Type of subdural fluid could be determined in 85 of 96 cases. Sixteen infants had ASDH and 69 CSDH. Infants with ASDH had the peak incidence during the first month of life, 56% were male, 6% were premature, 13% were twins and 44% died. In infants with CSDH, the peak incidence occurred during the third month of life, 69% were male, 34% were premature, 12% were twins and 4% died. 

    Conclusion: CSDH, but not ASDH, is associated with factors suggesting non-traumatic pathogenesis, for which reason CSDH and ASDH should be analysed separately to extend the knowledge regarding the aetiology of SDH during infancy.  

     

  • 58.
    Andersson, Jacob
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Högberg, Ulf
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, International Maternal and Child Health (IMCH). Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Obstetrics and Reproductive Health Research.
    Wester, Knut
    Thiblin, Ingemar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Forensic Medicine.
    External Hydrocephalus as a Cause of Infant Subdural Hematoma: Epidemiological and Radiological Investigations of Infants Suspected of Being Abused.2021In: Pediatric Neurology, ISSN 0887-8994, E-ISSN 1873-5150, Vol. 126, p. 26-34, article id S0887-8994(21)00212-5Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Acute subdural hematoma (ASDH) and chronic subdural hematoma (CSDH) in infants have been regarded as highly specific for abuse. Other causes of CSDH have not been investigated in a large population.

    PURPOSE: The purpose of this study was to investigate to what extent external hydrocephalus is present in infants with ASDH and CSDH undergoing evaluation for abuse.

    MATERIAL AND METHODS: Eighty-five infants suspected of being abused, with ASDH (n = 16) or CSDH (n = 69), were reviewed regarding age, risk factor profiles, craniocortical width (CCW), sinocortical width (SCW), frontal interhemispheric width (IHW), subarachnoid space width (SSW), and head circumference (HC). In infants with unilateral subdural hematoma (SDH), correlations between contralateral SSW and ipsilateral CCW and SDH width were investigated.

    RESULTS: Infants with CSDH had significantly lower mortality, were more often premature and male, and had significantly higher CCW, SCW, IHW, and SSW than infants with ASDH (P < 0.05). Ipsilateral CCW (R = 0.92, P < 0.001) and SDH width (R = 0.81, P < 0.01) correlated with contralateral SSW. Increased HC was more prevalent in infants with CSDH (71%) than in infants with ASDH (14%) (P < 0.01). Forty-two infants, all with CSDH, had at least one of CCW, SCW, or IHW ≥95th percentile. Twenty infants, all with CSDH, had CCW, SCW, and IHW >5 mm, in addition to increased HC.

    CONCLUSION: A substantial proportion of infants with CSDH who had been suspected of being abused had findings suggesting external hydrocephalus.

  • 59.
    Andersson, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Water–fat separation in magnetic resonance imaging and its application in studies of brown adipose tissue2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Virtually all the magnetic resonance imaging (MRI) signal of a human originates from water and fat molecules. By utilizing the property chemical shift the signal can be separated, creating water- and fat-only images. From these images it is possible to calculate quantitative fat fraction (FF) images, where the value of each voxel is equal to the percentage of its signal originating from fat. In papers I and II methods for water–fat signal separation are presented and evaluated.

    The method in paper I utilizes a graph-cut to separate the signal and was designed to perform well even for a low signal-to-noise ratio (SNR). The method was shown to perform as well as previous methods at high SNRs, and better at low SNRs.

    The method presented in paper II uses convolutional neural networks to perform the signal separation. The method was shown to perform similarly to a previous method using a graph-cut when provided non-undersampled input data. Furthermore, the method was shown to be able to separate the signal using undersampled data. This may allow for accelerated MRI scans in the future.

    Brown adipose tissue (BAT) is a thermogenic organ with the main purpose of expending chemical energy to prevent the body temperature from falling too low. Its energy expending capability makes it a potential target for treating overweight/obesity and metabolic dysfunctions, such as type 2 diabetes. The most well-established way of estimating the metabolic potential of BAT is through measuring glucose uptake using 18F-fludeoxyglucose (18F-FDG) positron emission tomography (PET) during cooling. This technique exposes subjects to potentially harmful ionizing radiation, and alternative methods are desired. One alternative method is measuring the BAT FF using MRI.

    In paper III the BAT FF in 7-year olds was shown to be negatively associated with blood serum levels of the bone-specific protein osteocalcin and, after correction for adiposity, thigh muscle volume. This may have implications for how BAT interacts with both bone and muscle tissue.

    In paper IV the glucose uptake of BAT during cooling of adult humans was measured using 18F-FDG PET. Additionally, their BAT FF was measured using MRI, and their skin temperature during cooling near a major BAT depot was measured using infrared thermography (IRT). It was found that both the BAT FF and the temperature measured using IRT correlated with the BAT glucose uptake, meaning these measurements could be potential alternatives to 18F-FDG PET in future studies of BAT.

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  • 60.
    Andersson, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Mölndal, Sweden.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Mölndal, Sweden.
    Separation of water and fat signal in whole-body gradient echo scans using convolutional neural networks2019In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 82, no 3, p. 1177-1186Article in journal (Refereed)
    Abstract [en]

    Purpose: To perform and evaluate water–fat signal separation of whole‐body gradient echo scans using convolutional neural networks.

    Methods: Whole‐body gradient echo scans of 240 subjects, each consisting of 5 bipolar echoes, were used. Reference fat fraction maps were created using a conventional method. Convolutional neural networks, more specifically 2D U‐nets, were trained using 5‐fold cross‐validation with 1 or several echoes as input, using the squared difference between the output and the reference fat fraction maps as the loss function. The outputs of the networks were assessed by the loss function, measured liver fat fractions, and visually. Training was performed using a graphics processing unit (GPU). Inference was performed using the GPU as well as a central processing unit (CPU).

    Results: The loss curves indicated convergence, and the final loss of the validation data decreased when using more echoes as input. The liver fat fractions could be estimated using only 1 echo, but results were improved by use of more echoes. Visual assessment found the quality of the outputs of the networks to be similar to the reference even when using only 1 echo, with slight improvements when using more echoes. Training a network took at most 28.6 h. Inference time of a whole‐body scan took at most 3.7 s using the GPU and 5.8 min using the CPU.

    Conclusion: It is possible to perform water–fat signal separation of whole‐body gradient echo scans using convolutional neural networks. Separation was possible using only 1 echo, although using more echoes improved the results.

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  • 61.
    Andersson, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Molndal, Sweden.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Molndal, Sweden.
    Water-fat separation incorporating spatial smoothing is robust to noise2018In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 50, p. 78-83, article id S0730-725X(18)30040-7Article in journal (Refereed)
    Abstract [en]

    PURPOSE: To develop and evaluate a noise-robust method for reconstruction of water and fat images for spoiled gradient multi-echo sequences.

    METHODS: The proposed method performs water-fat separation by using a graph cut to minimize an energy function consisting of unary and binary terms. Spatial smoothing is incorporated to increase robustness to noise. The graph cut can fail to find a solution covering the entire image, in which case the relative weighting of the unary term is iteratively increased until a complete solution is found. The proposed method was compared to two previously published methods. Reconstructions were performed on 16 cases taken from the 2012 ISMRM water-fat reconstruction challenge dataset, for which reference reconstructions were provided. Robustness towards noise was evaluated by reconstructing images with different levels of noise added. The percentage of water-fat swaps were calculated to measure performance.

    RESULTS: At low noise levels the proposed method produced similar results to one of the previously published methods, while outperforming the other. The proposed method significantly outperformed both of the previously published methods at moderate and high noise levels.

    CONCLUSION: By incorporating spatial smoothing, an increased robustness towards noise is achieved when performing water-fat reconstruction of spoiled gradient multi-echo sequences.

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  • 62.
    Andersson, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Lundström, Elin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Engström, Mathias
    GE Healthcare.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Medical.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Medical.
    Estimating the cold-induced brown adipose tissue glucose uptake rate measured by 18F-FDG PET using infrared thermography and water-fat separated MRI2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, article id 12358Article in journal (Refereed)
    Abstract [en]

    Brown adipose tissue (BAT) expends chemical energy to produce heat, which makes it a potential therapeutic target for combating metabolic dysfunction and overweight/obesity by increasing its metabolic activity. The most well-established method for measuring BAT metabolic activity is glucose uptake rate (GUR) measured using 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET). However, this is expensive and exposes the subjects to potentially harmful radiation. Cheaper and safer methods are warranted for large-scale or longitudinal studies. Potential alternatives include infrared thermography (IRT) and magnetic resonance imaging (MRI). The aim of this study was to evaluate and further develop these techniques. Twelve healthy adult subjects were studied. The BAT GUR was measured using 18F-FDG PET during individualized cooling. The temperatures of the supraclavicular fossae and a control region were measured using IRT during a simple cooling protocol. The fat fraction and effective transverse relaxation rate of BAT were measured using MRI without any cooling intervention. Simple and multiple linear regressions were employed to evaluate how well the MRI and IRT measurements could estimate the GUR. Results showed that both IRT and MRI measurements correlated with the GUR. This suggest that these measurements may be suitable for estimating the cold-induced BAT GUR in future studies.

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  • 63.
    Andersson, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Roswall, Josefine
    Hallands Hosp Halmstad, Dept Pediat, Halmstad, Sweden;Univ Gothenburg, Sahlgrenska Acad, Inst Clin Sci, Dept Pediat, Gothenburg, Sweden.
    Kjellberg, Emma
    Univ Gothenburg, Sahlgrenska Acad, Inst Clin Sci, Dept Pediat, Gothenburg, Sweden.
    Ahlström, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Molndal, Sweden.
    Dahlgren, Jovanna
    Univ Gothenburg, Sahlgrenska Acad, Inst Clin Sci, Dept Pediat, Gothenburg, Sweden.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Antaros Med, Molndal, Sweden.
    MRI estimates of brown adipose tissue in children - Associations to adiposity, osteocalcin, and thigh muscle volume2019In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 58, p. 135-142Article in journal (Refereed)
    Abstract [en]

    Context: Brown adipose tissue is of metabolic interest. The tissue is however poorly explored in children.

