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  • 1.
    Abdulhusen, Maria
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Binokulärseende hos elitidrottare: En studie om djupseende, ackommodationsfacilitet och vergensfacilitet2011Självständigt arbete på grundnivå (kandidatexamen), 15 poäng / 22,5 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syfte: Syftet med denna studie var att ta reda på om elitidrottare som spelar en bollsport har bättre djupseende, bättre förmåga att kunna ändra fokus mellan olika avstånd och mer uthålliga ögonmuskler än personer som inte spelar någon bollsport alls.

    Metod: Mätningarna utfördes på femton innebandyspelare som spelar på elitnivå och femton personer som inte spelar någon bollsport. Medelåldern var 22 år i båda grupperna. Först fick varje försöksperson svara på en enkät, sedan mättes visus upp monokulärt och binokulärt på 3 m med en logMAR visustavla. Efter det mättes djupseendet med Randot stereotest på 40 cm och sedan mättes försökspersonens förmåga att kunna ändra fokus mellan olika avstånd. Detta gjordes på 40 cm med en flipper med styrkorna ±2,00D. Sista mätningen var att få ett mått på hur uthålliga försökspersonens ögonmuskler var, detta gjordes på 40 cm med en flipper av styrkorna 3Δ Bas In/ 12Δ Bas Ut.

    Resultat: Medelvärdet på djupseendet i respektive grupp visade ingen statistisk signifikant skillnad mellan de båda grupperna (p=0,70). Det fanns en signifikant skillnad på medelvärdet mellan de båda grupperna när det gäller förmågan att kunna ändra fokus mellan olika avstånd (p=0,02). Medelvärdet på uthålligheten av ögonmusklerna visade ingen signifikant skillnad mellan de båda grupperna (p=0,08).

    Slutsats: Studien visade att innebandyspelare på elitnivå har bättre förmåga att ändra fokus mellan olika avstånd. Studien visade även att innebandypelare på elitnivå inte har mer uthålliga ögonmuskler eller bättre djupseende än de som inte spelar någon bollsport alls.

  • 2.
    Ahlm, Clas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Infektionssjukdomar.
    Lindén, Christina
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Linderholm, M
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Infektionssjukdomar.
    Alexeyev, O A
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Virologi.
    Billheden, J
    Elgh, Fredrik
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Virologi.
    Fagerlund, M
    Zetterlund, B
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurofysiologi.
    Settergren, B
    Central nervous system and ophthalmic involvement in nephropathia epidemica (European type of haemorrhagic fever with renal syndrome)1998Ingår i: Journal of Infection, ISSN 0163-4453, E-ISSN 1532-2742, Vol. 36, nr 2, s. 149-155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Central nervous system (CNS) - related symptoms occur in haemorrhagic fever with renal syndrome (HFRS). To study the CNS and ophthalmic involvement in nephropathia epidemica (NE), the European type of HFRS, we included 26 patients in a prospective study. Most common CNS-related symptoms were headache (96%), insomnia (83%), vertigo (79%), nausea (79%), and vomiting (71%). Ophthalmic symptoms were reported by 82% of patients; 41% had photophobia and 50% had impaired vision. A transient loss of vision was recorded in one patient, who also had a generalized seizure. Minor white matter lesions were found in about half of the patients investigated with brain magnetic resonance imaging (MRI). Electroencephalography (EEG) showed severe alterations in only one patient, and slight and reversible patterns in another two patients. Neopterin, interleukin-6 and interferon-gamma levels in the cerebrospinal fluid (CSF) were elevated, which may indicate immune activation. However, we found no evidence of intrathecal NE virus replication. We conclude that CNS-related symptoms are common in NE, and transient ophthalmic involvement can be demonstrated in about half of the patients.

  • 3.
    Ahmadi, Mahboobah
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Anatomi. Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Liu, Jing-Xia
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Anatomi.
    Brännström, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk biovetenskap, Patologi.
    Andersen, Peter M
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Stål, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Anatomi.
    Pedrosa-Domellöf, Fatima
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Human extraocular muscles in ALS2010Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 51, nr 7, s. 3494-3501Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE. To investigate the general morphology, fiber type content, and myosin heavy chain (MyHC) composition of extraocular muscles (EOMs) from postmortem donors with amyotrophic lateral sclerosis (ALS) and to evaluate whether EOMs are affected or truly spared in this disease. METHODS. EOM and limb muscle samples obtained at autopsy from ALS donors and EOM samples from four control donors were processed for immunohistochemistry with monoclonal antibodies against distinct MyHC isoforms and analyzed by SDS-PAGE. In addition, hematoxylin and eosin staining and nicotinamide tetrazolium reductase (NADH-TR) activity were studied. RESULTS. Wide heterogeneity was observed in the appearance of the different EOMs from each single donor and between donors, irrespective of ALS type or onset. Pathologic morphologic findings in ALS EOMs included presence of atrophic and hypertrophic fibers, either clustered in groups or scattered; increased amounts of connective tissue; and areas of fatty replacement. The population of fibers stained with anti-MyHCslow tonic was smaller than that of MyHCIpositive fibers and was mostly located in the orbital layer in most of the ALS EOM samples, whereas an identical staining pattern for both fiber populations was observed in the control specimens. MyHCembryonic was notably absent from the ALS EOMs. CONCLUSIONS. The EOMs showed signs of involvement with altered fiber type composition, contractile protein content, and cellular architecture. However, when compared to the limb muscles, the EOMs were remarkably preserved. EOMs are a useful model for the study of the pathophysiology of ALS.

  • 4. Alahamami, Mastour A.
    et al.
    Elsner, Ann E.
    Baskaran, Karthikeyan
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    YoussefAgha, Ahmed H.
    Brahm, Shane
    Young, Stuart B.
    Litvin, Taras V.
    Ozawa, Glen Y.
    Cuadros, Jorge
    Muller, Matthew S.
    Investigation of Photoreceptors in Diabetic Macular Edema2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Abstract Purpose: To evaluate the photoreceptor integrity in diabetic patients with macular edema using spectral domain optical coherence tomography (SD-OCT) Methods: We compared macular thickness in diabetic patients with and without macular edema to determine the role of damage to the external limiting membrane (ELM) or photoreceptors. Diabetic patients were selected from the screening study of > 2000 minority patients seen at Eastmont Wellness Center, Oakland, CA. Patients underwent photoscreening with a Canon Cr-DGi nonmydriatic camera (Tokyo, Japan) and an iVue OCT (Optovue Inc, Fremont, CA). Retinal scans of 70 diabetic patients, age range 33-68 yr., were selected so that A) 50% of patients had clinical significant macular edema (CSME), as diagnosed by the presence of hard exudates within 1 disc diameter from the fovea in the color photos, B) the full range of central macular thicknesses in our population was included. And C) patients with CSME were the same age as those not diagnosed with CSME. We graded the retinal scans according to the external limiting membrane (ELM) integrity; 6 patients had damaged ELM and the remaining 64 had intact ELM. Similarly, we graded the retinal scans according to the photoreceptor integrity; 14 patients had damaged photoreceptors and the remaining 56 had intact photoreceptors Results: Average retinal thickness was 254 µm (±57.4) and 356 µm (±95.9) in patients with intact and damaged ELM, respectively; and was 240 µm (±30.0), and 363 µm (±90.0) in patients with intact and damaged photoreceptors, respectively. Retinal thickness means were significantly greater for patients with damaged compared with intact ELM ( P=0.031). Similarly, Retinal thickness means in patients with damaged photoreceptors were significantly greater compared to patients with intact photoreceptors ( P = 0.0001). We also observed that all 6 patients who have damaged ELM were diagnosed with CSME, but were not significantly older than the diabetic patients not diagnosed with CSME ( P = 0.393) Conclusions: ELM and photoreceptor layer damage are found more often when retinal thickness exceeds 355 µm. It is not known if this outer retinal damage is the result of the edema or whether there is more edema because the outer retinal blood brain barrier is failing

  • 5. Alahamami, Mastour A.
    et al.
    Elsner, Ann E.
    Muller, Matthew S.
    Baskaran, Karthikeyan
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Gast, Thomas J.
    Litvin, Taras V.
    Ozawa, Glen Y.
    Cuadros, Jorge
    Haggerty, Bryan P.
    Malinovsky, Victor E.
    Clark, Christopher A.
    Brahm, Shane
    Young, Stuart B.
    Comparison of cysts in red and green images for diabetic macular edema2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose: To improve the detection of macular cyst with photoscreening, we tested whether in a population of largely minority patients the red channel image from a color fundus camera visualizes cysts in diabetic macular edema better than the green channel image. In assessing diabetic retinas for clinically significant macular edema, the presence of cysts must be judged with respect to the central macula. Some grading programs use red free images, often derived from green channel images, to enhance visualization of retinal vessel damage or macular pigment, but some red and near infrared instruments have detected cysts better than short wavelength techniques. Methods: We evaluated macular cysts in 13 diabetic patients diagnosed with clinically significant macular edema, age range 33-68 years. Diabetic patients were selected from the screening study of >2000 underserved patients seen at Eastmont Wellness Center, Oakland, CA. Patients underwent photoscreening with a nonmydriatic color fundus camera (Canon Cr-DGi, Tokyo, Japan) and SD-OCT (iVue, Optovue Inc, Fremont, CA). The color fundus images for those patients were transformed into red and green channels to evaluate the appearance of macular cysts in red channel images and green channel images. The region of each cyst was compared SD-OCT scans (Adobe Photoshop CS5.1, San Jose, CA). Only cysts touching the central 1 mm around the fixation from the SD-OCT scans were sampled. Results: The average size of retinal cysts in red channel images, 124.57 µm (±106.96), was significantly greater than in green channel, 59.44 µm (±76.6), (p<0.006). Entire cysts could not be seen in 5 eyes in the green channel images. Conclusions: Our results indicate that the grading of cysts in the central macular might be improved by incorporating red channel images. There are a number of potential factors that could make cysts less visible in the green channel images, including poorer light penetration through to the deeper retina or macular pigment. Anterior segment issues impact more on green channel images. This population includes mostly minority patients who have dark fundi, and darker images.

  • 6.
    Alhamami, Mastour
    et al.
    Indiana University School of Optometry, USA.
    Elsner, Ann
    Indiana University School of Optometry, USA ; Aeon Imaging, USA.
    Malinovsky, Victor
    Indiana University School of Optometry, USA.
    Clark, Christopher
    Haggerty, Bryan
    Indiana University School of Optometry, USA.
    Ozawa, Glen
    University of California, USA.
    Cuadros, Jorge A
    University of California, USA ; EyePACS, USA.
    Baskaran, Karthikeyan
    Indiana University School of Optometry, USA.
    Gast, Thomas
    Indiana University School of Optometry, USA ; Aeon Imaging, USA.
    Litvin, Taras
    University of California, USA.
    Muller, Matthew
    Aeon Imaging, USA.
    Brahm, Shane
    Indiana University School of Optometry, USA.
    Young, Stuart
    Indiana University School of Optometry, USA.
    Miura, Masahiro
    Tokyo Medical University Ibaraki Medical Center, Japan.
    Comparison of Cysts in Red and Green Images for Diabetic Macular Edema2017Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 94, nr 2, s. 137-149Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To investigate whether cysts in diabetic macular edema are better visualized in the red channel of color fundus camera images, as compared with the green channel, because color fundus camera screening methods that emphasize short-wavelength light may miss cysts in patients with dark fundi or changes to outer blood retinal barrier.

