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  • 1.
    Aguilar, Antonio
    et al.
    Digital Enterprise Research Institute, National University of Ireland, Galway, Ireland.
    van der Putten, Wil
    Department of Medical Physics, University College Hospital Galway, Galway, Ireland .
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Positive Patient Identification using RFID and Wireless  Networks2006In: Proceedings of the HISI 11th Annual Conference and Scientific Symposium, Dublin, Ireland, Dublin, Ireland, 2006Conference paper (Refereed)
    Abstract [en]

    The increased focus on patient safety in hospitals has yielded a flood of new technologies and tools seeking to improve the quality of patient care at the point-of-care. Hospitals are complex institutions by nature, and are constantly challenged to improve the quality of healthcare delivered to patients while trying to reduce the rate of medical errors and improve patient safety. Here a simple mistake such as patient misidentification, specimen misidentification, wrong medication, or wrong blood transfusion can cause the loss of a patient's life. The focus of this paper is the implementation and evaluation of a handheld-based patient identification system that uses radio frequency identification (RFID) and 802.11b wireless networks to identify patients. In this approach, each patient is given a RFID wristband which contains demographic information (patient ID number, patient summary, hospital code) of the patient. A handheld device equipped with 802.11b wireless connectivity and a RFID reader is then used by the medical staff to read the patient's wristband and identify the patient. This work was carried out at the Department of Medical Physics and Bioengineering at the University College Hospital Galway, Ireland and in co-operation with the National University of Ireland, Galway.

  • 2.
    Ahlin, Lars
    et al.
    Swedish Defence Research Agency (FOI).
    Englund, Eva
    FOI.
    Jönsson, Christian
    FOI.
    Söderquist, Ingrid
    FOI.
    Zander, Jens
    KTH, Superseded Departments, Signals, Sensors and Systems.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Automous Tactical Communications Possibilities and Problems1997In: MILCOM 97 Proceedings, 1997, 393-397 p.Conference paper (Refereed)
    Abstract [en]

    In the battlefield of the future, more and more information will be available for making decisions on a tactical level, provided that this information can be dispersed rapidly and accurately. As a consequence, advanced tactical decision support that now is limited to advanced platforms (e.g. combat aircrafts) will become available at a much lower level, ranging from different kinds of vehicles, down to the individual soldier by means of ultra-light weight ``wearable'' equipment.

    Establishing reliable wireless communications in such a large group of users with unprecidented bandwidth demands and requirements on survivability constitutes a considerable enginerring challenge. In the paper we will, after a short review of some existing approaches, investigate the specific engineering challenges and the fundamental limitations of such low level, autonomous communication systems. Further we give an example of a system architecture, harmonized with a proposed structure for third generation commercial wireless systems (e.g. UMTS). Our conclusions show that mainly distributed computing complexity, device power consumption and available bandwidth constitute the fundamental problems.

  • 3. Aitken, Candice L.
    et al.
    Gorniak, Richard J. T.
    New York University.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Farrell, Eward J.
    IBM Research.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Reddy, David P.
    Comparison of three methods used for fusion of SPECT-CT images of liver matastases1998In: Fusion98, International Conference on Multisource-Mulltisensor Information Fusion / [ed] Hamid R. Arabnia and Dongping (Daniel) Zhu, CSREA Press , 1998, 435-442 p.Conference paper (Refereed)
    Abstract [en]

    We compare three methods for fusing SPECT-CT images: ImageMatch - an automatic three-dimensional/two-dimensional method developed by Focus Imaging; IBM Visualization Data Explorer - a three-diemensional interactive method developed by Internation Business Machines, Inc.; and qsh - an interactive three-dimensional/two-dimensional method developed at New York University. While many fusion methods have proved successful for registering brain images, most methods have been less successful for thoracic and abdominal images. We use images of liver metastases obtained with a radiolabeled breast tumor-directed antibody to illustrate the strengths and weakness of the methods reviewed. The images used are typical clinical images from eigth patients. We conclude that an optimal image fusion program should combine the strengths of each of the methods reviewed.