    Methods: Sixty-three 7-year old subjects from the Swedish birth-cohort Halland Health and Growth Study were recruited. Care was taken to include both normal weight and overweight children, but the subjects were otherwise healthy. Only children born full term were included. Water-fat separated whole-body MRI scans, anthropometric measurements, and measurements of fasting glucose and levels of energy homeostasis related hormones, including the insulin-sensitizer osteocalcin, were performed. The fat fraction (FF) and effective transverse relaxation time (T-2(star)) of suspected brown adipose tissue in the cervical-supraclavicular-axillary fat depot (sBAT) and the FFs of abdominal visceral (VAT) and subcutaneous adipose tissue (SAT) were measured. Volumes of sBAT, abdominal VAT and SAT, and thigh muscle volumes were measured.

    Results: The FF in the sBAT depot was lower than in VAT and SAT for all children. In linear correlations including sex and age as explanatory variables, sBAT FF correlated positively with all measures of adiposity (p < 0.01), except for VAT FF and weight, positively with sBAT T-2* (p = 0.036), and negatively with osteocalcin (p = 0.017). When adding measures of adiposity as explanatory variables, sBAT FF also correlated negatively with thigh muscle volume (p < 0.01).

    Conclusions: Whole-body water-fat MRI of children allows for measurements of sBAT. The FF of sBAT was lower than that of VAT and SAT, indicating presence of BAT. Future studies could confirm whether the observed correlations corresponds to a hormonally active BAT.

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  • 64. Andreou, Dimitrios
    et al.
    Saetre, Peter
    Milesson Fors, Björn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Ekselius: Psychiatry.
    Nilsson, Björn Mikael
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Ekselius: Psychiatry.
    Kullberg, Joel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Jönsson, Erik Gunnar
    Ebeling Barbier, Charlotte
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Agartz, Ingrid
    Cardiac left ventricular ejection fraction in men and women with schizophrenia on long-term antipsychotic treatment2020In: Schizophrenia Research, ISSN 0920-9964, E-ISSN 1573-2509, Vol. 218, p. 226-232Article in journal (Refereed)
    Abstract [en]

    Patients with schizophrenia exhibit a higher cardiovascular mortality compared to the general population which has been attributed to life-style factors, genetic susceptibility and antipsychotic medication. Recent echocardiographic studies have pointed to an association between clozapine treatment and reduced left ventricular ejection fraction (LVEF), a measure that has been inversely associated with adverse outcomes including all-cause mortality. Cardiovascular magnetic resonance (CMR) is considered the reference method for LVEF measurement. The aim of the present study was to investigate the LVEF in patients with schizophrenia on long-term treatment with antipsychotics and healthy controls. Twenty-nine adult patients with schizophrenia on long-term medication with antipsychotics and 27 age-, sex- and body mass index-matched healthy controls (mean ages 44 and 45 years, respectively) were recruited from outpatient psychiatric clinics in Uppsala, Sweden. The participants were interviewed and underwent physical examination, biochemical analyses, electrocardiogram and CMR. Men with schizophrenia on long-term antipsychotic treatment showed significantly lower LVEF than controls (p = 0.0076), whereas no such difference was evident among women (p = 0.44). Specifically, clozapine-treated male patients had 10.6% lower LVEF than male controls (p = 0.0064), whereas the LVEF was 5.5% below that of controls among male patients treated with non-clozapine antipsychotics (p = 0.047). Among medicated men with schizophrenia, we found significantly lower LVEF compared to healthy individuals, suggesting the need of routine cardiac monitoring in this patient group. This is the first study showing a significant negative association between treatment with non-clozapine antipsychotics and LVEF.

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  • 65.
    Ange Marie, Ingabire
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Mina, Narmashiri
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    För och nackdelar med CT lågdos protokoll: En kvalitativ litteraturstudie2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Antal röntgenundersökningar som utförs med Computer Tomografi (CT) ökar ständigt i sjukvården, vilket har lett till en ökad mängd farlig strålning som patienter och vårdpersonal utsätts för och därmed följer en rad risker. Därför är det eftersträvansvärt att minimera denna stråldos men även bibehålla bildkvalité och diagnostisk säkerhet. Detta kommer dock med en mängd utmaningar som kräver nya tekniker och protokoll. För att dessa ska appliceras korrekt krävs även att den ansvariga vårdpersonalen besitter god kunskap inom området. 

    Syfte: Syfte med denna studie är att beskriva fördelar och nackdelar med lågdos CT (LDCT) vid buk undersökningar.

    Metod: Den systematiska litteraturstudien sammanställer vetenskapliga artiklar från bland annat PubMed vars kvantitativa eller kvalitativa svar anses kunna besvara den kvalitativa frågeställningen. 

    Resultat: Lågdosprotokoll för CT ger i många fall en liknande diagnostisk säkerhet som konventionell CT samtidigt som dosen sänks kraftigt. Dock begränsas effektiviteten av lågdosprotokollen för bukundersökningar i fall där patienten är överviktig och kan ibland inte appliceras alls om de patologiska fenomenen är för små. Överlag överväger fördelarna med lågdos CT dess nackdelar i de flesta fall.

    Slutsats: Resultatet har visat att lågdos CT kan uppnå samma diagnostiska säkerhet som CT undersökningar med standarddos. Vårdpersonal bör dock vara medveten om begränsningarna med lågdosprotokollen för att undvika risken för upprepning av undersökningar. Mer forskning kring ämnet kan potentiellt driva ner stråldosen ytterligare och med bättre kunskap bland personalen kan diagnoser ställas korrekt och risken för strålskador med CT kan minimeras.  

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  • 66.
    Antoni, Gunnar
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Preparative Medicinal Chemistry.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Lindström, Elin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Elgland, Mathias
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry.
    Eriksson, Olof
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Translational PET Imaging.
    Hultström, Michael
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Frithiof, Robert
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Wanhainen, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Vascular Surgery.
    Sigfridsson, Jonathan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Skorup, Paul
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infection medicine.
    Lipcsey, Miklos
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    In Vivo Visualization and Quantification of Neutrophil Elastase in Lungs of COVID-19 Patients: A First-in-Humans PET Study with 11C-NES2023In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 64, no 1, p. 145-148Article in journal (Refereed)
    Abstract [en]

    COVID-19 can cause life-threatening lung-inflammation that is suggested to be mediated by neutrophils, whose effector mechanisms in COVID-19 is inexplicit. The aim of the present work is to evaluate a novel PET tracer for neutrophil elastase in COVID-19 patients and healthy controls.

    METHODS: In this open-label, First-In-Man study, four patients with hypoxia due to COVID-19 and two healthy controls were investigated with positron emission tomography (PET) using the new selective and specific neutrophil elastase PET-tracer [11C]GW457427 and [15O]water for the visualization and quantification of NE and perfusion in the lungs, respectively.

    RESULTS: [11C]GW457427 accumulated selectively in lung areas with ground-glass opacities on computed tomography characteristic of COVID-19 suggesting high levels on NE in these areas. In the same areas perfusion was severely reduced in comparison to healthy lung tissue as measured with [15O]water.

    CONCLUSION: The data suggests that NE may be responsible for the severe lung inflammation in COVID-19 patients and that inhibition of NE could potentially reduce the acute inflammatory process and improve the condition.

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  • 67.
    Antonodimitrakis, Pantelis Clewemar
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Olofsson, Helena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Clinical and experimental pathology.
    Grimelius, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Granberg, Dan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrin Oncology.
    Skogseid, Britt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Neuroendocrine tumors with syndromic vasoactive intestinal polypeptide hypersecretion: a retrospective study2017In: International Journal of Endocrine Oncology, Vol. 4, no 1, p. 9-22Article in journal (Refereed)
    Abstract [en]

    Aim: Vasoactive intestinal polypeptide producing neuroendocrine tumors are rare and cause severe hormonal symptoms. Patients/methods: Eighteen patients with vasoactive intestinal polypeptide producing neuroendocrine tumors were analyzed with reviews of medical records, radiology and tumor tissue specimens. Results: Twelve patients (67%) had liver metastases at diagnosis. Chemotherapy, somatostatin analogs and interferon were given as medical therapies. Streptozocin/5-fluorouracil produced an objective response in 40% of the evaluable patients. Somatostatin analogs gave a clinical/biochemical response in eight out of nine patients. Transarterial embolization of the liver and peptide receptor radionuclide therapy was given to refractory cases. Sixteen patients died during the observation period. The median overall survival from diagnosis was 102 months. Conclusion: Systemic chemotherapy and somatostatin analogs should be given in cases of advanced disease or for hormonal symptoms.

  • 68.
    Antonodimitrakis, Pantelis
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Wassberg, Cecilia
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Granberg, Dan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrin Oncology.
    Skogseid, Britt
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Eriksson, Barbro
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Streptozocin and 5-FU for the treatment of Pancreatic Neuroendocrine Tumors: Efficacy, Prognostic Factors and Toxicity2016In: Neuroendocrinology, ISSN 0028-3835, E-ISSN 1423-0194, Vol. 103, no 3-4, p. 345-353Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: In our center, the combination of streptozocin (STZ) and 5-fluorouracil (5-FU) has been used as the first-line treatment in the majority of patients with pancreatic neuroendocrine tumors (pNETs) over the past few decades. The objective of the current study was to assess the efficacy, prognostic factors and safety of the combination of STZ and 5-FU.