    Methods: Fundus images for diabetic retinopathy photoscreening were acquired for a study with Aeon Imaging, EyePACS, University of California Berkeley, and Indiana University. There were 2047 underserved, adult diabetic patients, of whom over 90% self-identified as a racial/ethnic identify other than non-Hispanic white. Color fundus images at nominally 45 degrees were acquired with a Canon Cr-DGi non-mydriatic camera (Tokyo, Japan) then graded by an EyePACS certified grader. From the 148 patients graded to have clinically significant macular edema by the presence of hard exudates in the central 1500 [mu]m of the fovea, we evaluated macular cysts in 13 patients with cystoid macular edema. Age ranged from 33 to 68 years. Color fundus images were split into red, green, and blue channels with custom Matlab software (Mathworks, Natick, MA). The diameter of a cyst or confluent cysts was quantified in the red-channel and green-channel images separately.

    Results: Cyst identification gave complete agreement between red-channel images and the standard full-color images. This was not the case for green-channel images, which did not expose cysts visible with standard full-color images in five cases, who had dark fundi. Cysts appeared more numerous and covered a larger area in the red channel (733 +/- 604 [mu]m) than in the green channel (349 +/- 433 [mu]m, p < 0.006).

    Conclusions: Cysts may be underdetected with the present fundus camera methods, particularly when short-wavelength light is emphasized or in patients with dark fundi. Longer wavelength techniques may improve the detection of cysts and provide more information concerning the early stages of diabetic macular edema or the outer blood retinal barrier.

  • 7.
    Allen, Peter M.
    et al.
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    Radhakrishnan, Hema
    Vision Cooperative Research Centre, Australia ; University of Manchester, UK.
    Price, Holly
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    Rae, Sheila
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    Theagarayan, Baskar
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    Calver, Richard I.
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    Sailoganathan, Ananth
    National Institute of Ophthalmic Sciences, Malaysia.
    Latham, Keziah
    Anglia Ruskin University, UK.
    O'Leary, Daniel J.
    Anglia Ruskin University, UK ; Vision Cooperative Research Centre, Australia.
    A randomised clinical trial to assess the effect of a dual treatment on myopia progression: the Cambridge anti-myopia study2013Ingår i: Ophthalmic & physiological optics, ISSN 0275-5408, E-ISSN 1475-1313, Vol. 33, nr 3, s. 267-276Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To evaluate the effect of a dual treatment modality for myopia, by improving accommodative functions, on myopia progression.

    METHODS: A double blind randomised control trial was conducted on 96 subjects. The treatment modality for the trial employed custom designed contact lenses which control spherical aberration in an attempt to optimise static accommodation responses during near-work, and a vision-training programme to improve accommodation dynamics. Myopia progression was assessed over a 2 year period using cycloplegic autorefraction and biometry.

    RESULTS: The mean progression was found to be -0.33 Dioptres (D) over the 2 years of the study. There was no interaction between contact lens treatment and vision training treatment at 24 months (p = 0.72). There was no significant treatment effect of either Vision Training or Contact Lens Spherical Aberration control on myopia progression.

    CONCLUSIONS: This study is unable to demonstrate that the progression of myopia can be reduced over a 2 year period by either of the two treatments aimed at improving accommodative function. Neither treatment group (contact lens or vision training) progressed at a slower rate over the 2 years of the study than did the appropriate control group.

  • 8.
    Allen, Peter M.
    et al.
    Anglia Ruskin University, UK.
    Radhakrishnan, Hema
    University of Manchester, UK.
    Rae, Sheila
    Anglia Ruskin University, UK.
    Calver, Richard I.
    Anglia Ruskin University, UK.
    Theagarayan, Baskar
    Anglia Ruskin University, UK.
    Nelson, Paul
    Prism Training Consultancy, UK.
    Osuobeni, Ebi
    Anglia Ruskin University, UK.
    Sailoganathan, Ananth
    Anglia Ruskin University, UK.
    Price, Holly
    Anglia Ruskin University, UK.
    O'Leary, Daniel J.
    Anglia Ruskin University, UK.
    Aberration control and vision training as an effective means of improving accommodation in individuals with myopia.2009Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 50, nr 11, s. 5120-5129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To test the efficacy of a novel dual treatment for improving accommodative accuracy and dynamics in young persons with myopia.

    METHODS: Ninety-three young persons with myopia (mean spherical equivalent, -3.0 +/- 1.8 D; age 16.8 +/- 2.1 years; spherical aberration +0.06 +/- 0.04 microm) participated in the study. Custom-designed soft contact lenses were used to alter ocular SA to -0.10 microm to improve accommodative accuracy and reduce any lag of accommodation. A vision training regimen was performed for 18 minutes per day for up to 6 weeks to improve speed of dynamic accommodation. Control groups had contact lenses with no added SA and/or no exercises. To avoid any effects of natural levels of negative aberration on the results of the study, all participants who had negative SA were excluded.

    RESULTS: The treatment contact lenses produced a significant reduction in lag of accommodation (P < 0.05) at all proximal viewing distances measured. The vision training measurement and treatment resulted in a significant increase in distance facility rate for all groups compared with their own baselines (P < 0.05). Near facility rate improved in the vision training treatment group only compared with its baseline (P < 0.05). Both positive and negative response times for distant viewing were significantly shorter in all groups after training compared with their baseline values (P < 0.05). At near, the positive response times were decreased significantly (P < 0.05) in both groups, whereas the negative response times decreased significantly only in the vision training treatment group.

    CONCLUSIONS: After 3 months, the dual treatments (altering SA and vision training) used in the study were effective in modifying accommodation. The static accommodative response to targets at proximal distances was increased by the altered SA contact lenses and rates of dynamic accommodation improved with vision training.

  • 9.
    Alm, A.
    et al.
    Uppsala universitet, Medicinska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap. Uppsala universitet, Medicinska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap. Oftalmiatrik.
    Schoenfelder, J.
    McDermott, J.
    A 5-year, multicenter, open-label, safety study of adjunctive latanoprost therapy for glaucoma.2004Ingår i: Arch Ophthalmol, Vol. 122, s. 957-965Artikel i tidskrift (Refereegranskat)
  • 10.
    Alm, Albert
    et al.
    Ögonkliniken, Akademiska sjukhuset, Uppsala .
    Bengtsson, Boel
    Oftalmologi, SUS, Malmö.
    Calissendorff, Berit
    St Eriks ögonsjukhus, Stockholm.
    Eckerlund, Ingemar
    Swedish Council on Technology Assessment in Health Care, Stockholm.
    Heijl, Anders
    Department of Clinical Sciences, Ophthalmology in Malmö.
    Lindén, Christina
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Öppenvinkelglaukom (grön starr): diagnostik, uppföljning och behandling. En systematisk litteraturöversikt.2008Rapport (Övrigt vetenskapligt)
  • 11.
    Alm, Håkan
    Högskolan i Kalmar, Naturvetenskapliga institutionen.
    Är svenska optikerbutiker tillgängliga för rörelsehindrade människor?2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Legitimerade optiker står under Hälso- och sjukvårdslagen och har därmed samma skyldigheter som övrig hälso- och sjukvårdspersonal. En optiker ska således kunna ta emot och erbjuda sina tjänster till alla människor. Studiens syfte var att undersöka hur väl detta fungerar i praktiken. Detta gjordes genom att undersöka optikerbutiker och bedöma dess tillgänglighet för rullstolsburna människor. Undersökningsgruppen bestod av 20 optikerbutiker fördelade på en mindre respektive en större sydsvensk stad. En enkät konstruerades utifrån studiens syfte som butikerna fick svara på samt en checklista skapades innehållande följande bedömningsområden: dörrar, korridorer, gångar, dörröppnare, trösklar samt trappsteg. Resultatet visade på stora brister i tillgänglighet. Endast 20 % av butikerna klassades som tillgängliga och enkätsvaren visade att var femte optiker någon gång ej haft möjlighet att undersöka en patient på grund av dess funktionshinder. Studien visar att de svenska optikerbutikerna inte lever upp till Hälso- och sjukvårdslagens krav på ”vård på lika villkor för hela befolkningen”.

  • 12.
    Ambarki, Khalid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Hallberg, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jóhannesson, Gauti
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Lindén, Christina
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Zarrinkoob, Laleh
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Wåhlin, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Blood flow of ophthalmic artery in healthy individuals determined by phase-contrast magnetic resonance imaging2013Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 54, nr 4, s. 2738-2745Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: Recent development of magnetic resonance imaging (MRI) offers new possibilities to assess ocular blood flow. This prospective study evaluates the feasibility of phase-contrast MRI (PCMRI) to measure flow rate in the ophthalmic artery (OA) and establish reference values in healthy young (HY) and elderly (HE) subjects.

    METHODS: Fifty HY subjects (28 females, 21-30 years of age) and 44 HE (23 females, 64-80 years of age) were scanned on a 3-Tesla MR system. The PCMRI sequence had a spatial resolution of 0.35 mm per pixel, with the measurement plan placed perpendicularly to the OA. Mean flow rate (Qmean), resistive index (RI), and arterial volume pulsatility of OA (ΔVmax) were measured from the flow rate curve. Accuracy of PCMRI measures was investigated using a vessel-phantom mimicking the diameter and the flow rate range of the human OA.

    RESULTS: Flow rate could be assessed in 97% of the OAs. Phantom investigations showed good agreement between the reference and PCMRI measurements with an error of <7%. No statistical difference was found in Qmean between HY and HE individuals (HY: mean ± SD = 10.37 ± 4.45 mL/min; HE: 10.81 ± 5.15 mL/min, P = 0.655). The mean of ΔVmax (HY: 18.70 ± 7.24 μL; HE: 26.27 ± 12.59 μL, P < 0.001) and RI (HY: 0.62 ± 0.08; HE: 0.67 ± 0.1, P = 0.012) were significantly different between HY and HE.

    CONCLUSIONS: This study demonstrated that the flow rate of OA can be quantified using PCMRI. There was an age difference in the pulsatility parameters; however, the mean flow rate appeared independent of age. The primary difference in flow curves between HE and HY was in the relaxation phase of the systolic peak.