    PATIENTS AND METHODS: Medical records and radiological reports of 133 patients with pNETs who received the combination of STZ and 5-FU during the period 1981-2014 were retrospectively evaluated.

    RESULTS: Median survival from start of treatment was 51.9 months in the whole group. In the radiologically evaluable patients (n = 100) progression-free survival was 23 months. Complete response was reached in 3 patients (3%), partial response in 25 patients (25%), 64 patients (64%) had stable disease and 8 patients (8%) had progressive disease. In a multivariate analysis, surgery of the primary tumor and having a G3 tumor were significant positive and negative prognostic factors of survival from start of treatment, respectively. Having either a G3 tumor or stage IV tumor were significant prognostic factors for shorter progression-free survival. Chemotherapy had to be discontinued in 29 patients due to side-effects, of which kidney toxicity (mainly grade 1-2) was the most frequent.

    CONCLUSION: As shown in recent reports, the combination of STZ and 5-FU is effective in the treatment of pNETs in terms of survival and radiological response, and has an acceptable toxicity profile.

  • 69.
    Appel, Lieuwe
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Jonasson, My
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Danfors, Torsten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Nyholm, Dag
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Neurology.
    Askmark, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Neurology.
    Lubberink, Mark
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science, Section of Nuclear Medicine and PET. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Use of C-11-PE2I PET in Differential Diagnosis of Parkinsonian Disorders2015In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 56, no 2, p. 234-242Article in journal (Refereed)
    Abstract [en]

    In idiopathic Parkinson disease and atypical parkinsonian disorders, central dopaminergic and overall brain functional activity are altered to different degrees, causing difficulties in achieving an unambiguous clinical diagnosis. A dual examination using I-123-FP-CIT (I-123-N-omega-fluoropropyl- 2 beta-carbomethoxy-3 beta-(4-iodophenyl) nortropane, or I-123-ioflupane) SPECT and F-18-FDG PET provides complementary information on dopamine transporter (DAT) availability and overall brain functional activity, respectively. Parametric images based on a single, dynamic C-11-PE2I (N-(3-iodoprop-2E-enyl)-2 beta-carbomethoxy-3 beta-(4-methyl-phenyl) nortropane) scan potentially supply both DAT availability (nondisplaceable binding potential [BPND]) and relative cerebral blood flow (relative delivery [R-1]) at voxel level. This study aimed to evaluate the validity of C-11-PE2I PET against the dual-modality approach using I-123-FP-CIT SPECT and F-18-FDG PET.

    Methods: Sixteen patients with parkinsonian disorders had a dual examination with F-18-FDG PET and I-123-FP-CIT SPECT following clinical routines and additionally an experimental C-11-PE2I PET scan. Parametric BPND and R-1 images were generated using receptor parametric mapping with the cerebellum as a reference. T1-weighted MR imaging was used for automated definition of volumes of interest (VOI). The DAT VOIs included the basal ganglia, whereas the overall brain functional activity was examined using VOIs across the brain. BPND and R-1 values were compared with normalized I-123-FP-CIT and F-18-FDG uptake values, respectively, using Pearson correlations and regression analyses. In addition, 2 masked interpreters evaluated the images visually, in both the routine and the experimental datasets, for comparison of patient diagnoses.

    Results: Parametric C-11-PE2I BPND and R-1 images showed high consistency with I-123-FP-CIT SPECT and F-18-FDG PET images. Correlations between C-11-PE2I BPND and I-123-FP-CIT uptake ratios were 0.97 and 0.76 in the putamen and caudate nucleus, respectively. Regional C-11-PE2I R-1 values were moderately to highly correlated with normalized F-18-FDG values (range, 0.61-0.94). Visual assessment of DAT availability showed a high consistency between C-11-PE2I BPND and I-123-FP-CIT images, whereas the consistency was somewhat lower for appraisal of overall brain functional activity using I-123-FP-CIT and F-18-FDG images. Substantial differences were found between clinical diagnosis and both neuro-imaging diagnoses.

    Conclusion: A single, dynamic C-11-PE2I PET investigation is a powerful alternative to a dual examination with I-123-FP-CIT SPECT and F-18-FDG PET for differential diagnosis of parkinsonian disorders. A large-scale patient study is, however, needed to further investigate distinct pathologic patterns in overall brain functional activity for various parkinsonian disorders.

  • 70.
    Arcos Qvarnström, Ronja
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Bonde Kalén, Matilda
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Patienters upplevelse av information i samband med en 18F-FDG PET/DT-undersökning: En kvantitativ enkätstudie2024Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nuclear Medicine is a speciality in which Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a common examination. The most common indication for undergoing the examination is known or suspected cancer. Aim: Our aim was to study patients’ experiences regarding the information during an 18F-FDG PET/CT examination. Method: A quantitative cross-sectional study was carried out at the Nuclear Medicine department in which 100 patients who met the inclusion criteria were asked to participate. The participants were asked to answer a questionnaire regarding the information containing of nine study-specific questions with five options. Results: The results of our study showed that 93,4% of the participants perceived the written information as direct and easily comprehensible. All questions received a median score of 4, which corresponds with alternative 5 “Strongly agree”. The result shows that 86 participants (94,5%) were satisfied with the verbal information and that 78 participants (88,7%) were satisfied with the written information. The results showed that the information regarding the radioactive isotope received 7 “Disagree” and the information after the examination received 3 “Strongly disagree”. Conclusion: The majority of patients who undergo an 18F-FDG PET/CT examination are satisfied with the information during the examination. However, the information regarding the radioactive tracer and the information after the examination needs to be improved. A larger study that includes more participants over a longer period of time is suggested to be conducted for more generalized results.

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    Patienters upplevelse av information i samband med en 18F-FDG PET/DT-undersökning
  • 71.
    Arvanitis, Panagiotis
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia. Uppsala University Hospital.
    Johannson, Anna-Karin
    Frick, Mats
    Malmborg, Helena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia. Uppsala University Hospital.
    Gerovasileiou, Spyridon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University Hospital.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Uppsala University Hospital.
    Blomström-Lundqvist, Carina
    Uppsala University Hospital.
    Serial Magnetic Resonance Imaging after Electrical Cardioversion of Recent Onset Atrial Fibrillation in Anticoagulant-Naïve Patients –: A Prospective Study Exploring Clinically Silent Cerebral Lesions2020In: Journal of Atrial Fibrillation, ISSN 1941-6911, Vol. 13, no 2Article in journal (Refereed)
  • 72.
    Arvanitis, Panagiotis
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Johansson, A. K.
    Frick, Mats
    Malmborg, Helena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Gerovasileiou, Spyridon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Blomström-Lundqvist, Carina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Timing and degree of left atrial stunning and reverse functional remodeling following electrical cardioversion in patients with recent onset atrial fibrillation2020In: European Heart Journal, Supplement, ISSN 1520-765X, E-ISSN 1554-2815, Vol. 41, no Supplement_2, article id ehaa946.0465Article in journal (Other academic)
    Abstract [en]

    Background

    Atrial fibrillation (AF) results in left atrial electrical, structural and functional remodeling. Restoration of sinus rhythm hallmarks the beginning of reverse remodeling, the extent of which may depend on the type of AF.

    Purpose

    The aim of the study was to assess resumption of left atrial function after electric cardioversion in patients with recent onset AF and to explore the association between reverse remodeling and the type of atrial fibrillation.

    Methods

    Patients with AF duration <48 hours were prospectively included. Trans-thoracic echocardiography was performed prior, immediately after (2–4 hours) and 7–10 days following CV. Left atrial volume index (LAVI), left atrial global longitudinal strain during reservoir (LAGLS-res), conduit (LAGLS-cond) and contractile (LAGLS-contr) phases, left atrial ejection fraction (LAEF) and left ventricular ejection fraction (LVEF) were measured.

    Results

    Forty-three patients (84% males) aged 55±9.6 years, (mean±SD), with median CHA2DS2-VASc score 1 (interquartile range 0–1) were included. Repeated measure analysis of variance revealed a statistically significant overall change for LAGLS-res F(2,78)=55.4, p<0,001, LAGLS-cond F(2,78)=23.3, p<0,001, LAGLS-contr F(2,78)=39.7, p<0,001, LAEF F(2,80)=28.5, p<0.001 and LVEF F(2,80)=8.4, p<0.001. At 7–10 days, LAGLS-contr 12±4%, LAEF 53±9% and LVEF 60±6 (mean±SD) return within normal reference intervals. Notably left atrial recovery seems to precede left ventricular recovery. No statistical significant interaction with the type of atrial fibrillation could be shown.

    Conclusion

    Left atrial functional reverse remodeling occurs within ten days after successful electric cardioversion of patients with recent onset atrial fibrillation.

  • 73.
    Arvanitis, Panagiotis
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Johansson, Anna-Karin
    Frick, Mats
    Malmborg, Helena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Gerovasileiou, Spyridon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Larsson, Elna-Marie
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Blomström-Lundqvist, Carina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia.
    Recent-onset atrial fibrillation: a study exploring the elements of Virchow's triad after cardioversion2022In: Journal of Interventional Cardiac Electrophysiology, ISSN 1383-875X, E-ISSN 1572-8595, Vol. 64, no 1, p. 49-58Article in journal (Refereed)
    Abstract [en]

    Purpose

    Atrial fibrillation (AF) imposes an inherent risk for stroke and silent cerebral emboli, partly related to left atrial (LA) remodeling and activation of inflammatory and coagulation systems. The aim was to explore the effects of cardioversion (CV) and short-lasting AF on left atrial hemodynamics, inflammatory, coagulative and cardiac biomarkers, and the association between LA functional recovery and the presence of a prior history of AF.