  • 13.
    Andersson, Linda
    Högskolan i Kalmar, Naturvetenskapliga institutionen.
    Hanteringsträning - tidsåtgång och trygghetskänsla för patienter vid isättning och urtagning av mjuka kontaktlinser2009Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 14.
    Andersson, Ulrika
    et al.
    Högskolan i Halmstad, Sektionen för hälsa och samhälle (HOS).
    Helin, Ann-Sofi
    Högskolan i Halmstad, Sektionen för hälsa och samhälle (HOS).
    Ögonsjuksköterskors upplevelser av att använda sin specifika omvårdnadskunskap vid telefonrådgivning2013Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Telefonrådgivning är en vanlig vårdform. I en alltmer medicinskt och tekniskt utvecklad ögonsjukvård efterfrågas ögonsjuksköterskornas omvårdnadskompetens av både patienter, anhöriga och kollegor inom andra delar av sjukvården. Syftet med studien var att undersöka ögonsjuksköterskors upplevelser av att använda sin specifika omvårdnadskunskap vid telefonrådgivning inom ögonsjukvård. Studien genomfördes med en kvalitativ metod och data samlades in genom semistrukturerade intervjuer. Materialet analyserades med kvalitativ innehållsanalys. Resultatet visade att ögonsjuksköterskorna upplevde arbetet som utvecklande och utmanande. De såg sig själva som en lots i vården med en stor rådgivande funktion relaterat till sin specifika kunskap. De beskrev också en del svårigheter med att triagera via telefon. De önskade bättre bedömningsunderlag men var dock trygga med sina bedömningar och någon rädsla för anmälningar till tillsynsmyndighet framkom inte. De uttryckte även ett behov av utbildning inom samtalsmetodik. Ögonsköterskorna saknade tid för kollegiala reflektioner för att utveckla sin professionella hållning i arbetet med telefonrådgivningen

  • 15. Anjos, Rita
    et al.
    Vieira, Luisa
    Costa, Livio
    Vicente, André
    Ophthalmology Department, Centro Hospitalar de Lisboa Central, Lisbon, Portugal; Serviço de Oftalmologia, Hospital de Santo António dos Capuchos, Lisbon, Portugal.
    Santos, Arnaldo
    Alves, Nuno
    Amado, Duarte
    Ferreira, Joana
    Cunha, João Paulo
    Macular Ganglion Cell Layer and Peripapillary Retinal Nerve Fibre Layer Thickness in Patients with Unilateral Posterior Cerebral Artery Ischaemic Lesion: An Optical Coherence Tomography Study2016Ingår i: Neuro-ophthalmology (Aeolus Press. 1980), ISSN 0165-8107, E-ISSN 1744-506X, Vol. 40, nr 1, s. 8-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this study is to evaluate the macular ganglion cell layer (GCL) and peripapillary retinal nerve fibre layer (RNFL) thickness in patients with unilateral posterior cerebral artery (PCA) ischaemic lesions using spectral-domain optical coherence tomography (SD-OCT). A prospective, case-control study of patients with unilateral PCA lesion was conducted in the neuro-ophthalmology clinic of Centro Hospitalar Lisboa Central. Macular and peripapillary SD-OCT scans were performed in both eyes of each patient. Twelve patients with PCA lesions (stroke group) and 12 healthy normal controls were included in this study. Peripapillary RNFL comparison between both eyes of the same subject in the stroke group found a thinning in the superior-temporal (p = 0.008) and inferior-temporal (p = 0.023) sectors of the ipsilateral eye and nasal sector (p = 0.003) of the contralateral eye. Macular GCL thickness comparison showed a reduction temporally in the ipsilateral eye (p = 0.004) and nasally in the contralateral eye (p = 0.002). Peripapillary RNFL thickness was significantly reduced in both eyes of patients with PCA compared with controls, affecting all sectors in the contralateral eye and predominantly temporal sectors in the ipsilateral eye. A statistically significant decrease in macular GCL thickness was found in both hemiretinas of both eyes of stroke patients when compared with controls (p < 0.05). This study shows that TRD may play a role in the physiopathology of lesions of the posterior visual pathway.

  • 16.
    Aronsson, Catrin
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Hur skiljer sig ackommodationsamplituden mellan Nicaragua och Sverige?2011Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syfte: Syftet med denna undersökning var att mäta ackommodationsamplitud i Nicaragua och Sverige för att se om det är någon signifikant skillnad mellan länderna i åldersgrupperna mellan 8 år och 40 år. Värdena som togs fram jämfördes sedan med publicerad litteratur för att undersöka hur denna studies värde skiljer sig från dessa, samt vilken av de tidigare studierna som var mest lik denna studies framtagna värde på ackommodationsamplitud i förhållande till åldern.

    Metod: Mätningarna skedde på 113 personer i Nicaragua och 113 personer i Sverige. För att vara med i denna studie krävdes det att försökspersonerna översteg 8 år och understeg 40 år. Mätningarna genomfördes med push-up metoden med hjälp av en mätsticka med figuroptotyp i form av en fågel.

    Resultat: Av de mätningar som genomfördes blev genomsnittet av ackommodationsamplitud 10,3 D (strandard avvikelse ±9,7 D) i Nicaragua och 11,5 D (standard avvikelse ±6,5 D) i Sverige. Ingen signifikant skillnad finns mellan länderna, det vill säga land (Nicaragua eller Sverige) har ingen påverkan på ackommodations amplitud enligt denna studie. Signifikans finns dock mellan ålder och ackommodation, en bekräftelse på att ålder påverkar ackommodationen har således observerats.

    Slutsats: Någon signifikant skillnad i ackommodationsamplitud mellan Nicaragua och Sverige kunde enligt denna studie ej påvisas. I jämförelsen mellan avvikelserna från både Duane och Donders tabeller jämte denna studie kan det avläsas att tabellerna har underskattat mängd ackommodationsamplitud.

  • 17. Arthur, Edmund
    et al.
    Young, Stuart B.
    Baskaran, Karthikeyan
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Elsner, Ann E.
    Muller, Matthew S.
    Gast, Thomas J.
    Haggerty, Bryan P.
    Clark, Christopher A.
    Brahm, Shane
    Litvin, Taras V.
    Ozawa, Glen Y.
    Cuadros, Jorge
    Individual Retinal Layer Thickness in Diabetic Patients with Clinically Significant Macular Edema: A Gender Based Analysis2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose: To compare segmented retinal layer thicknesses between male and female diabetics with clinically significant macular edema (CSME). This study expands our earlier analysis of central macular thickness (CMT) measurements in diabetic males vs. females. Methods: Diabetic retinopathy screening of 2080 diabetics from Alameda County, CA, indicated 142 patients with CSME, as judged by EyePACS certified graders using color fundus images (Canon CR6-45NM). Of the 2080 diabetics, 1784 were imaged with SD-OCT (Optovue iVue). From the 142 patients, we selected 11 males with good fixation, CMT > 300 µm, and no other ocular complications, along with 11 females with the greatest values of CMT while controlling for age, HbA1c and diabetes duration. Manual segmentation of retinal layers using custom software (Mathworks Matlab) of the SD-OCT images of these subjects was done. We analyzed thicknesses for regions 1 deg - 2 deg for nasal and temporal retina in a B-scan centered on the fovea. A 2 X 2 ANOVA probed the differences in thickness for gender, meridian, and their interaction. We also analyzed the central 1 mm of the outer retinal layers, and performed t-tests. Results: Males had significantly thicker nerve fiber layer (NFL) (13.30 ± 2.85 µm) than females (10.13 ± 6.13 µm) and ganglion cell layer-inner plexiform layer (GCL-IPL) (62.54 ± 21.18 µm) than females (48.07 ± 25.91 µm), p < 0.05. There was no effect of meridian and no interaction (p > 0.05). All other layers except the retinal pigment epithelium (RPE) were thicker for males than females even though these were not significant (p > 0.05). There were no significant differences for the layers of the outer retina, which were highly variable and distorted by cysts. Conclusion: Outside the fovea, NFL and GCL-IPL thicknesses were significantly higher in males than females.

  • 18.
    Artzén, Ditte
    et al.
    S:t Erik Eye Hospital, Stockholm.
    Lundström, Mats
    EyeNet Sweden, Blekinge Hospital, Karlskrona.
    Behndig, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Stenevi, Ulf
    Sahlgrenska University Hospital, Mölndal, .
    Lydahl, Eva
    Lake Mälare Hospital, Eskilstuna.
    Montan, Per
    St. Erik Eye Hospital, Stockholm.
    Capsule complication during cataract surgery: Case-control study of preoperative and intraoperative risk factors: Swedish Capsule Rupture Study Group report 2.2009Ingår i: Journal of cataract and refractive surgery, ISSN 0886-3350, E-ISSN 1873-4502, ISSN ISSN 0886-3350, Vol. 35, nr 10, s. 1688-1693Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abstract

    PURPOSE: To identify preoperative and intraoperative factors associated with a capsule complication; that is, a capsule tear or a zonular dehiscence during cataract surgery. SETTING: Ten ophthalmic surgery departments in Sweden. METHODS: A retrospective review of files of patients with a capsule complication and control patients with no complication operated on in 2003 was performed. RESULTS: The review comprised 324 patients with a capsule complication and 331 control patients. In the logistic regression analyses, preoperative conditions associated with a capsule complication were previous trauma, white and brunescent/hard cataract, and phacodonesis. The intraoperative factors of loose zonules, the use of trypan blue, and miosis were all statistically significantly overrepresented in the capsule complication group. The same was true for eyes operated on by surgeons with the least experience. CONCLUSIONS: By preoperatively identifying cataract cases with the identified risk factors and allocating them to surgeons with the longest experience, the number of capsule complications could be kept low. Operating early in the course of the disease to prevent the cataract from becoming a poor surgical risk and improving training of junior surgeons should further reduce the frequency of capsule complications.

  • 19.
    Arvidsson, Emma
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Skiljer sig blinkfrekvensen vid läsning på olika medier?2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syfte: Syftet med den här studien var att undersöka om Spontaneous Eye Blink Rate (SEBR) skiljde sig åt vid läsning på utskrivet papper, surfplatta eller smartphone. Det jämfördes också huruvida fullständiga och ofullständiga blinkningar skiljde sig åt vid läsning på de olika medierna.

    Metod: Deltagarna (n=29) fick läsa tre olika texter på utskrivet papper, surfplatta och smartphone samtidigt som de filmades. I efterhand granskades samtliga videos två gånger för att räkna fullständiga blinkningar, ofullständiga blinkningar och totalt antal blinkningar (SEBR).

    Resultat: Den här studien visade att där finns en signifikant skillnad av totalt antal blinkningar vid läsning på utskrivet papper och surfplatta (p=0,03), där blinkningar/minut sjönk med 14,9% vid läsning på utskrivet papper, jämfört med surfplatta. För ofullständiga blinkningar fanns en statistiskt signifikant skillnad mellan utskrivet papper och surfplatta (p=0,02), där antalet ofullständiga blinkningar/minut ökade med 30,0% vid läsning på surfplatta, jämfört med utskrivet papper. Vid läsning på surfplatta och smartphone fanns en signifikant skillnad gällande ofullständiga blinkningar (p=0,01), där antalet ofullständiga blinkningar/minut ökade med 42% vid läsning på surfplattan, jämfört med smartphone. 

    Slutsats: Spontaneous Eye Blink Rate skiljer sig vid läsning på papper och surfplatta. Ofullständiga blinkningar är flest vid läsning på surfplatta. Inga signifikanta skillnader finns mellan utskrivet papper och smartphone.  

  • 20.
    Arvidsson, Marie-Louise
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Vilken läshastighet ger den svenska versionen av internationellt standardiserade läshastighetstexter?2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund - Att läsa en tidning är en självklarhet för många  idag. Det är en naturlig del av vardagen att tillgodogöra sig skriftlig information. Det här är inte en självklar sanning. Många med nedsatt syn behöver använda hjälpmedel som förstorande optik och starkare belysning m m för att klara den här vardagliga situationen. Hur mäts läsförmågan som den synskadade har? Det finns olika lästester för det här syftet.  Testerna som finns sedan tidigare består av enstaka meningar i olika storlekar. I det EU-baserade AMD-Read projektet togs det fram ett set med 10st  nya  längre läshastighetstexter. Eftersom de här nyare texterna (IReST) består av längre sammanhängande meningar i varje lässtycke så finns möjligheten att mäta den faktiska läshastigheten som den synskadade har.  Det går att jämföra resultat före och efter korrektion eller synträning. Texterna finns standardiserade på finska, franska, tyska, engelska, portugisiska och arabiska.