    Methods

    Patients referred for CV within 48 h after AF onset were prospectively included. Echocardiography and blood sampling were performed immediately prior, 1–3 h after, and at 7–10 days after CV. The presence of chronic white matter hyperintensities (WMH) on magnetic resonance imaging was related to biomarker levels.

    Results

    Forty-three patients (84% males), aged 55±9.6 years, with median CHA2DS2-VASc score 1 (IQR 0–1) were included. The LA emptying fraction (LAEF), LA peak longitudinal strain during reservoir, conduit, and contractile phases improved significantly after CV. Only LAEF normalized within 10 days. Interleukin-6, high-sensitivity cardiac-troponin-T (hs-cTNT), N-terminal-pro-brain-natriuretic peptide, prothrombin-fragment 1+2 (PTf1+2), and fibrinogen decreased significantly after CV. There was a trend towards higher C-reactive protein, hs-cTNT, and PTf1+2 levels in patients with WMH (n=21) compared to those without (n=22). At 7–10 days, the LAEF was significantly lower in patients with a prior history of AF versus those without.

    Conclusion

    Although LA stunning resolved within 10 days, LAEF remained significantly lower in patients with a prior history of AF versus those without. Inflammatory and coagulative biomarkers were higher before CV, but subsided after 7–10 days, which altogether might suggest an enhanced thrombogenicity, even in these low-risk patients.

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  • 74.
    Asplund, Teo
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Luengo Hendriks, Cris L.
    Flagship Biosciences Inc, Colorado, USA..
    Thurley, Matthew J.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Estimating the Gradient for Images with Missing Samples Using Elliptical Structuring ElementsIn: Article in journal (Refereed)
  • 75.
    Asplund, Teo
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Serna, Andrés
    Terra3D.
    Marcotegui, Beatriz
    MINES ParisTech, PSL Research University, CMM - Centre for Mathematical Morphology.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Luengo Hendriks, Cris L.
    Flagship Biosciences Inc..
    Mathematical Morphology on Irregularly Sampled Data Applied to Segmentation of 3D Point Clouds of Urban Scenes2019In: International Symposium on Mathematical Morphology and Its Applications to Signal and Image Processing, Springer Nature , 2019Conference paper (Refereed)
    Abstract [en]

    This paper proposes an extension of mathematical morphology on irregularly sampled signals to 3D point clouds. The proposed method is applied to the segmentation of urban scenes to show its applicability to the analysis of point cloud data. Applying the proposed operators has the desirable side-effect of homogenizing signals that are sampled heterogeneously. In experiments we show that the proposed segmentation algorithm yields good results on the Paris-rue-Madame database and is robust in terms of sampling density, i.e. yielding similar labelings for more sparse samplings of the same scene.

  • 76.
    Axbåge, Daniel
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Werner, Johanna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Mobil Radiologi: Radiologins Roll i Samhället2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 77.
    Ayyalasomayajula, Kalyan Ram
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction.
    Wilkinson, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Malmberg, Filip
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Brun, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction.
    CalligraphyNet: Augmenting handwriting generation with quill based stroke width2019Manuscript (preprint) (Other academic)
    Abstract [en]

    Realistic handwritten document generation garners a lot ofinterest from the document research community for its abilityto generate annotated data. In the current approach we haveused GAN-based stroke width enrichment and style transferbased refinement over generated data which result in realisticlooking handwritten document images. The GAN part of dataaugmentation transfers the stroke variation introduced by awriting instrument onto images rendered from trajectories cre-ated by tracking coordinates along the stylus movement. Thecoordinates from stylus movement are augmented with thelearned stroke width variations during the data augmentationblock. An RNN model is then trained to learn the variationalong the movement of the stylus along with the stroke varia-tions corresponding to an input sequence of characters. Thismodel is then used to generate images of words or sentencesgiven an input character string. A document image thus cre-ated is used as a mask to transfer the style variations of the inkand the parchment. The generated image can capture the colorcontent of the ink and parchment useful for creating annotated data.

  • 78.
    Back, Anna-Karin
    et al.
    Örebro Univ, Fac Hlth Sci, Dept Radiol, Örebro, Sweden..
    Savvopoulos, Christos
    Örebro Univ, Fac Med & Hlth, Dept Radiol, Örebro, Sweden..
    Kero, Tanja
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Gryback, Per
    Karolinska Inst, Karolinska Univ Hosp, Dept Nucl Med, Dept Mol Med & Surg, Stockholm, Sweden..
    Geijer, Hakan
    Örebro Univ, Fac Med & Hlth, Dept Radiol, Örebro, Sweden..
    Renography with a semiautomated algorithm for diuretic decision 7 min postradiopharmaceutical administration: a feasibility study2020In: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 41, no 10, p. 1018-1025Article in journal (Refereed)
    Abstract [en]

    Objective The F+10 method for diuretic renography (diuretics given 10 min after the radiopharmaceutical) could be a time-conserving method. This method involves a 30-min dynamic acquisition where diuretics are administered only when necessary by the Nuclear Medicine technologist performing the examination. The purpose of this study was to assess the method's performance and to discover the optimal threshold of residual activity for a diuretic administration 7 min into the F+10 renography by reprocessing raw data from prior performed examinations with 20-min acquisitions without diuretics. Methods Retrospectively, raw data from 320 original examinations of adult patients performed from 2013 to 2015 were reprocessed into 7-min series and categorized as requiring diuretic or not. The diuretic decisions made by an expert panel were used as a reference. A receiver-operating characteristic curve was drawn to assess the optimal cutoff value for the residual renal activity. Sensitivity, specificity, positive and negative predictive values, as well as the Youden J index were calculated. Result The experts classified 50% (160 examinations) as in need of diuretics. The receiver-operating characteristic curve demonstrated the theoretical optimal cutoff value at 7 min to be 94% of maximum activity (sensitivity 0.93, specificity 0.81, Youden J index 0.73). A clinically acceptable threshold is suggested to be 85% (sensitivity 0.99, specificity 0.59, Youden J index 0.58). Conclusion Tc-99m-mercaptoacetyltriglycine renography with the F+10 method and the threshold 85% for diuretic decision 7 min into the renography is a feasible and acceptable method in clinical practice.

  • 79. Backman, Samuel
    et al.
    Botling, Johan
    Nord, Helena
    Ghosal, Suman
    Stålberg, Peter
    Juhlin, C Christofer
    Almlöf, Jonas
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Zhang, Liang
    Moens, Lotte
    Eriksson, Barbro
    Welin, Staffan
    Hellman, Per
    Skogseid, Britt
    Pacak, Karel
    Mollazadegan, Kazhan
    Åkerström, Tobias
    Crona, Joakim
    The Evolutionary History of Metastatic Pancreatic Neuroendocrine Tumours Reveals a Therapy Driven Route to High-Grade Transformation.2024In: medRxiv : the preprint server for health sciences, article id 2024.01.08.24300723Article in journal (Refereed)
    Abstract [en]

    Tumour evolution with acquisition of more aggressive disease characteristics is a hallmark of disseminated cancer. Metastatic pancreatic neuroendocrine tumours (PanNETs) in particular, show frequent progression from a low/intermediate to a high-grade disease. To understand the molecular mechanisms underlying this phenomenon, we performed multi-omics analysis of 32 longitudinal samples from six metastatic PanNET patients. Following MEN1 inactivation, PanNETs exhibit genetic heterogeneity on both spatial and temporal dimensions with parallel and convergent tumuor evolution involving the ATRX/DAXX and mTOR pathways. Following alkylating chemotherapy treatment, some PanNETs develop mismatch repair deficiency and acquire a hypermutator phenotype. This DNA hypermutation phenotype was only found in cases that also showed transformation into a high-grade PanNET. Overall, our findings contribute to broaden the understanding of metastatic PanNET, and suggests that therapy driven disease evolution is an important hallmark of this disease.

  • 80.
    Badoud, Simon
    et al.
    Univ Hosp Geneva, Neurol Unit, Dept Clin Neurosci, Geneva, Switzerland.;Univ Fribourg CH, Neurophysiol Unit, Dept Med, Fribourg, Switzerland.;Univ Geneva, Fac Med, Geneva, Switzerland..
    Nicastro, Nicolas
    Univ Hosp Geneva, Neurol Unit, Dept Clin Neurosci, Geneva, Switzerland.;Univ Geneva, Fac Med, Geneva, Switzerland..
    Garibotto, Valentina
    Univ Geneva, Fac Med, Geneva, Switzerland.;Geneva Univ Hosp, Nucl Med & Mol Imaging Unit, Dept Med Imaging, Geneva, Switzerland..
    Burkhard, Pierre R.
    Univ Hosp Geneva, Neurol Unit, Dept Clin Neurosci, Geneva, Switzerland.;Univ Geneva, Fac Med, Geneva, Switzerland..
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Univ Geneva, Fac Med, Geneva, Switzerland.;Ctr Diagnost Radiolog Carouge, Geneva, Switzerland.;Univ Hosp Freiburg, Dept Neuroradiol, Freiburg, Germany..
    Distinct spatiotemporal patterns for disease duration and stage in Parkinson's disease2016In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 43, no 3, p. 509-516Article in journal (Refereed)
    Abstract [en]

    Purpose To assess correlations between the degree of dopaminergic depletion measured using single-photon emission computed tomography (SPECT) and different clinical parameters of disease progression in Parkinson's disease (PD). Methods This retrospective study included 970 consecutive patients undergoing I-123-ioflupane SPECT scans in our institution between 2003 and 2013, from which we selected a study population of 411 patients according to their clinical diagnosis: 301 patients with PD (69.4 +/- 11.0 years, of age, 163 men) and 110 patients with nondegenerative conditions included as controls (72.7 +/- 8.0 years of age, 55 men). Comprehensive and operator-independent data analysis included spatial normalization into standard space, estimation of the mean uptake values in the striatum (caudate nucleus + putamen) and voxel-wise correlation between SPECT signal intensity and disease stage as well as disease duration in order to investigate the spatiotemporal pattern of the dopaminergic nigrostriatal degeneration. To compensate for potential interactions between disease stage and disease duration, one parameter was used as nonexplanatory coregressor for the other. Results Increasing disease stage was associated with an exponential decrease in I-123-ioflupane uptake (R (2) = 0.1501) particularly in the head of the ipsilateral caudate nucleus (p < 0.0001), whereas increasing disease duration was associated with a linear decrease in I-123-ioflupane uptake (p < 0.0001; R (2) = 0.1532) particularly in the contralateral anterior putamen (p < 0.0001). Conclusion We observed two distinct spatiotemporal patterns of posterior to anterior dopaminergic depletion associated with disease stage and disease duration in patients with PD. The developed operator-independent reference database of 411 I-123-ioflupane SPECT scans can be used for clinical and research applications.

  • 81. Badoud, Simon
    et al.
    Van De Ville, Dimitri
    Nicastro, Nicolas
    Garibotto, Valentina
    Burkhard, Pierre R
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Discriminating among degenerative parkinsonisms using advanced (123)I-ioflupane SPECT analyses2016In: NeuroImage: Clinical, E-ISSN 2213-1582, Vol. 12, p. 234-240Article in journal (Refereed)
    Abstract [en]

    (123)I-ioflupane single photon emission computed tomography (SPECT) is a sensitive and well established imaging tool in Parkinson's disease (PD) and atypical parkinsonian syndromes (APS), yet a discrimination between PD and APS has been considered inconsistent at least based on visual inspection or simple region of interest analyses. We here reappraise this issue by applying advanced image analysis techniques to separate PD from the various APS. This study included 392 consecutive patients with degenerative parkinsonism undergoing (123)I-ioflupane SPECT at our institution over the last decade: 306 PD, 24 multiple system atrophy (MSA), 32 progressive supranuclear palsy (PSP) and 30 corticobasal degeneration (CBD) patients. Data analysis included voxel-wise univariate statistical parametric mapping and multivariate pattern recognition using linear discriminant classifiers. MSA and PSP showed less ioflupane uptake in the head of caudate nucleus relative to PD and CBD, yet there was no difference between MSA and PSP. CBD had higher uptake in both putamen relative to PD, MSA and PSP. Classification was significant for PD versus APS (AUC 0.69, p < 0.05) and between APS subtypes (MSA vs CBD AUC 0.80, p < 0.05; MSA vs PSP AUC 0.69 p < 0.05; CBD vs PSP AUC 0.69 p < 0.05). Both striatal and extra-striatal regions contain classification information, yet the combination of both regions does not significantly improve classification accuracy. PD, MSA, PSP and CBD have distinct patterns of dopaminergic depletion on (123)I-ioflupane SPECT. The high specificity of 84-90% for PD versus APS indicates that the classifier is particularly useful for confirming APS cases.

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  • 82.
    Bajic, Dragan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Kumlien, Eva
    Raininko, Raili
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Incomplete hippocampal inversion does not affect hippocampal volume in neurologically healthy subjects.2017In: Neuroradiology, ISSN 0028-3940, E-ISSN 1432-1920, Vol. Suppl1, p. S31-32Article in journal (Refereed)
  • 83.
    Bajic, Dragan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Kumlien, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Neurology.
    Raininko, Raili
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Incomplete hippocampal inversion in patients with focal epilepsy without known etiology and focal MRI abnormalities.2016In: Neuroradiology Vol 58: Suppl.1, Springer, 2016, Vol. 58, p. S21-Conference paper (Refereed)
    Abstract [en]

    Incomplete hippocampal inversion in patients with focal epilepsy without known etiology and focal MRI abnormalities

    PURPOSE: Incomplete hippocampal inversion (IHI) is more common in patients with epilepsy than in subjects without epilepsy but is probably not an etiological factor. IHI frequency varies in different types of epilepsy. Our purpose was to evaluate the hippocampi of patients having focal epilepsy with unknown etiology and without focal abnormalities on MRI (EPue).

    METHODS: MRIs of 58 patients with EPue and 147 neurologically healthy controls were evaluated. Hippocampal volumetry could be performed in 54 of the patients. 47 controls, preferably those having IHI, were chosen for volumetry. The findings were compared with seizure semiology and EEG findings.

    RESULTS: 30/58 patients (52%) had IHI (18 left, 12 bilateral). 28/147 controls (19%) had IHI (20 left, 8 bilateral) (p<0.001). In subjects studied with volumetry, 27/54 patients (50%) and 23/47 selected controls (49%) had IHI. In patients, IHI was found on the left in 15 and bilaterally in 12. In controls, the numbers were 16 and 5, respectively. The left hippocampus was smaller in 48 patients and in 46 controls.  Asymmetry index (AI) was >0.10 in 16 patients (30%) and in 3 controls (6.5%) (p<0.01).  Among 10 patients having IHI and AI >0.10, six had temporal lobe semiology. One of them had bilateral IHI, 5 had IHI on the left. EEG foci were ipsilateral to IHI in 3, contralateral in 2.

    CONCLUSIONS: IHI was significantly more common in EPue patients than in controls. Hippocampal volume asymmetry was more prominent in the patients. Temporal semiology and EEG focus were not obviously related to IHI.

  • 84.
    Bane, Octavia
    et al.
    Icahn Sch Med Mt Sinai, BioMed Engn & Imaging Inst, New York, NY 10029 USA;Icahn Sch Med Mt Sinai, Dept Radiol, New York, NY 10029 USA.
    Mendichovszky, Iosif A.
    Cambridge Univ Hosp NHS Fdn Trust, Addenbrookes Hosp, Dept Radiol, Cambridge, England.
    Milani, Bastien
    Lausanne Univ Hosp, Ctr BioMed Imaging, Lausanne, Switzerland;Univ Lausanne, Lausanne, Switzerland.
    Dekkers, Ilona A.
    Leiden Univ, Med Ctr, Dept Radiol, Leiden, Netherlands.
    Deux, Jean-Francois
    Grp Hosp Henri Mondor, Dept Radiol, Creteil, France.
    Eckerbom, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Grenier, Nicolas
    Univ Bordeaux, CHU Bordeaux, Dept Radiol, Bordeaux, France.
    Hall, Michael E.
    Univ Mississippi, Med Ctr, Dept Med, Jackson, MS 39216 USA.
    Inoue, Tsutomu
    Saitama Med Univ, Fac Med, Dept Nephrol, Saitama, Japan.
    Laustsen, Christoffer
    Aarhus Univ, Dept Clin Med, MR Res Ctr, Aarhus, Denmark.
    Lerman, Lilach O.
    Mayo Clin, Div Nephrol & Hypertens, Dept Internal Med, Rochester, MN USA.
    Liu, Chunlei
    Univ Calif Berkeley, Elect Engn & Comp Sci, Berkeley, CA 94720 USA;Univ Calif Berkeley, Helen Wills Neurosci Inst, Berkeley, CA 94720 USA.
    Morrell, Glen
    Univ Utah, Dept Radiol & Imaging Sci, Salt Lake City, UT USA.
    Pedersen, Michael
    Aarhus Univ Hosp, Comparat Med Lab, Dept Clin Med, Aarhus, Denmark.
    Pruijm, Menno
    Univ Lausanne, Lausanne, Switzerland;Lausanne Univ Hosp, Nephrol & Hypertens Serv, Lausanne, Switzerland.
    Sadowski, Elizabeth A.
    Univ Wisconsin, Dept Radiol, Sch Med & Publ Hlth, Madison, WI 53706 USA.
    Seeliger, Erdmann
    Charite Univ Med Berlin, Inst Physiol, Berlin, Germany.
    Sharma, Kanishka
    Univ Leeds, Dept Biomed Imaging Sci, Imaging Biomarkers Grp, Leeds, W Yorkshire, England.
    Thoeny, Harriet
    Univ Fribourg, Hop Cantonal Fribourgois, Dept Radiol, Fribourg, Switzerland.
    Vermathen, Peter
    Univ Spital Bern, Inselspital, Dept BioMed Res, Bern, Switzerland;Univ Spital Bern, Inselspital, Dept Radiol, Bern, Switzerland.
    Wang, Zhen J.
    Univ Calif San Francisco, Med Ctr, Dept Radiol & Biomed Imaging, San Francisco, CA USA.
    Serafin, Zbigniew
    Nicolaus Copernicus Univ, Dept Radiol, Coll Med, Bydgoszcz, Poland.
    Zhang, Jeff L.
    Harvard Med Sch, Massachusetts Gen Hosp, Athinoula A Martinos Ctr Biomed Imaging, Boston, MA 02115 USA.
    Francis, Susan T.
    Univ Notthingham, Sir Peter Mansfield Ctr, Notthingham, England.
    Sourbron, Steven
    Univ Leeds, Dept Biomed Imaging Sci, Imaging Biomarkers Grp, Leeds, W Yorkshire, England.
    Pohlmann, Andreas
    Helmholtz Assoc, Max Delbrueck Ctr Mol Med, Berlin Ultrahigh Field Facil, Berlin, Germany.
    Fain, Sean B.
    Univ Wisconsin, Dept Biomed Engn, Madison, WI USA;Univ Wisconsin, Dept Radiol, Madison, WI 53706 USA;Univ Wisconsin, Dept Med Phys, 1530 Med Sci Ctr, Madison, WI 53706 USA.
    Prasad, Pottumarthi V.
    NorthShore Univ Hlth Syst, Ctr Adv Imaging, Dept Radiol, Evanston, IL USA.
    Consensus-based technical recommendations for clinical translation of renal BOLD MRI2020In: Magnetic Resonance Materials in Physics, Biology and Medicine, ISSN 0968-5243, E-ISSN 1352-8661, Vol. 33, no 1, p. 199-215Article, review/survey (Refereed)
    Abstract [en]