    Syfte - Syftet med denna studie är att utvärdera den svenska versionen av IReST texterna. Frågeställningen var om de tio svenska texterna gav ett jämförbart resultat i läshastighet.

    Metod – 25 friska normalseende personer 19-35 år deltog i studien. Deltagarna fick en och en läsa de 10 läshastighetstexterna högt under tidtagning och röstinspelning. Texterna lästes i slumpvis ordning.

    Resultat -  Två av de tio texterna tog signifikant längre tid att läsa mot de övriga åtta. När det gäller antal fellästa tecken/minut fanns det ingen signifikant skillnad mellan de tio texterna.

  • 21.
    Aström, Siv
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Lindén, Christina
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Incidence and prevalence of pseudoexfoliation and open-angle glaucoma in northern Sweden: I. Baseline report.2007Ingår i: Acta Ophthalmologica Scandinavica, ISSN 1395-3907, E-ISSN 1600-0420, Vol. 85, nr 8, s. 828-831Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To evaluate the prevalence of pseudoexfoliation (PEX) syndrome and open-angle glaucoma (OAG) among 66-year-old people in the municipality of Skellefteå in northern Sweden.

    METHODS: A population-based study comprising 339 individuals, representing 40% of the age group and 87% of those randomly selected. The examination included tonometry, dilated slit-lamp biomicroscopy, optic disc evaluation and a visual field analysis if glaucoma was suspected.

    RESULTS: The overall prevalence of PEX syndrome was 23%[95% confidence interval (CI): 20-26%], 29% (CI: 24-34%) in women and 15% (CI: 10-19%) in men (P < 0.01). The intraocular pressure (IOP) in PEX eyes was higher (17.3 mmHg, SD 4.5 mmHg) than in eyes without PEX [15.7 mmHg, SD 3.7 mmHg; P < 0.001]. IOP exceeded 22 mmHg in 17% (CI: 11-23%) of the PEX eyes and in 3.0% (CI: 1.9-4.1%) of the non-PEX eyes. Seven individuals (2.1%) had OAG. Six were associated with PEX, i.e. 7.7% of the PEX individuals.

    CONCLUSION: PEX syndrome is common in northern Sweden, affecting every fourth individual reaching the age of 66 years. The prevalence in women is twice that in men. Elevated IOP is roughly six times more frequent in eyes with PEX than in eyes without PEX syndrome. The prevalence of OAG is 2.1%.

  • 22.
    Aurell, Sandra
    et al.
    Vastmanland Cty Hosp, AT Ctr, S-72189 Vasteras, Sweden..
    Granstam, Elisabet
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, Centrum för klinisk forskning, Västerås. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Oftalmiatrik. Vastmanland Cty Hosp, Dept Ophthalmol, Vasteras, Sweden..
    Bacterial keratitis in a Swedish county hospital: management and clinical outcome2016Ingår i: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 94, nr 3, s. E248-E249Artikel i tidskrift (Refereegranskat)
  • 23.
    Austeng, Dordi
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Retinopathy of Prematurity in Infants Born Before 27 Weeks of Gestation: A National Population-based Study in Sweden During 2004-20072010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Background: Improved neonatal care has resulted in an increasing population of surviving infants. Neonatal morbidity in preterm infants is, however, high, and retinopathy of prematurity (ROP) is one of the major neonatal morbidities. Observations have suggested that ROP might have a different course in extremely preterm compared to more mature infants.

    Aims: To study the incidence, natural history and treatment of the disease, and the implications regarding screening recommendations for the population of extremely preterm infants.

    Methods: A national, population-based study of neonatal morbidity in infants born before 27 gestational weeks was performed in Sweden during 2004 to 2007. ROP screening started in the 5th postnatal week and continued until the retina was completely vascularized.

    Results: Of the 506 infants surviving until the first ROP examination, 73% developed ROP; 38% mild ROP and 35% severe ROP. Ninety-nine infants (20%) were treated. A log-linear relationship was found between severe ROP and gestational age (GA) at birth, and the risk of ROP was reduced by 50% for each week of increase in GA at birth (Paper I).

    Postmenstrual age (PMA) at onset of ROP was significantly related to GA at birth, as was the site of onset of ROP. ROP had a predilection to start in the nasal retina in the most immature infants. There were significant relations between PMA at onset of ROP and severity of ROP as well as between the site of onset of ROP and severe ROP (Paper III).

    The most immature infants had a higher risk of reaching treatment criteria for ROP, a higher risk of progression from ROP 3 to treatment criteria, and they reached these criteria at an earlier PMA than the less immature infants (Paper II).

    According to our results, the first examination can be postponed until a PMA of 31 weeks in infants born before 27 weeks of gestation, since onset of ROP 3 did not occur before this age, and criteria for treatment were not reached before 32 weeks. The majority of infants (75%) were treated during a limited period, i.e. before a PMA of 39 weeks (Paper IV).

  • 24.
    Austeng, Dordi
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Källen, Karin B. M.
    Lund University.
    Ewald, Uwe W.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kvinnors och barns hälsa.
    Wallin, Agneta
    St.Erik's Eye Hospital.
    Holmström, Gerd E.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Treatment for retinopathy of prematurity in infants born before 27 weeks of gestation in Sweden2010Ingår i: British Journal of Ophthalmology, ISSN 0007-1161, E-ISSN 1468-2079, Vol. 94, nr 9, s. 1136-1139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    AIMS: To study various aspects of treatment for retinopathy of prematurity (ROP) in a Swedish population of extremely preterm infants born before 27 weeks of gestation. METHODS: A national, prospective and population-based study was performed in Sweden from April 1, 2004 to March 31, 2007. The criteria for treatment of ROP accorded with the recommendations of the Early Treatment for Retinopathy of Prematurity Cooperative Group. RESULTS: Twenty percent of the infants (99/506) were treated for ROP. The likelihood of reaching treatment criteria nearly doubled for each week of reduction in gestational age (GA) at birth. The first treatment was performed at an earlier postmenstrual age in the most immature infants. One third of the infants had more than one session of laser treatment. CONCLUSIONS: A high percentage of these extremely preterm infants required treatment for ROP. The likelihood of reaching treatment criteria increased with a decline in GA at birth. Although only a few infants progressed to ROP Stages 4 and 5, our findings indicate a potential for improvement of the treatment routines, both regarding timing and number of laser spots at the first treatment.

  • 25.
    Austeng, Dordi
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Oftalmiatrik.
    Källen, Karin
    Hellström, Ann
    Jakobsson, Peter
    Lundgren, Pia
    Tornqvist, Kristina
    Wallin, Agneta
    Holmström, Gerd
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Regional differences in screening for retinopathy of prematurity in infants born before 27 weeks' gestation in Sweden: the EXPRESS study2014Ingår i: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 92, nr 4, s. 311-315Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose:  The primary aim was to analyse regional incidences of retinopathy of prematurity (ROP) and frequencies of treatment and their relation to perinatal risk factors during a 3-year period. A secondary aim was to study adherence to the study screening protocol in the different regions.

    Methods:  A population-based study of neonatal morbidity in extremely preterm infants in Sweden (EXPRESS) was performed during 2004–2007. Screening for ROP was to start at postnatal age 5 weeks and to continue weekly until the retina was completely vascularized or until regression of ROP. Logistic regression analyses were used for evaluation of differences in incidence of Any ROP, ROP 3 or more and ROP Type 1 between the seven regions of the country.

    Results:  The regional incidence of ROP varied between 54% and 92% for Any ROP, between 25% and 43% for ROP stage 3 or more and between 8% and 23% of infants with ROP Type 1, all of whom were treated. There was no significant difference between the regions regarding ROP Type 1, even when adjusting for known risk factors for ROP.

    Conclusion:  The heterogeneity between the regions regarding the incidence of ROP was reduced with increasing severity of ROP, and there was no heterogeneity regarding frequency of treatment for ROP, which is the most important issue for the children. We cannot exclude observer bias regarding mild ROP and ROP stage 3 in this study.

  • 26.
    Austeng, Dordi
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Källen, Karin
    Tornbladsinstitutet, Lund University.
    Hellström, Ann
    Section of Pediatric Ophthalmology, The Queen Silvia Children's Hospital, Sahlgrenska Academy, University of Gothenburg .
    Tornqvist, Kristina
    Department of Ophthalmology, Lund University Hospital.
    Holmström, Gerd E.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Natural history of retinopathy of prematurity in infants born before 27 weeks' gestation in Sweden2010Ingår i: Archives of ophthalmology (1960), ISSN 0003-9950, Vol. 128, nr 10, s. 1289-1294Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: To investigate the natural history of retinopathy of prematurity (ROP) in 506 extremely preterm infants born before 27 weeks' gestation in Sweden during a 3-year period.

    Methods: A national population–based study was performed in Sweden from April 1, 2004, to March 31, 2007. According to the study protocol, initial eye examinations were to be performed at postnatal week 5, and examinations were repeated until the retina was completely vascularized or until criteria for treatment were met. The examinations were to be performed weekly, enabling study of the course and severity of ROP. In infants without ROP or with mild ROP without progression during the latest examinations, further examinations were performed weekly or every other week from postmenstrual age 35 weeks.

    Results: During the study, 368 infants (72.7%) developed ROP. Postmenstrual age at onset of ROP was significantly related to severity of ROP, even when controlling for gestational age (ie, the earlier the onset of ROP, the higher the risk of developing severe ROP). Site of onset of ROP was significantly related to gestational age at birth. The risk of nasal onset was almost doubled for every week of decrease in gestational age at birth. Nasal onset was associated with severe ROP, even after adjusting for gestational age at birth.

    Conclusion: This population-based study confirms results of the Cryotherapy for Retinopathy of Prematurity study and shows new correlations regarding time and site of onset of ROP, both of which are associated with disease severity.

  • 27. Ayala, Marcelo N.
    et al.
    Söderberg, Per G.
    St. Erik’s Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
    Reversal of reciprocity failure for UVR-induced cataract with vitamin E2005Ingår i: Ophthalmic Research, ISSN 0030-3747, E-ISSN 1423-0259, Vol. 37, nr 3, s. 150-155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: The authors have previously described that the photochemical reciprocity law does not apply for ultraviolet radiation (UVR)-induced cataract. The aim of this study was to elucidate if failure of the reciprocity reverses with vitamin E (alpha-tocopherol) administration. METHODS: Altogether, 80 rats were divided into one group fed alpha-tocopherol and one control group. For each group, half of rats were exposed to UVR for 5 min and the remaining rats for 15 min. RESULTS: Lenses exposed to UVR for 5 min showed no difference in light scattering between alpha-tocopherol-treated and untreated groups. Lenses exposed to UVR for 15 min showed significant difference in light scattering between alpha-tocopherol-treated and untreated groups. CONCLUSIONS: Failure in exposure time-intensity reciprocity for UVR-induced cataract with exposures shorter than 30 min may be due to consumption of antioxidants in the lens.

  • 28. Ayala, Marcelo
    et al.
    Strid, Hilja
    Örebro universitet, Hälsoakademin.
    Jacobsson, Ulrika
    Söderberg, Per G.
    p53 expression and apoptosis in the lens after ultraviolet radiation exposure2007Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 48, nr 9, s. 4187-4191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: To localize p53 protein and active caspase-3 in the albino rat lens and to compare p53 mRNA and active caspase-3 expression in ultraviolet radiation (UVR) 300 nm exposed lenses and their contralateral nonexposed controls. METHODS: Ten Sprague-Dawley albino rats were unilaterally exposed to 8 kJ/m(2) UVR, and the contralateral eyes were left nonexposed. In total, four exposed lenses and their respective contralateral nonexposed lenses were analyzed by immunohistochemistry to localize p53 and active caspase-3. In addition, six exposed and contralateral nonexposed lenses were analyzed by real-time RT-PCR. Quantified p53 and caspase-3 expression were compared between the in vivo UVR 300 nm exposed lenses and the contralateral nonexposed lenses. RESULTS: All lenses exposed to UVR developed cataract. Immunohistochemistry showed that p53 and active caspase-3 were localized in the lens epithelial cells. Quantified p53 and caspase-3 expression were significantly higher in lenses exposed to UVR than in nonexposed lenses. CONCLUSIONS: p53 and caspase-3 expression increase in lens epithelial cells after UVR exposure. In the lens, apoptosis induced by UVR may be associated with increased p53 expression.

  • 29. Backstrom, Gunnie
    et al.
    Lundberg, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Behndig, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Oftalmiatrik.
    Intracameral acetylcholine effectively contracts pupils after dilatation with intracameral mydriatics2013Ingår i: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 91, nr 2, s. 123-126Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To determine whether intracameral acetylcholine can contract pupils dilated with intracameral mydriatics in phacoemulsification cataract surgery. Methods: A total of 60 patients were included in this prospective randomized masked study performed at ornskoldsviks Hospital Eye Clinic. The patients were randomized and were given either topical placebo and an intracameral mydriatic solution (ICM) (cyclopentolate 0.1%, phenylephrine 1.5% and xylocaine 1%) (n=30) or topical mydriatics (TM) (cyclopentolate 0.85% and phenylephrine 1.5%) and xylocaine 1% intracamerally (n=30) at the start of surgery. After intraocular lens (IOL) implantation, 0.15ml 1% acetylcholine was given intracamerally in all cases. The pupil size was registered preoperatively, 45seconds after intracameral injection, after ophthalmic viscosurgical device (OVD) evacuation, 30seconds after acetylcholine injection, 2min after acetylcholine injection and the day after surgery. Results: The pupil contraction and pupil size after acetylcholine injection showed no significant differences at 30seconds (contraction 1.0 +/- 0.4 in ICM group versus 0.9 +/- 0.4 in TM group; p=0.75; size 4.8 +/- 1.1 in the ICM group versus 5.2 +/- 1.1 in the TM group; p=0.24) or at 2min (contraction 1.5 +/- 0.6 in the ICM group versus 1.4 +/- 0.6 in the TM group; p=0.63; size 4.3 +/- 0.9 in the ICM group versus 4.7 +/- 1.0 in the TM group; p=0.13). No difference in baseline pupil size after ophthalmic viscosurgical device (OVD) evacuation was seen between the two groups (5.8 +/- 0.9 in the ICM group versus 6.1 +/- 1.2 in the TM group; p=0.28). Conclusion: We here show that intracameral acetylcholine contracts pupils as effectively after dilatation with intracameral mydriatics as after dilatation with topical mydriatics. Cataract surgeons can feel comfortable and safe when using intracameral mydriatics, even if pupil contraction with acetylcholine should be required.

  • 30.
    Baptista, Antonio M. G.
    et al.
    University of Minho, Portugal.
    Joel, Monteiro
    Centro Hospitalar do Alto Ave, Portugal.
    Vieira, Marco
    Centro Hospitalar do Alto Ave, Portugal.
    Reimão, Pedro
    Centro Hospitalar do Alto Ave, Portugal.
    Rocha, Paulo
    University of Porto, Portugal.
    Rocha-Sousa, Amandio A.
    University of Porto, Portugal.
    Freitas, Cristina
    Hospital de Braga, Portugal.
    Macedo, António Filipe
    University of Minho, Portugal.
    Marques, Ana Patricia
    Nova University of Lisbon, Portugal.
    Santana, Rui
    Nova University of Lisbon, Portugal.
    Causes of Vision Impairment in Portugal: A hospital based study2015Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 56, nr 7, artikel-id 2118Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose 

    Causes of vision impairment (VI) are influenced by factors such as race or socio-economic circumstances. Because of this collecting national information is important for planning reduction of vision loss. The aim of this study was to determine causes of vision impairment in a population visiting ophthalmology departments in public hospitals in Portugal.

    Methods 

    This study was designed according with the guidelines of the Vancouver Economic Burden of Vision Loss Group (IOVS, 2010, V51/4/1801). Recommendations are to collect hospital data during 1 year to determine causes of VI. We selected four public hospitals that are expected to have over 120-140K appointments per year. Files are analysed weekly to detect patients with vision impairment. Inclusion criteria are: visual acuity with the current refractive correction equal or less than 0.5 (20/40) in the better-seeing eye and/or a visual field of less than 20 degrees. Patients were selected by trained hospital staff (medics and orthoptists) and inserted in a database. Diagnoses were classified according the ICD9. Data collected included fundamental demographic information, main diagnosis, secondary diagnosis and comorbidities.

    Results 

    We have now 2462 patients selected that correspond to 4 to 33 weeks of data collection. The number of weeks is variable because we did not start all hospitals simultaneously. From the current number of cases detected, 58% are female, 1.9% are under 20, 8.2% are between 20 and 50 and 89.9% are 50 years or older. The leading causes of vision impairment among these patients are diabetic retinopathy (DR), cataract (C), glaucoma (GC) and age-related macular degeneration (AMD). Using the North American definition of VI the proportions are 26.8% for DR, 25.5% for C, 10.4% for GC and 8.2% for AMD. The remaining causes of VI have percentages below 5% and in total they correspond to approximately 29% of the cases detected.

    Conclusions 

    Our results show that the most common causes of vision impairment are eye diseases related with systemic conditions and aging of the population. Vision impairment was relatively low under the age of 20 and the causes were mostly inherited diseases. Numbers reported now will be more accurate at the end of the study but they already highlight the importance of targeting conditions such as diabetes.

  • 31.
    Baptista, António M. G.
    et al.
    University of Minho, Portugal.
    Sousa, Raul A. R. C.
    Rocha, Filomena A. S. Q.
    Sepúlveda Fernandes, Paula
    Macedo, António Filipe
    University of Minho, Portugal.
    The macular photostress test in diabetes, glaucoma, and cataract2013Ingår i: 8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications, SPIE - International Society for Optical Engineering, 2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose. The photostress recovery time test (PSRT) has been widely reported as a helpful screening clinical tool. However, the poor standardization of its measurement technique remains to be a limitation among clinicians. The purpose of this study is to apply a recommended clinical technique to measure the PSRT in some of the most commons eye diseases to ascertain whether these diseases affect the PSRT values. Methods. One hundred and one controls and 105 patients, with diagnosed diabetes (without visible signs of diabetic retinopathy), primary open angle glaucoma (POAG) or cataracts underwent photostress testing. The test was performed with a direct ophthalmoscope for illuminating the macula for 30 seconds. Participants belonged to three age classes: A, B and C; and were divided into four groups: control, diabetic, POAG and cataract. The age range for A, B and C classes were respectively 43-54, 55-64 and 65-74 years. The groups were also further compared within each age class. In addition, the influence of age on PSRT was evaluated using the control group. Results. Results demonstrate that PSRT changes with age (p<0.02). In class A, diabetic group had a faster PSRT than control group, (mean ± standard deviation) 20.22±7.51 and 26.14±8.34 seconds. The difference between these groups was statistical significant (t-test, p=0.012). Cataract and POAG groups did not affect the PSRT significantly. Conclusions. The technique used for the Photostress showed that diabetics, younger than 54 years, may have faster PSRT and that, aging delays PSRT

  • 32.
    Barth, Henrik
    et al.
    Department of Ophthalmology, Lund University Hospital, Biomedicinskt centrum (BMC), Lund, Sweden.
    Crafoord, Sven
    Örebro universitet, Institutionen för medicinska vetenskaper. Department of Ophthalmology, Örebro University Hospital, Örebro, Sweden.
    Andréasson, Sten
    Department of Ophthalmology, Lund University Hospital, Biomedicinskt centrum (BMC), Lund, Sweden.
    Ghosh, Fredrik
    Department of Ophthalmology, Lund University Hospital, Biomedicinskt centrum (BMC), Lund, Sweden.
    A cross-linked hyaluronic acid hydrogel (Healaflow(®)) as a novel vitreous substitute2016Ingår i: Graefe's Archives for Clinical and Experimental Ophthalmology, ISSN 0721-832X, E-ISSN 1435-702X, Vol. 254, nr 4, s. 697-703Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: Vitrectomy requires the substitution of the natural vitreous, as well as tamponading of retinal breaks. Clinically available alternatives such as gas and silicone oil have side effects such as inflammation, secondary glaucoma, cataract, and a need for head posturing. In this study, a hydrogel of cross-linked sodium hyaluronic acid (Healaflow(®)) is evaluated for use as a novel vitreous substitute.

    Methods: A combined 25-20-gauge pars plana vitrectomy with posterior vitreous detachment was performed in the right eye of twelve pigmented rabbits, with subsequent injection of approximately 1 ml Healaflow(®). Clinical evaluation, measurement of intraocular pressure (IOP), and full-field ERG were performed postoperatively. The rabbits were sacrificed at different time-points between 42 and 105 days. After enucleation, the eyes were examined macroscopically, photographed, and prepared for histological examination with routine microscopy and immunohistochemistry.

    Results: Healaflow(®) was successfully used with standard surgical procedures and remained translucent but did lose most of its viscosity during the postoperative period. One rabbit was lost due to unrelated causes. In two eyes iatrogenic partial retinal detachments were seen, and in two eyes significant cataract developed due to intra-operative complications. ERG-recordings revealed no toxic effect on rod or cone function. Routine microscopy and immunohistochemistry demonstrated normal morphology with some Müller cell activation (up-regulation of glial acidic fibrillary protein, GFAP) compared to unoperated eyes and no significant DNA-fragmentation (TUNEL-assay).

    Conclusions: Healaflow® did not affect retinal morphology or function negatively during long-term use as a vitreous substitute, making it highly interesting in this setting. An estimated retention time of a few weeks suggests potential for use as a short-term tamponade. Future work will include an increased ratio of cross-linking to prolong the structural integrity of the gel.