    Harmonization of acquisition and analysis protocols is an important step in the validation of BOLD MRI as a renal biomarker. This harmonization initiative provides technical recommendations based on a consensus report with the aim to move towards standardized protocols that facilitate clinical translation and comparison of data across sites. We used a recently published systematic review paper, which included a detailed summary of renal BOLD MRI technical parameters and areas of investigation in its supplementary material, as the starting point in developing the survey questionnaires for seeking consensus. Survey data were collected via the Delphi consensus process from 24 researchers on renal BOLD MRI exam preparation, data acquisition, data analysis, and interpretation. Consensus was defined as >= 75% unanimity in response. Among 31 survey questions, 14 achieved consensus resolution, 12 showed clear respondent preference (65-74% agreement), and 5 showed equal (50/50%) split in opinion among respondents. Recommendations for subject preparation, data acquisition, processing and reporting are given based on the survey results and review of the literature. These technical recommendations are aimed towards increased inter-site harmonization, a first step towards standardization of renal BOLD MRI protocols across sites. We expect this to be an iterative process updated dynamically based on progress in the field.

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  • 85.
    Banerjee, Subhashis
    et al.
    Machine Intelligence Unit Indian Statistical Institute Kolkata, India.
    Kumar Dhara, Ashis
    National Institute of Technology, Durgapur, West Bengal, India.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Visual Information and Interaction. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Segmentation of Intracranial Aneurysm Remnant in MRA using Dual-Attention Atrous Net2021In: 25th International Conference on Pattern Recognition (ICPR), 2021, p. 9265-9272Conference paper (Refereed)
    Abstract [en]

    Due to the advancement of non-invasive medical imaging modalities like Magnetic Resonance Angiography (MRA), an increasing number of Intracranial Aneurysm (IA) cases are being reported in recent years. The IAs are typically treated by so-called endovascular coiling, where blood flow in the IA is prevented by embolization with a platinum coil. Accurate quantification of the IA Remnant (IAR), i.e. the volume with blood flow present post treatment is the utmost important factor in choosing the right treatment planning. This is typically done by manually segmenting the aneurysm remnant from the MRA volume. Since manual segmentation of volumetric images is a labour-intensive and error-prone process, development of an automatic volumetric segmentation method is required. Segmentation of small structures such as IA, that may largely vary in size, shape, and location is considered extremely difficult. Similar intensity distribution of IAs and surrounding blood vessels makes it more challenging and susceptible to false positive. In this paper we propose a novel 3D CNN architecture called Dual-Attention Atrous Net (DAtt-ANet), which can efficiently segment IAR volumes from MRA images by reconciling features at different scales using the proposed Parallel Atrous Unit (PAU) along with the use of self-attention mechanism for extracting fine-grained features and intra-class correlation. The proposed DAtt-ANet model is trained and evaluated on a clinical MRA image dataset of IAR consisting of 46 subjects. We compared the proposed DAtt-ANet with five state-of-the-art CNN models based on their segmentation performance. The proposed DAtt-ANet outperformed all other methods and was able to achieve a five-fold cross-validation DICE score of 0.73 +/- 0.06.

  • 86.
    Banerjee, Subhashis
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Toumpanakis, Dimitrios
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Dhara, Ashis Kumar
    Natl Inst Technol Durgapur, Dept Elect Engn, Durgapur, India..
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction.
    Topology-Aware Learning for Volumetric Cerebrovascular Segmentation2022In: 2022 IEEE International Symposium on Biomedical Imaging (IEEE ISBI 2022), IEEE, 2022, p. 1-4Conference paper (Refereed)
    Abstract [en]

    This paper presents a topology-aware learning strategy for volumetric segmentation of intracranial cerebrovascular structures. We propose a multi-task deep CNN along with a topology-aware loss function for this purpose. Along with the main task (i.e. segmentation), we train the model to learn two related auxiliary tasks viz. learning the distance transform for the voxels on the surface of the vascular tree and learning the vessel centerline. This provides additional regularization and allows the encoder to learn higher-level intermediate representations to boost the performance of the main task. We compare the proposed method with six state-of-the-art deep learning-based 3D vessel segmentation methods, by using a public Time-Of-Flight Magnetic Resonance Angiography (TOF-MRA) dataset. Experimental results demonstrate that the proposed method has the best performance in this particular context.

  • 87.
    Banerjee, Subhashis
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division Vi3.
    Toumpanakis, Dimitrios
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Dhara, Ashis
    Department of Electrical Engineering, National Institute of Technology Durgapur, India.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division Vi3.
    Deep Curriculum Learning for Follow-up MRI Registration in Glioblastoma2023In: Medical Imaging 2023: Image Processing, SPIE -Society of Photo-Optical Instrumentation Engineers , 2023, Vol. 12464, article id 124643IConference paper (Refereed)
    Abstract [en]

    This paper presents a weakly supervised deep convolutional neural network-based approach to perform voxel-level3D registration between subsequent follow-up MRI scans of the same patient. To handle the large deformation inthe surrounding brain tissues due to the tumor’s mass effect we proposed curriculum learning-based training forthe network. Weak supervision helps the network to concentrate more focus on the tumor region and resectioncavity through a saliency detection network. Qualitative and quantitative experimental results show the proposedregistration network outperformed two popular state-of-the-art methods.

  • 88.
    Bannbers, Elin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Gingnell, Malin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Engman, Jonas
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Morell, Arvid
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Sylvén, Sara
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Skalkidou, Alkistis
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Kask, Kristiina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Wikström, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Radiology, Oncology and Radiation Science.
    Sundström-Poromaa, Inger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Prefrontal activity during response inhibition decreases over time in postpartum womenManuscript (preprint) (Other academic)
  • 89.
    Barnaure, I.
    et al.
    Univ Hosp Geneva, Div Neuroradiol, Geneva, Switzerland.
    Montandon, M-L.
    Univ Hosp Geneva, Dept Mental Hlth & Psychiat, Geneva, Switzerland.
    Rodriguez, C.
    Univ Hosp Geneva, Dept Mental Hlth & Psychiat, Geneva, Switzerland.
    Herrmann, F.
    Univ Hosp Geneva, Dept Internal Med, Geneva, Switzerland; Univ Hosp Geneva, Dept Rehabil, Geneva, Switzerland; Univ Hosp Geneva, Dept Geriatr, Geneva, Switzerland.
    Lövblad, K. O.
    Univ Hosp Geneva, Div Neuroradiol, Geneva, Switzerland.
    Giannakopoulos, P.
    Univ Hosp Geneva, Dept Mental Hlth & Psychiat, Geneva, Switzerland.
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Univ Hosp Freiburg, Dept Neuroradiol, Freiburg, Germany; Univ Geneva, Fac Med, Geneva, Switzerland.
    Clinicoradiologic Correlations of Cerebral Microbleeds in Advanced Age2017In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 38, p. 39-45Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND PURPOSE: The presence of cerebral microbleeds has been associated with dementia and cognitive decline, although studies report conflicting results. Our aim was to determine the potential role of the presence and location of cerebral microbleeds in early stages of cognitive decline.

    MATERIALS AND METHODS: Baseline 3T MR imaging examinations including SWI sequences of 328 cognitively intact community-dwelling controls and 72 subjects with mild cognitive impairment were analyzed with respect to the presence and distribution of cerebral microbleeds. A neuropsychological follow-up of controls was performed at 18 months post inclusion and identified cases with subtle cognitive deficits were referred to as controls with a deteriorating condition. Group differences in radiologic parameters were studied by using nonparametric tests, 1-way analysis of variance, and Spearman correlation coefficients.

    RESULTS: Cerebral microbleed prevalence was similar in subjects with mild cognitive impairment and controls with stable and cognitively deteriorating conditions (25%-31.9%). In all diagnostic groups, lobar cerebral microbleeds were more common. They occurred in 20.1% of all cases compared with 6.5% of cases with deep cerebral microbleeds. None of the investigated variables (age, sex, microbleed number, location and depth, baseline Mini-Mental State Examination score, and the Fazekas score) were significantly associated with cognitive deterioration with the exception of education of >12 years showing a slight but significant protective effect (OR, 0.44; 95% CI, 0.22-0.92; P = .028). The Mini-Mental State Examination and the Buschke total score were correlated with neither the total number nor lobar-versus-deep location of cerebral microbleeds.

    CONCLUSIONS: Cerebral microbleed presence, location, and severity are not related to the early stages of cognitive decline in advanced age.

  • 90.
    Baron, Tomasz
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Disciplinary Domain of Medicine and Pharmacy, research centers etc., Uppsala Clinical Research Center (UCR). Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Bergsten, Johannes
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Albåge, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Thoracic Surgery.
    Lundin, Lennart
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Öberg, Kjell
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrine Tumor Biology.
    Flachskampf, Frank A.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Cardiac Imaging in Carcinoid Heart Disease2021In: JACC Cardiovascular Imaging, ISSN 1936-878X, E-ISSN 1876-7591, Vol. 14, no 11, p. 2240-2253Article in journal (Refereed)
    Abstract [en]

    Carcinoid disease is caused by neuroendocrine tumors, most often located in the gut, and leads in approximately 20% of cases to specific, severe heart disease, most prominently affecting right-sided valves. If cardiac disease occurs, it determines the patient's prognosis more than local growth of the tumor. Surgical treatment of carcinoid-induced valve disease has been found to improve survival in observational studies. Cardiac imaging is crucial for both diagnosis and management of carcinoid heart disease; in the past, imaging was accomplished largely by echocardiography, but more recently, imaging for carcinoid heart disease has increasingly become multimodal and warrants awareness of the particular diagnostic challenges of this disease. This paper reviews the pathophysiology and manifestations of carcinoid heart disease in light of the different imaging modalities.

  • 91.
    Baron, Tomasz
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Disciplinary Domain of Medicine and Pharmacy, research centers etc., Uppsala Clinical Research Center (UCR). Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Uppsala University Hospital , 751 85 Uppsala , Sweden;Uppsala Clinical Research , 751 85 Uppsala , Sweden.
    Gerovasileiou, Spyridon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University Hospital , 751 85 Uppsala , Sweden;VO Medicin, Lasarettet i Enköping , all 785 81 Uppsala , Sweden.
    Flachskampf, Frank
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Disciplinary Domain of Medicine and Pharmacy, research centers etc., Uppsala Clinical Research Center (UCR). Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    The role of imaging in the selection of patients for HFpEF therapy2023In: European Heart Journal Cardiovascular Imaging, ISSN 2047-2404, E-ISSN 2047-2412, Vol. 24, no 10, p. 1343-1351Article in journal (Refereed)
    Abstract [en]

    Heart failure with preserved ejection fraction (HFpEF) traditionally has been characterized as a form of heart failure without therapeutic options, in particular with a lack of response to the established therapies of heart failure with reduced ejection fraction (HFrEF). However, this is no longer true. Besides physical exercise, risk factor modification, aldosterone blocking agents, and sodium-glucose cotransporter 2 inhibitors, specific therapies are emerging for specific HFpEF etiologies, such as hypertrophic cardiomyopathy or cardiac amyloidosis. This development justifies increased efforts to arrive at specific diagnoses within the umbrella of HFpEF. Cardiac imaging plays by far the largest role in this effort and is discussed in the following review.

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  • 92.
    Baron, Tomasz
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Örndahl, Lovisa Holm
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Kero, Tanja
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Sörensen, Jens
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Bjerner, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Hedin, Eva-Maria
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology-Arrhythmia. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology.
    Ståhle, Elisabeth
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Thoracic Surgery.
    Flachskampf, Frank A.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Comparison of left ventricular volumes and regurgitant volumes by echocardiography and magnetic resonance in patients with severe degenerative mitral regurgitation2016In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 37, p. 1239-1239Article in journal (Refereed)
  • 93.
    Batista Borges, João
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory. Univ Sao Paulo, Hosp Clin, Pulm Div Heart Inst InCor, Sao Paulo, Brazil..
    Hansen, Tomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Hedenstierna, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Physiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    The "normal" ventilated airspaces suffer the most damaging effects of mechanical ventilation2017In: Intensive Care Medicine, ISSN 0342-4642, E-ISSN 1432-1238, Vol. 43, no 7, p. 1057-1058Article in journal (Other academic)
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  • 94. Baudin, E.
    et al.
    Caplin, M.
    Garcia-Carbonero, R.
    Fazio, N.
    Ferolla, P.
    Filosso, P. L.
    Frilling, A.
    de Herder, W. W.
    Hörsch, D.
    Knigge, U.
    Korse, C. M.
    Lim, E.
    Lombard-Bohas, C.
    Pavel, M.
    Scoazec, J. Y.
    Sundin, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Berruti, A.
    Lung and thymic carcinoids: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up2021In: Annals of Oncology, ISSN 0923-7534, E-ISSN 1569-8041, Vol. 32, no 4, p. 439-451Article in journal (Refereed)
  • 95.
    Baudin, Eric
    et al.
    Inst Gustave Roussy, Oncol Endocrinienne & Med Nucl, Villejuif, France.
    Hayes, Aimee R.
    Royal Free Hosp, Neuroendocrine Tumour Unit, London, England.
    Scoazec, Jean-Yves
    Univ Lyon, Dept Pathol, Lyon, France.
    Filosso, Pier Luigi
    Univ Torino, Dept Thorac Surg, Turin, Italy.
    Lim, Eric
    Royal Brompton Hosp, Dept Thorac Surg, London, England.
    Kaltsas, Gregory
    Natl Univ Athens, Div Endocrinol, Dept Pathophysiol, Athens, Greece.
    Frilling, Andrea
    Imperial Coll London, Dept Surg & Canc, London, England.
    Chen, Jie
    Sun Yat Sen Univ, Affiliated Hosp 1, Dept Gastroenterol, Guangzhou, Guangdong, Peoples R China.
    Kos-Kudła, Beata
    Slaska Akad Med, Klin Endokrynol, Zabrze, Poland.
    Gorbunova, Vera
    Russian Acad Med Sci, FSBI NN Blokhin Russian Canc Res Ctr, Moscow, Russia.
    Wiedenmann, Bertram
    Charite Univ Med Berlin, Campus Charite Mitte, Dept Gastroenterol & Hepatol, Berlin, Germany; Charite Univ Med Berlin, Campus Virchow Klinikum, Berlin, Germany.
    Nieveen van Dijkum, Els
    Acad Med Ctr, Dept Surg, Amsterdam, Netherlands.
    Ćwikła, Jaroslaw B
    Univ Warmia & Mazury, Fac Med Sci, Dept Radiol, Olsztyn, Poland.
    Falkerby, Jenny
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrin Oncology.
    Valle, Juan W.
    Univ Manchester, Inst Canc Sci, Christie NHS Fdn Trust, Dept Med Oncol, Manchester, Lancs, England.
    Kulke, Matthew H
    Harvard Med Sch, Dana Farber Canc Inst, Dept Med Oncol, Boston, MA USA.
    Caplin, Martyn E
    Royal Free Hosp, Neuroendocrine Tumour Unit, London, England.
    Sundin, Anders (Contributor)
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Tiensuu Janson, Eva (Contributor)
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrin Oncology.
    Welin, Staffan (Contributor)
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Endocrin Oncology.
    Unmet Medical Needs in Pulmonary Neuroendocrine (Carcinoid) Neoplasms2019In: Neuroendocrinology, ISSN 0028-3835, E-ISSN 1423-0194, Vol. 108, no 1, p. 7-17Article in journal (Refereed)
    Abstract [en]

    Pulmonary carcinoids (PCs) display the common features of all well-differentiated neuroendocrine neoplasms (NEN) and are classified as low- and intermediate-grade malignant tumours (i.e., typical and atypical carcinoid, respectively). There is a paucity of randomised studies dedicated to advanced PCs and management principles are drawn from the larger gastroenteropancreatic NEN experience. There is growing evidence that NEN anatomic subgroups have different biology and different responses to treatment and, therefore, should be investigated as separate entities in clinical trials. In this review, we discuss the existing evidence and limitations of tumour classification, diagnostics and staging, prognostication, and treatment in the setting of PC, with focus on unmet medical needs and directions for the future.

  • 96. Beckmann, Katrin M.
    et al.
    Wang-Leandro, Adriano
    Dennler, Matthias
    Carrera, Ines
    Richter, Henning
    Bektas, Rima N.
    Steiner, Aline
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Faculty of Medicine of the University of Geneva, Geneva, Switzerland.
    Resting state networks of the canine brain under sevoflurane anaesthesia2020In: PLOS ONE, E-ISSN 1932-6203, Vol. 15, no 4, article id e0231955Article in journal (Refereed)
    Abstract [en]

    Resting-state functional Magnetic Resonance Imaging (rs-fMRI) has become an established technique in humans and reliably determines several resting state networks (RSNs) simultaneously. Limited data exist about RSN in dogs. The aim of this study was to investigate the RSNs in 10 healthy beagle dogs using a 3 tesla MRI scanner and subsequently perform group-level independent component analysis (ICA) to identify functionally connected brain networks. Rs-fMRI sequences were performed under steady state sevoflurane inhalation anaesthesia. Anaesthetic depth was titrated to the minimum level needed for immobilisation and mechanical ventilation of the patient. This required a sevoflurane MAC between 0.8 to 1.2. Group-level ICA dimensionality of 20 components revealed distributed sensory, motor and higher-order networks in the dogs' brain. We identified in total 7 RSNs (default mode, primary and higher order visual, auditory, two putative motor-somatosensory and one putative somatosensory), which are common to other mammals including humans. Identified RSN are remarkably similar to those identified in awake dogs. This study proves the feasibility of rs-fMRI in anesthetized dogs and describes several RSNs, which may set the basis for investigating pathophysiological characteristics of various canine brain diseases.