  • 33.
    Barth, Henrik
    et al.
    Department of Ophthalmology, Lund University, Lund, Sweden .
    Crafoord, Sven
    Örebro universitet, Institutionen för läkarutbildning. Department of Ophthalmology, Örebro University Hospital, Örebro, Sweden.
    O'Shea, Timothy M.
    Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, USA .
    Pritchard, Christopher D.
    Harvard-Massachusetts Institute of Technology, Division of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, USA .
    Langer, Robert
    Harvard-Massachusetts Institute of Technology, Division of Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, USA .
    Ghosh, Fredrik
    Department of Ophthalmology, Lund University, Lund, Sweden .
    A new model for in vitro testing of vitreous substitute candidates2014Ingår i: Graefe's Archives for Clinical and Experimental Ophthalmology, ISSN 0721-832X, E-ISSN 1435-702X, Vol. 252, nr 10, s. 1581-1592Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To describe a new model for in vitro assessment of novel vitreous substitute candidates.

    Methods: The biological impact of three vitreous substitute candidates was explored in a retinal explant culture model; a polyalkylimide hydrogel (Bio-Alcamid (R)), a two component hydrogel of 20 wt.% poly (ethylene glycol) in phosphate buffered saline (PEG) and a cross-linked sodium hyaluronic acid hydrogel (Healaflow (R)). The gels where applied to explanted adult rat retinas and then kept in culture for 2, 5 and 10 days. Gel-exposed explants were compared with explants incubated under standard tissue culture conditions. Cryosections of the specimens were stained with hematoxylin and eosin, immunohistochemical markers (GFAP, Vimentin, Neurofilament 160, PKC, Rhodopsin) and TUNEL.

    Results: Explants kept under standard conditions as well as PEG-exposed explants displayed disruption of retinal layers with moderate pyknosis of all neurons. They also displayed moderate labeling of apoptotic cells. Bio-Alcamid (R)-exposed explants displayed severe thinning and disruption of retinal layers with massive cell death. Healaflow (R)-treated explants displayed normal retinal lamination with significantly better preservation of retinal neurons compared with control specimens, and almost no signs of apoptosis. Retinas exposed to Healaflow (R) and retinas kept under standard conditions showed variable labeling of GFAP with generally low expression and some areas of upregulation. PEG-exposed retinas showed increased GFAP labeling and Bio-Alcamid (R)-exposed retinas showed sparse labeling of GFAP.

    Conclusions: Research into novel vitreous substitutes has important implications for both medical and surgical vitreoretinal disease. The in vitro model presented here provides a method of biocompatibility testing prior to more costly and cumbersome in vivo experiments. The explant culture system imposes reactions within the retina including disruption of layers, cell death and gliosis, and the progression of these reactions can be used for comparison of vitreous substitute candidates. Bio-Alcamid (R) had strong adverse effects on the retina which is consistent with results of prior in vivo trials. PEG gel elicits reactions similar to the control retinas whereas Healaflow (R) shows protection from culture-induced trauma indicating favorable biocompatibility.

  • 34.
    Barth, Henrik
    et al.
    Lund Univ, Dept Ophthalmol, Lund, Sweden..
    Crafoord, Sven W.
    Örebro universitet, Institutionen för medicinska vetenskaper. Region Örebro län. Dept Ophthalmology.
    Arner, Karin
    Lund Univ, Dept Ophthalmol, Lund, Sweden..
    Ghosh, Fredrik K.
    Lund Univ, Dept Ophthalmol, Lund, Sweden..
    Cellular CD68 and CD45r0 positive inflammatory responses of vitrectomy with vitreous substitutes2016Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 57, nr 12Artikel i tidskrift (Refereegranskat)
  • 35.
    Bartuma, Katarina
    et al.
    Karolinska Inst, St Erik Eye Hosp, Dept Vitreoretinal Dis, Stockholm, Sweden..
    Pal, Niklas
    Karolinska Inst, Dept Pediat, Astrid Lindgren Childrens Hosp, S-10401 Stockholm, Sweden..
    Kosek, Sonja
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper. Uppsala Univ, Uppsala, Sweden..
    Holm, Stefan
    Karolinska Inst, Dept Pediat, Astrid Lindgren Childrens Hosp, S-10401 Stockholm, Sweden..
    All-Ericsson, Charlotta
    Karolinska Inst, St Erik Eye Hosp, Dept Vitreoretinal Dis, Stockholm, Sweden..
    A 10-year experience of outcome in chemotherapy-treated hereditary retinoblastoma2014Ingår i: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 92, nr 5, s. 404-411Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: The aim is to report the 10-year retrospective experience of systemic chemotherapy for a population-based group of patients with hereditary retinoblastoma at a national referral centre. The outcomes include control rates, treatment side-effects, adjuvant therapy, failure rate, survival, secondary cancers and visual acuity. Methods: All patients (n = 24, 46 eyes) diagnosed with retinoblastoma and treated with systemic chemotherapy at a national referral centre during 2001-2011 were included. Data were extracted from medical records. Results: The patients were followed for a mean of 60 months (range 13-144). Four-six cycles of VEC was administered to all newly diagnosed group B/C/D/E eyes with bilateral disease and 83% (38 of 46) responded to the treatment. None of the patients discontinued chemotherapy because of adverse reactions. Altogether 26% (12 of 46) of the eyes received second-line therapy (other than thermotherapy, cryotherapy and chemotherapy). The failure rate was 35% (16 of 46) and mortality rate 0%. None of the patients developed CNS manifestations (metastases or trilateral retinoblastoma). One of the patients developed a second primary tumour (osteosarcoma) 4 years following retinoblastoma diagnosis. Altogether 17% (4 of 24) patients received radiation therapy, 28% (13 of 46) of the eyes had to be enucleated, and one patient underwent bilateral enucleation. The age-correlated visual acuity was mean of 73% of expected visual acuity. Conclusion: Group A/B retinoblastomas have a distinct chemotherapy response, while group C/D/E tumours do not respond as well. The success rate was 65%; while patients have a good prognosis for life, approximately one-third of all hereditary cases received radiation therapy or underwent enucleation.

  • 36.
    Baskaran, Karthikeyan
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Optimal Use of Peripheral Vision2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    People who lose their central vision have to rely on their peripheral vision for all visual tasks. The ability to resolve fine details in the periphery is reduced due to retinal limitations and the optical aberrations arising from the use of off-axis vision. The aim of this work is to improve vision by enhancing the image quality at the preferred retinal locus by means of correcting the optical errors. The focus of this thesis has been to measure and correct peripheral optical errors, as well as to evaluate their impact on resolution acuity in both normal and central visual field loss subjects.

     In order to measure peripheral optics we employed a COAS HD VR open view aberrometer which is based on the Hartmann-Shack principle. Psychophysical methods were used to evaluate peripheral grating resolution acuity. We assessed the repeatability of the wavefront sensor in measuring the peripheral ocular aberrations. The symmetry of peripheral ocular aberrations between the left and right eyes was examined. The influence of age on peripheral ocular aberrations was also investigated. We evaluated peripheral vision with sphero-cylindrical correction in healthy eyes and performed the first adaptive optics aberration correction at the preferred retinal locus of a single central visual field loss subject.

     We found that the aberrometer was repeatable and reliable in measuring peripheral ocular aberrations. There was mirror symmetry between the two eyes for most of the peripheral aberration coefficients. Age had a significant influence on peripheral ocular aberrations; there were larger amounts of higher-order aberrations in old eyes than in young eyes. Peripheral low contrast resolution acuity improved with peripheral refractive correction in subjects who had higher amounts of off-axis astigmatism. Finally, adaptive optics aberration correction improved both high and low contrast resolution acuity measured at the preferred retinal locus of the single low vision subject.

     Because of their versatility, open view aberrometers will hopefully be a standard clinical instrument at low vision clinics as they allow for measurements to be rapidly performed at any location in the visual field. The existence of off-axis astigmatism should be better communicated within the low-vision rehabilitation community. Currently, the off-axis refractive errors can be corrected with conventional methods and we hope that the higher-order aberrations can also be corrected in a more realistic ways in the future.  

     In conclusion, this thesis has shown that peripheral visual function can be improved by optical correction. The findings of this thesis have broadened the knowledge of peripheral optical errors and their influence on vision.

  • 37.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Calabrèse, Aurélie
    Castet, Eric
    Moreno, Laura
    Silva, Marta
    Macedo, Antonio F.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Scoring reading parameters: an inter-rater reliability study using the MNREAD test2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Aim: Estimating MNREAD parameters such as Critical Print Size (CPS) and Maximum Reading Speed (MRS) - using the time taken to read blocks of text - often requires subjective analysis of the reading profile. Depending on the rater, parameters may be over- or under-estimated, resulting in difficult or even impossible between-study comparisons. The aim of this project was to evaluate the inter-rater reliability of MNREAD parameters in subjects with visual impairment. Methods: Reading times for the Portuguese version of the MNREAD chart from 32 subjects, reading binocularly were analyzed. Reading speed was computed by a single experimenter (AFM) using reading time and number of errors. Based on reading speeds, three experimented raters (AFM, AC and KB) computed MRS and CPS using the following method. CPS was defined as the print size at which subsequent smaller print sizes were read at 1.96 x standard deviation slower than the mean of the preceding print sizes; MRS was estimated as the mean reading speed for sentences in print larger than the CPS. Inter-rater reliability was assessed using intra-class correlation (ICC) coefficient for both MRS and CPS for all three raters. Results: Near acuity range was 0.14-1.9 logMAR. The average measure ICC for CPS was 0.896 with a 95% CI from 0.814 to 0.946 (p< 0.001). The average measure ICC for MRS was 0.984 with a 95% CI from 0.970 to 0.992 (p< 0.001). Conclusion: A high degree of reliability was found between the three raters for both CPS and MRS. Even though some small variability exists this may be due to raters’ high-level experience with MNREAD data. Future directions will involve: 1) including more raters with various level of experience in MNREAD rating; 2) investigating the degree of inter-rater reliability for raters using different estimation methods.

  • 38.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Ekblad, Johan
    Inde, Krister
    Melis-Dankers, Bart
    Driving performance in participants with quadrantanopia and hemianopia in Sweden: a closed circuit driving track study2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Background: The ability to drive a car is one of the important aspect of a person’s independent lifestyle. People with visual field defects after stroke or traumatic brain injury (TBI) have more limitations in driving. In Sweden, they are not allowed to drive and their driving licenses are revoked. The Swedish transport agency does not allow any on-road test for them to prove their practical fitness to drive. Therefore, the aim was to evaluate driving performance in participants with visual field defects after TBI in a closed circuit driving track.Methods: Eleven participants with varying degrees of quadrantanopia and hemianopia after TBI were recruited for this study. The mean age of the participants was 58 ±13.7 years (37 - 73 years). All participants underwent 10 weeks of explorative saccadic training at the hospital prior to driving assessment. Driving performance were assessed by two driving instructors and they graded the participants from 1 (fail) to 5 (excellent) on the following five categories: maneuvering the vehicle, safety margin, traffic rules, scanning for potential hazards and reacting to situations. The subject passed the driving test only if they scored 3 or more in each category.Results: Five (45%) out of 11 participants passed the driving test and they were adjudged as fit to drive. Remaining six (55%) participants failed at least in one category. Three of them failed in visual scanning, two failed in maneuvering and one failed in both the aforementioned categories as well as safety margin.Discussion: A rehabilitation program aimed at improving safe driving should be implemented and an on-road assessment of fitness to drive should be allowed in Sweden for this population in future.Conclusion: The decision on practical fitness to drive cannot be based solely on the presence of visual field defect and an on-road assessment is required.