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  • 97.
    Beckmann, Katrin M.
    et al.
    Univ Zurich, Vetsuisse Fac Zurich, Dept Small Anim, Sect Neurol, Zurich, Switzerland..
    Wang-Leandro, Adriano
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland..
    Richter, Henning
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland.;Univ Hosp Bonn, Clin Neuroradiol, Bonn, Germany..
    Bektas, Rima N.
    Univ Zurich, Vetsuisse Fac, Dept Diagnost & Clin Serv, Sect Anaesthesiol, Zurich, Switzerland..
    Steffen, Frank
    Univ Zurich, Vetsuisse Fac Zurich, Dept Small Anim, Sect Neurol, Zurich, Switzerland..
    Dennler, Matthias
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland..
    Carrera, Ines
    Willows Vet Ctr & Referral Serv, Highlands Rd, Shirley, England..
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Univ Geneva, Fac Med, Geneva, Switzerland..
    Increased resting state connectivity in the anterior default mode network of idiopathic epileptic dogs2021In: Scientific Reports, E-ISSN 2045-2322, Vol. 11, no 1, article id 23854Article in journal (Refereed)
    Abstract [en]

    Epilepsy is one of the most common chronic, neurological diseases in humans and dogs and considered to be a network disease. In human epilepsy altered functional connectivity in different large-scale networks have been identified with functional resting state magnetic resonance imaging. Since large-scale resting state networks have been consistently identified in anesthetised dogs' application of this technique became promising in canine epilepsy research. The aim of the present study was to investigate differences in large-scale resting state networks in epileptic dogs compared to healthy controls. Our hypothesis was, that large-scale networks differ between epileptic dogs and healthy control dogs. A group of 17 dogs (Border Collies and Greater Swiss Mountain Dogs) with idiopathic epilepsy was compared to 20 healthy control dogs under a standardized sevoflurane anaesthesia protocol. Group level independent component analysis with dimensionality of 20 components, dual regression and two-sample t test were performed and revealed significantly increased functional connectivity in the anterior default mode network of idiopathic epileptic dogs compared to healthy control dogs (p = 0.00060). This group level differences between epileptic dogs and healthy control dogs identified using a rather simple data driven approach could serve as a starting point for more advanced resting state network analysis in epileptic dogs.

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  • 98.
    Beckmann, Katrin M.
    et al.
    Univ Zurich, Vetsuisse Fac Zurich, Dept Small Anim, Sect Neurol, Zurich, Switzerland.;Univ Bern, Grad Sch Cellular & Biomed Sci, Bern, Switzerland..
    Wang-Leandro, Adriano
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland.;Univ Vet Med Hannover, Dept Small Anim Med & Surg, Hannover, Germany..
    Steffen, Frank
    Univ Zurich, Vetsuisse Fac Zurich, Dept Small Anim, Sect Neurol, Zurich, Switzerland..
    Richter, Henning
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland..
    Dennler, Matthias
    Univ Zurich, Vetsuisse Fac Zurich, Dept Diagnost & Clin Serv, Clin Diagnost Imaging, Zurich, Switzerland..
    Bektas, Rima
    Univ Zurich, Vetsuisse Fac, Dept Clin Diagnost & Serv, Sect Anaesthesiol, Zurich, Switzerland..
    Carrera, Ines
    Vet Oracle Teleradiol, Norfolk, England..
    Haller, Sven
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Univ Geneva, Fac Med, Geneva, Switzerland..
    Diffusion tensor-based analysis of white matter in dogs with idiopathic epilepsy2023In: Frontiers in Veterinary Science, E-ISSN 2297-1769, Vol. 10, article id 1325521Article in journal (Refereed)
    Abstract [en]

    Introduction: The understanding of epileptic seizure pathogenesis has evolved over time, and it is now generally accepted that not only are cortical and subcortical areas involved but also the connection of these regions in the white matter (WM). Recent human neuroimaging studies confirmed the involvement of the WM in several epilepsy syndromes. Neuroimaging studies investigating WM integrity with diffusion tensor imaging (DTI) in canine idiopathic epilepsy are lacking. This study aimed to test the hypothesis that WM diffusion changes can be found in dogs affected by idiopathic epilepsy.

    Method: Twenty-six dogs with idiopathic epilepsy (15 Border Collies and 11 Greater Swiss Mountain dogs) and 24 healthy controls (11 Beagle dogs, 5 Border Collies, and 8 Greater Swiss Mountain dogs) were prospectively enrolled. Most dogs with idiopathic epilepsy (17/26) were enrolled within 3 months after seizure onset. Diffusion tensor imaging of the brain with 32 diffusion directions (low b value = 0 s/mm2; maximal b value = 800 s/mm2) was performed in a 3 Tesla scanner. Tract-based spatial statistics (TBSS), a voxel-based approach, was used to investigate changes in fractional anisotropy (FA) and mean diffusivity (MD) in the idiopathic epilepsy group compared to the healthy control group. Additionally, FA and MD were investigated in the region of corpus callosum and cingulate white matter in both groups.

    Results: We observed subtle changes in WM DTI between the idiopathic epilepsy group and the healthy control group limited to cingulate WM, with a significantly lower FA in the idiopathic epilepsy group compared to the healthy control group in the region of interest (ROI) approach (p = 0.027). No significant changes were found between the idiopathic epilepsy group and the healthy control group in the TBSS analysis and in the corpus callosum in the ROI approach.

    Conclusion: This study supports the cingulate area as a target structure in canine epilepsy. The subtle changes only might be explained by the short duration of epilepsy, small sample sizes, and the higher variability in canine brain anatomy. Furthermore, all included dogs showed generalized tonic-clonic seizures, possibly affected by generalized epilepsy syndrome, which are also associated with less pronounced DTI changes in humans than focal epilepsy syndromes.

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  • 99.
    Bencze, Janos
    et al.
    Univ Debrecen, Div Radiol & Imaging Sci, Dept Med Imaging, Fac Med, H-4032 Debrecen, Hungary.;Univ Debrecen, Dept Neurol, ELKH DE Cerebrovasc & Neurodegenerat Res Grp, H-4032 Debrecen, Hungary..
    Szarka, Mate
    Univ Debrecen, Fac Med, Res Ctr Mol Med, Horvath Csaba Lab Bioseparat Sci, H-4032 Debrecen, Hungary.;Vitrolink Kft, H-4033 Debrecen, Hungary.;Inst Nucl Res, H-4026 Debrecen, Hungary..
    Koti, Balazs
    Vitrolink Kft, H-4033 Debrecen, Hungary..
    Seo, Woosung
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
    Hortobagyi, Tibor G. G.
    Univ Szeged, Inst Pathol, Albert Szent Gyorgyi Med Sch, H-6725 Szeged, Hungary..
    Bencs, Viktor
    Univ Debrecen, Dept Neurol, Fac Med, H-4032 Debrecen, Hungary..
    Modis, Laszlo V.
    Univ Debrecen, Dept Behav Sci, Fac Med, H-4032 Debrecen, Hungary..
    Hortobagyi, Tibor
    Univ Debrecen, Dept Neurol, ELKH DE Cerebrovasc & Neurodegenerat Res Grp, H-4032 Debrecen, Hungary.;Univ Szeged, Inst Pathol, Albert Szent Gyorgyi Med Sch, H-6725 Szeged, Hungary.;Kings Coll London, Inst Psychiat Psychol & Neurosci, Dept Old Age Psychiat, London SE5 8AF, England.;Stavanger Univ Hosp, Ctr Age Related Med, SESAM, N-4011 Stavanger, Norway..
    Comparison of Semi-Quantitative Scoring and Artificial Intelligence Aided Digital Image Analysis of Chromogenic Immunohistochemistry2022In: Biomolecules, E-ISSN 2218-273X, Vol. 12Article in journal (Refereed)
    Abstract [en]

    Semi-quantitative scoring is a method that is widely used to estimate the quantity of proteins on chromogen-labelled immunohistochemical (IHC) tissue sections. However, it suffers from several disadvantages, including its lack of objectivity and the fact that it is a time-consuming process. Our aim was to test a recently established artificial intelligence (AI)-aided digital image analysis platform, Pathronus, and to compare it to conventional scoring by five observers on chromogenic IHC-stained slides belonging to three experimental groups. Because Pathronus operates on grayscale 0-255 values, we transformed the data to a seven-point scale for use by pathologists and scientists. The accuracy of these methods was evaluated by comparing statistical significance among groups with quantitative fluorescent IHC reference data on subsequent tissue sections. The pairwise inter-rater reliability of the scoring and converted Pathronus data varied from poor to moderate with Cohen's kappa, and overall agreement was poor within every experimental group using Fleiss' kappa. Only the original and converted that were obtained from Pathronus original were able to reproduce the statistical significance among the groups that were determined by the reference method. In this study, we present an AI-aided software that can identify cells of interest, differentiate among organelles, protein specific chromogenic labelling, and nuclear counterstaining after an initial training period, providing a feasible and more accurate alternative to semi-quantitative scoring.

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  • 100.
    Bengtsson Bernander, Karl
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala Univ, Ctr Image Anal, Uppsala, Sweden..
    Lindblad, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala Univ, Ctr Image Anal, Uppsala, Sweden..
    Strand, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computerized Image Analysis and Human-Computer Interaction. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology. Uppsala Univ, Ctr Image Anal, Uppsala, Sweden..
    Nystrom, Ingela
    Uppsala Univ, Ctr Image Anal, Uppsala, Sweden..
    Rotation-Equivariant Semantic Instance Segmentation on Biomedical Images2022In: MEDICAL IMAGE UNDERSTANDING AND ANALYSIS, MIUA 2022 / [ed] Yang, G Aviles-Rivero, A Roberts, M Schonlieb, CB, SPRINGER INTERNATIONAL PUBLISHING AG Springer Nature, 2022, Vol. 13413, p. 283-297Conference paper (Refereed)
    Abstract [en]

    Advances in image segmentation techniques, brought by convolutional neural network (CNN) architectures like U-Net, show promise for tasks such as automated cancer screening. Recently, these methods have been extended to detect different instances of the same class, which could be used to, for example, characterize individual cells in whole-slide images. Still, the amount of data needed and the number of parameters in the network are substantial. To alleviate these problems, we modify a method of semantic instance segmentation to also enforce equivariance to the p4 symmetry group of 90-degree rotations and translations. We perform four experiments on a synthetic dataset of scattered sticks and a subset of the Kaggle 2018 Data Science Bowl, the BBBC038 dataset, consisting of segmented nuclei images. Results indicate that the rotation-equivariant architecture yields similar accuracy as a baseline architecture. Furthermore, we observe that the rotation-equivariant architecture converges faster than the baseline. This is a promising step towards reducing the training time during development of methods based on deep learning.

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