  • 39.
    Baskaran, Karthikeyan
    et al.
    Indiana University, USA.
    Elsner, Ann E.
    Indiana University, USA ; Aeon Imaging, USA.
    Muller, Matthew S.
    Aeon Imaging, USA.
    Haggerty, Bryan P.
    Indiana University, USA.
    Papay, Joel A.
    Indiana University, USA.
    Gast, Thomas
    Indiana University, USA ; Aeon Imaging, USA.
    Litvin, Taras V.
    University of California Berkeley, USA.
    Ozawa, Glen Y.
    University of California Berkeley, USA.
    Cuadros, Jorge
    University of California Berkeley, USA.
    Petrig, Benno L.
    Aeon Imaging, USA.
    Stability of fixation in diabetes patients with and without clinically significant macular edema2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose - Eye diseases affecting central vision impair fixation and interfere with day-to-day tasks such as reading. Diabetic retinopathy and clinically significant macular edema (CSME) are leading causes of visual impairment in diabetes patients. The aim of this study is to find whether diabetic patients with CSME have poorer fixation stability compared to patients without CSME, by analyzing the fundus images obtained from the Laser Scanning Digital Camera (LSDC).

    Methods - Two hundred underserved, diabetic patients were screened for diabetic retinopathy at the Eastmont Wellness Center within the EyePACS telemedicine network, using LSDC. One eye of each patient who had diabetic retinopathy was included in this study. Non-mydriatic color fundus photos were classified for presence of CSME by two independent, certified EyePACS graders. The first 50 patients (25 males &amp; 25 females) with CSME were selected and 50 (27 males &amp; 23 females) diabetic patients without CSME were selected as controls. Mean age was 59 (±9) years for patients with CSME and was 55 (±10) years for patients without CSME. The subjects included 53% Hispanics, 26% African Americans and 21% other. A series of 20 images (36 deg field, 1024 X 1024 pixels, and 850 nm) were acquired at 11 fps. Eye positions were obtained by selecting a region of interest in the first image of each series and aligning the remaining images to that region by cross-correlation. The bi-contour ellipse area (BCEA) and the standard deviation of the Euclidean distance (SDED) were used to quantify fixation stability.

    Results - The fixation stability for patients with CSME was significantly worse than for those without CSME (t test: p &lt; 0.001, 0.007 for BCEA and SDED, respectively). The mean fixation stability obtained by the BCEA metric was 2.74 (±0.40) log(minArc2) and 2.34 (±0.42) log(minArc2) for patients with and without CSME, respectively. For SDED the mean was 48.4 (±28.8) microns and 34.6 (±20.4) microns for patients with and without CSME, respectively. The correlation with age was not significant for either group (R2 = 0.052, 0.011).

    Conclusions - Diabetic patients with CSME had poorer fixation stability than patients without CSME for both metrics. Fixation stability is a potential tool for assessing macular function and could be used for tracking the treatment and progression of macular edema.The LSDC images provide one method to quantify fixation stability rapidly.

  • 40.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Inde, Krister
    Ekblad, Johan
    Melis-Dankers, Bart
    Closed circuit driving performance in persons with quadrantanopia and hemianopia in Sweden2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    In Sweden, persons with homonymous visual field defects (HVFDs) are not allowed to drive and usually their driving licences are revoked. Although earlier studies (de Haan et al. 2014; Elgin et al. 2010) have shown that HVFDs do not necessarily impair practical fitness to drive, the Swedish transport agency does not allow them any on-road driving testing to prove their practical fitness to drive. The aim of this study was to evaluate driving performance in participants with visual field defects after acquired brain injury in a closed circuit driving track. Eleven former drivers with varying degrees of quadrantanopia and hemianopia after acquired brain damage were recruited for this study from the stroke rehabilitation department at Kalmar County Hospital. The median age of the participants was 55 years and their age ranged from 37 to 73 years. Driving performance was assessed by two experienced driving instructors. They graded the participants on a scale from 1 (major faults) to 5 (excellent) on the following five categories: manoeuvring the vehicle, risk assessment, traffic rules, visual scanning and situation awareness. The subject would pass the driving test only if they had scored 3 or more in each category. The subjects who passed the closed circuit driving track test were evaluated further with a driving simulator. Five (45%) out of 11 participants passed the driving test and were adjudged as fit to drive. The remaining six (55%) participants failed in at least one category. Three failed in visual scanning, two failed in manoeuvring and one failed in both the aforementioned categories as well as risk assessment. Three subjects who passed the closed circuit driving track test were also evaluated in a driving simulator. Out of the three subjects, only one was able to complete and pass the evaluation while the remaining two participants aborted the evaluation due to simulator sickness. Homonymous visual field defects do not necessarily impair fitness to drive. Therefore, an on-road assessment of practical fitness to drive should be allowed in Sweden for this population in the near future. The decision on practical fitness to drive cannot be based solely on the presence of visual field defects. A rehabilitation program aimed at improving safe driving should be put into practice with an on-road driving training and assessment procedure. It should be developed and implemented by experienced traffic inspectors as a complementary part of the decision to either issue or revoke a driving licence for this population.

  • 41.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Inde, Krister
    SMS Projektgrupp, .
    SYAB Kalmar, .
    SMS resultatrapporten2015Rapport (Refereegranskat)
  • 42.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Olsson, Roger
    Theagarayan, Baskar
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för medicin och optometri (MEO).
    Effect of accommodation on peripheral refraction in myopes and emmetropes using a COAS-HD VR open field aberrometer.2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose To investigate the effect of accommodation on both central and peripheral refractive errors in myopes compared to emmetropes using a COAS-HD VR open field aberrometer. Methods 15 myopic subjects (-1.50 D to -8.25 D) and 14 emmetropic subjects (+0.75 D to -0.25 D) participated in this study. The mean age of the myopic group was 24.3 ± 5.7 years and for the emmetropic group was 23.9 ± 5.7 years. Central and peripheral refraction were measured with a COAS-HD VR open field instrument at seven different eccentricities from 0° to ± 30° in 10° steps for three different accommodative demands 0.33 D, 2.50 D and 4.0 D during monocular viewing. The myopic subjects were corrected with soft contact lenses and the measurements were performed on the right eye for a 3 mm pupil diameter for both groups. Relative peripheral refractive error (RPRE) was calculated for all three accommodative demands for both groups. Results Repeated measures ANOVA showed no significant difference in RPRE across eccentricities or between accommodation demands in the myopes (pÂż0.05). The myopic group had minimal hyperopic shift in the periphery for all three accommodative demands. The largest mean hyperopic shift was 0.37 D at 30° nasal retina for an accommodative demand of 4.0 D. On the other hand, the emmetropic group became relatively myopic at peripheral eccentricities, from 20° onwards for all three accommodative demands. The largest mean myopic shift was 1.01 D at 30° temporal retina for an accommodative demand of 2.50 D. Conclusion In the myopic group, we did not find any significant reduction in hyperopic shift in the periphery with accommodation. The emmetropic group showed myopic shift in the periphery for all three accommodative demands with temporal retina being more myopic than nasal retina.

  • 43.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Rosen, R.
    Lewis, Peter
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Unsbo, P.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Benefit of Adaptive Optics Aberration Correction at Preferred Retinal Locus2012Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 89, nr 9, s. 1417-1423Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE.: To investigate the effect of eccentric refractive correction and full aberration correction on both high- and low-contrast grating resolution at the preferred retinal locus (PRL) of a single low-vision subject with a long-standing central scotoma. METHODS.: The subject was a 68-year-old women with bilateral absolute central scotoma due to Stargardt disease. She developed a single PRL located 25 degrees nasally of the damaged macula in her left eye, this being the better of the two eyes. High- (100%) and low-contrast (25 and 10%) grating resolution acuity was evaluated using four different correction conditions. The first two corrections were solely refractive error corrections, namely, habitual spectacle correction and full spherocylindrical correction. The latter two corrections were two versions of adaptive optics corrections of all aberrations, namely, habitual spectacle correction with aberration correction and full spherocylindrical refractive correction with aberration correction. RESULTS.: The mean high-contrast (100%) resolution acuity with her habitual correction was 1.06 logMAR, which improved to 1.00 logMAR with full spherocylindrical correction. Under the same conditions, low-contrast (25%) acuity improved from 1.30 to 1.14 logMAR. With adaptive optics aberration correction, the high-contrast resolution acuities improved to 0.89/0.92 logMAR and the low-contrast acuities improved to 1.04/1.06 logMAR under both correction modalities. The low-contrast (10%) resolution acuity was 1.34 logMAR with adaptive optics aberration correction; however, with purely refractive error corrections, she was unable to identify the orientation of the gratings. CONCLUSIONS.: Correction of all aberrations using adaptive optics improves both high- and low-contrast resolution acuity at the PRL of a single low-vision subject with long-standing absolute central scotoma

  • 44. Baskaran, Karthikeyan
    et al.
    Rosén, Robert
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Lewis, Peter
    Unsbo, Peter
    Gustafsson, Jörgen
    Benefit of Adaptive Optics Aberration Correction at Preferred Retinal Locus2012Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 89, nr 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose: To investigate the effect of eccentric refractive correction and full aberration correction on both high and low contrast grating resolution at the preferred retinal locus (PRL) of a single low vision subject with a longstanding central scotoma.

    Methods: The subject was a 68 year-old female with bilateral absolute central scotoma due to Stargardt’s disease. She has developed a single PRL located 25° nasally of the damaged macula in her left eye, this being the better of the two eyes. High- (100%) and low contrast (25% & 10%) grating resolution acuity was evaluated using four different correction conditions. The first two corrections were solely refractive error corrections; namely habitual spectacle correction and full sphero-cylindrical correction. The latter two corrections were two versions of adaptive optics corrections of all aberrations; namely full sphero-cylindrical refractive correction with additional aberration correction and habitual spectacle correction with aberration correction.

    Results: The mean high contrast (100%) resolution acuity with her habitual correction was 1.06 logMAR, which improved to 1.00 logMAR with full sphero-cylindrical correction. Under the same conditions, low contrast (25%) acuity improved from 1.30 logMAR to 1.14 logMAR. With adaptive optics aberration correction, the high contrast resolution acuities improved to 0.92/0.89 logMAR and the low contrast acuities, to 1.06/1.04 logMAR under both correction modalities. The low contrast (10%) resolution acuity was 1.34 logMAR with adaptive optics aberration correction; however, with purely refractive error corrections she was unable to identify the orientation of the gratings.

    Conclusion: Correction of all aberrations using adaptive optics improves both high and low contrast resolution acuity at the PRL of a single low vision subject with longstanding absolute central scotoma.

  • 45.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Theagarayan, Baskar
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Carius, Staffan
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för datavetenskap, fysik och matematik, DFM.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Influence of age on peripheral aberration2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    The purpose of this study is to compare peripheral higher order aberrations in young

    and old emmetropic eyes across the horizontal (±40°) and inferior (–20°) visual field.

    Introduction

     

     

    People with central visual field loss use eccentric fixation for various visual tasks.

    Recently studies have shown that the correction of lower order aberrations (defocus &

    astigmatism) can improve eccentric vision in subjects with central visual field loss

    (CFL)[1]. The CFL subjects mostly correspond to older age groups who use eccentric

    fixation angles up to 20°–30°. While there have been studies comparing the off-axis

    lower order aberrations in normal young and old subjects[2], there is only one recent

    study, which has compared off-axis higher order aberrations in normal young and old

    emmetropic eyes up to 20° (horizontal and vertical) eccentricity[3]. In this study we

    have measured off-axis aberrations in a group of 10 young (23 ± 3 years) and 10 old

    (57 ± 4 years) emmetropes. The aberrations of the right eye were measured using

    COAS-HD VR Hartmann-Shack aberrometer in steps 10° out to ± 40° horizontally and

    –20° inferiorly in the visual field. Subjects rotated the eyes to view the fixation targets,

    which were red light emitting diodes, placed at 3 meter from the eye. The aberrations

    were quantified for a pupil area 5 mm in diameter.

    Discussion

     

     

    Mixed between-within subject’s analysis of variance of the horizontal coma C13

    showed that there was a statistically significant difference between age groups

    (p<0.05). The coma increased linearly in both groups from nasal to temporal visual

    field. The rate of change was greater in the old (slope = –0.027 μm/deg) compared

    to the young (slope = –0.012 μm/deg) emmetropes. In the inferior visual field,

    vertical coma C-13 changed linearly in both groups with higher values in old (slope =

    0.015 μm/deg) compared to young (slope = 0.006 μm/deg). The mean spherical

    aberration was positive in older emmetropes (0.053 μm) compared to young

    emmetropes (-0.030 μm). The HO RMS showed a quadratic increase in the

    periphery for both age groups. The HO RMS was greater in older emmetropes but it

    was not statistically significant (p>0.05) when compared to young emmetropes.

     

    Conclusions

     

     

    Our results show that there is an increase in coma, spherical aberration, and HO

    RMS with age in the periphery.

  • 46.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Theagarayan, Baskar
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Carius, Staffan
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för datavetenskap, fysik och matematik, DFM.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Measurement of Off-axis Refraction with a Commercial Open Field Aberrometer2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    Purpose:

    People with central visual field loss (CFL) use their remaining peripheral vision in order to see better when performing various visual related tasks. At large off-axis angles, the eccentric vision can be limited both by the low resolution capacity of the peripheral retina and by the optical aberrations caused due to oblique angles. Previous work has shown that eccentric correction of induced off-axis astigmatism can improve vision in a preferred retinal location (PRL) for people with CFL. However, the eccentric refraction is often difficult to determine with traditional refractive methods. This work therefore shows the use of a commercially available wavefront sensor to measure fast and reliable off-axis refraction. Data on off-axis refraction is also of interest in the field of myopia research.

    Methods:

    We used the new open-field high-definition complete ophthalmic analysis system, COAS HD -VR, to evaluate off-axis refraction. Using the special Vision Research tool in this system stimulus (fixation objects) can be presented in a large part of the visual field. The instrument can measure out to 40 degrees in the horizontal visual field and 20 degrees in the vertical visual field with a range from sphere +7 D to − 17 D. It measures astigmatism up to 10 D. This instrument also allows natural binocular viewing without obstacles. Aberrations of the right eye of 30 emmetropes (24 ± 4 years) were studied. Off-axis refraction and higher order (HO) aberrations were measured in steps of 10° out to ± 30° in the horizontal visual field

    Results:

    The first data on young emmetropic eyes with this new instrument showed promising results for low (LO) and higher order (HO) aberrations in the peripheral visual field. Of the LO aberrations, astigmatism increased significantly with the off–axis angle, from 0.25 D at 10° Nasal to 1.65 D at 30° Nasal. In the HO aberrations, coma (C13) showed a linear increase across the horizontal visual field (p < 0.05)

    Conclusions:

    The COAS HD-VR shows promising results and good usability for future research in evaluation of off-axis refraction. In future we believe the aberrometer can be used clinically to measure off-axis refractions in low vision patients.

  • 47.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Theagarayan, Baskar
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Carius, Staffan
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för datavetenskap, fysik och matematik, DFM.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Ocular Aberrations in the Peripheral Visual Field With a Commercial Open-View Aberrometer2010Ingår i: Investigative Ophthalmology and Visual Science, ISSN 0146-0404, E-ISSN 1552-5783, Vol. 51, nr 5, artikel-id 3951Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PurposeThe interest in off-axis aberrations has increased with the discovery of a possible link between myopia development and peripheral optics. The most common technology to measure the off-axis aberrations is a Shack-Hartmann wavefront aberrometer. This is the first study to report peripheral aberrations in a large sample of emmetropic population with a commercial open-view Shack-Hartmann aberrometer. MethodsThe commercial open-view Shack-Hartmann aberrometer COAS-HD VR was used to measure the aberrations in the peripheral vision. Aberrations of the right eye of 30 emmetropes (24 {+/-} 4 years) were studied. Off-axis aberrations were measured in steps of 10{degrees} out to {+/-} 30{degrees} in the horizontal visual field. The subjects turned their eye to view the off-axis fixation target (light emitting diode placed at 3 meters) during the measurement. The resulting wavefront aberrations were parameterized with Zernike coefficients for a 5 mm diameter pupil. All analyzes are reported according to optical society of America (OSA) recommended standards. ResultsAberrations from the 2nd to 6th order and the total higher-order root-mean-square (HO RMS) were analyzed using one-way ANOVA. The defocus C02 was significantly myopic in the nasal visual field (+20{degrees}, +30{degrees}) whereas there was no significant difference in the temporal visual field. Astigmatism C22 increased quadratically from {+/-}10{degrees} in the periphery and coma C13 showed a linear increase across the horizontal visual field (p < 0.05). The spherical aberration C04 and the total HO RMS showed a significant change at {+/-}30o. ConclusionsOur results showed that in young emmetropes there was a significant increase of HO RMS at {+/-}30{degrees}, which is expected. Astigmatism, horizontal coma, and spherical aberration vary systematically across the horizontal visual field in agreement with Seidel theory. The findings of our study with a large sample of emmetropic population agree with the previous studies done with laboratory built aberrometers.

  • 48.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Theagarayan, Baskar
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Carius, Staffan
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för datavetenskap, fysik och matematik, DFM.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Repeatability of Peripheral Aberrations in Young Emmetropes2010Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 87, nr 10, s. 751-759Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE.: The purpose of this study is to assess the intrasession repeatability of ocular aberration measurements in the peripheral visual field with a commercially available Shack-Hartmann aberrometer (complete ophthalmic analysis system-high definition-vision research). The higher-order off-axis aberrations data in young healthy emmetropic eyes are also reported.

    METHODS.: The aberrations of the right eye of 18 emmetropes were measured using an aberrometer with an open field of view that allows peripheral measurements. Five repeated measures of ocular aberrations were obtained and assessed in steps of 10 degrees out to +/-40 degrees in the horizontal visual field (nasal + and temporal -) and -20 degrees in the inferior visual field. The coefficient of repeatability, coefficient of variation, and the intraclass correlation coefficient were calculated as a measure of intrasession repeatability.

    RESULTS.: In all eccentric angles, the repeatability of the third- and fourth-order aberrations was better than the fifth and sixth order aberrations. The coefficient of variation was <30% and the intraclass correlation coefficient was >0.90 for the third and fourth order but reduced gradually for higher orders. There was no statistical significant difference in variance of total higher-order root mean square between on- and off-axis measurements (p > 0.05). The aberration data in this group of young emmetropes showed that the horizontal coma (C13) was most positive at 40 degrees in the temporal field, decreasing linearly toward negative values with increasing off-axis angle into the nasal field, whereas all other higher-order aberrations showed little or no change.

    CONCLUSIONS.: The complete ophthalmic analysis system-high definition-vision research provides fast, repeatable, and valid peripheral aberration measurements and can be used efficiently to measure off-axis aberrations in the peripheral visual field

  • 49. Baskaran, Karthikeyan
    et al.
    Unsbo, Peter
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Gustafsson, Jörgen
    Influence of Age on Peripheral Ocular Aberrations2011Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 88, nr 9, s. 1088-1098Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose. To compare peripheral lower and higher order aberrations across the horizontal (+/- 40 degrees) and inferior (-20 degrees) visual fields in healthy groups of young and old emmetropes. Methods. We have measured off-axis aberrations in the groups of 30 younger (24 +/- 3 years) and 30 older (58 +/- 5 years) emmetropes. The aberrations of OD were measured using the COAS-HD VR Shack-Hartmann aberrometer in 10 degrees steps to +/- 40 degrees horizontally and -20 degrees inferiorly in the visual field. The aberrations were quantified with Zernike polynomials for a 4 mm pupil diameter. The second-order aberration coefficients were converted to their respective refraction components (M, J(45), and J(180)). Mixed between-within subjects, analysis of variance were used to determine whether there were significant differences in the refraction and aberration components for the between-subjects variable age and the within-subjects variable eccentricity. Results. Peripheral refraction components were similar in both age groups. Among the higher order coefficients, horizontal coma (C(3)(1)) and spherical aberration (C(4)(0)) varied mostly between the groups. Coma increased linearly with eccentricity, at a more rapid rate in the older group than in the younger group. Spherical aberration was more positive in the older group compared with the younger group. Higher order root mean square increased more rapidly with eccentricity in the older group. Conclusions. Like the axial higher order aberrations, the peripheral higher order aberrations of emmetropes increase with age, particularly coma and spherical aberration.

  • 50.
    Baskaran, Karthikeyan
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Unsbo, Peter
    Biomedical and X-Ray Physics.
    Gustafsson, Jörgen
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för naturvetenskap, NV.
    Influence of age on peripheral ocular aberrations.2011Ingår i: Optometry and Vision Science, ISSN 1040-5488, E-ISSN 1538-9235, Vol. 88, nr 9, s. 1088-1098Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE.: To compare peripheral lower and higher order aberrations across the horizontal (±40°) and inferior (-20°) visual fields in healthy groups of young and old emmetropes. METHODS.: We have measured off-axis aberrations in the groups of 30 younger (24 ± 3 years) and 30 older (58 ± 5 years) emmetropes. The aberrations of OD were measured using the COAS-HD VR Shack-Hartmann aberrometer in 10° steps to ±40° horizontally and -20° inferiorly in the visual field. The aberrations were quantified with Zernike polynomials for a 4 mm pupil diameter. The second-order aberration coefficients were converted to their respective refraction components (M, J45, and J180). Mixed between-within subjects, analysis of variance were used to determine whether there were significant differences in the refraction and aberration components for the between-subjects variable age and the within-subjects variable eccentricity. RESULTS.: Peripheral refraction components were similar in both age groups. Among the higher order coefficients, horizontal coma (C3) and spherical aberration (C4) varied mostly between the groups. Coma increased linearly with eccentricity, at a more rapid rate in the older group than in the younger group. Spherical aberration was more positive in the older group compared with the younger group. Higher order root mean square increased more rapidly with eccentricity in the older group. CONCLUSIONS.: Like the axial higher order aberrations, the peripheral higher order aberrations of emmetropes increase with age, particularly coma and spherical aberration.

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