  • 4. Aitken, Candice L.
    et al.
    Mahmoud, Faaiza
    McGuinness, Georgeann
    Kramer, Elissa L.
    Maguire, Gerald Q. Jr.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Noz, Marilyn E.
    New York University.
    Tumor localization and image registration of F-18FDG coincidence detection scans with computed tomographic scans2002In: Clinical Nuclear Medicine, ISSN 0363-9762, E-ISSN 1536-0229, Vol. 27, no 4, 275-282 p.Article in journal (Refereed)
    Abstract [en]

    Purpose: The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management. Methods: F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated. Results: All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%. Conclusions: Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 5.
    Aitken, Candice L.
    et al.
    New York University.
    McGuinness, Georgeann
    New York University.
    Siddiqui, Faaiza
    New York University.
    Ton, Anthony
    New York University.
    Kramer, Elissa L
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Tumor localization and image registration of 18-FDG SPECT scans with CT scans1999In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 40, no 5, 290P-291P p.Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    The aim of this study was to determine the feasibility of registering routine clinical F-18 fluorodeoxyglucose (FDG) coincidence detection (CD) scans with computed tomographic (CT) scans for radiation treatment planning and case management.

    METHODS:

    F-18 FDG CD and chest CT scans, performed in 10 randomly selected patients with confirmed or possible adenocarcinoma of the lung, were evaluated. The quality of the matches was verified by comparisons of the center-to-center distance between a region of interest (ROI) manually drawn on the CT slice and warped onto the CD slice with an ROI drawn manually directly on the CD slice. In addition, the overlap between the two ROIs was calculated.

    RESULTS:

    All 10 F-18 FDG CD and CT scans were registered with good superimposition of soft tissue density on increased radionuclide activity. The center-to-center distance between the ROIs ranged from 0.29 mm to 8.08 mm, with an average center-to-center distance of 3.89 mm +/- 2.42 mm (0.69 pixels +/- 0.34 pixels). The ROI overlap ranged from 77% to 99%, with an average of 90% +/- 5.6%.

    CONCLUSIONS:

    Although the use of F-18 FDG CD shows great promise for the identification of tumors, it shares the same drawbacks as those associated with radiolabeled monoclonal antibody SPECT and ligand-based positron emission tomographic scans in that anatomic markers are limited. This study shows that image registration is feasible and may improve the clinical relevance of CD images.

  • 6.
    Alcala, Yvonne
    et al.
    New York Medical College .
    Olivecrona, Henrik
    Karolinska.
    Olivecrona, Lotta
    Karolinska.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Zeleznik, Michael P.
    Sollerman, Christer
    Sahlgrenska University Hospital, Göteborg, Sweden.
    Qualifying CT for wrist arthroplasty: Extending techniques for total hip arthroplasty to total wrist arthroplasty2005In: Medical Imaging 2005: Image Processing, Pt 1-3 / [ed] Fitzpatrick, JM; Reinhardt, JM, SPIE - The International Sooceity for Optical Engineeering , 2005, Vol. 5747, 1155-1164 p.Conference paper (Refereed)
    Abstract [en]

    The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, I mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

  • 7.
    Anderlind, Eva
    et al.
    KTH, School of Computer Science and Communication (CSC), Human - Computer Interaction, MDI (closed 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, School of Computer Science and Communication (CSC), Numerical Analysis and Computer Science, NADA.
    Lind, Bengt K.
    Karolinska Institute, Department of Medical Radiation Physics.
    Maguire, Gerald Q. Jr.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Will haptic feedback speed up medical imaging? An application to radiation treatment planning2008In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 47, no 1, 32-37 p.Article in journal (Refereed)
    Abstract [en]

    Haptic technology enables us to incorporate the sense of touch into computer applications, providing an additional input/output channel. The purpose of this study was to examine if haptic feedback can help physicians and other practitioners to interact with medical imaging and treatment planning systems. A haptic application for outlining target areas (a key task in radiation therapy treatment planning) was implemented and then evaluated via a controlled experiment with ten subjects. Even though the sample size was small, and the application only a prototype, results showed that haptic feedback can significantly increase (p0.05) the speed of outlining target volumes and organs at risk. No significant differences were found regarding precision or perceived usability. This promising result warrants further development of a full haptic application for this task. Improvements to the usability of the application as well as to the forces generated have been implemented and an experiment with more subjects is planned.

  • 8.
    Anderlind, Eva
    et al.
    KTH, School of Computer Science and Communication (CSC), Human - Computer Interaction, MDI (closed 20111231).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Sallnäs Pysander, Eva-Lotta
    KTH, School of Computer Science and Communication (CSC), Human - Computer Interaction, MDI (closed 20111231).
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Lind, Bengt K.
    Karolinska Institute, Medical Radiation Physics.
    The value of haptic feedback in medical imaging and treatment planning2006In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 81, 1277- p.Article in journal (Refereed)
  • 9.
    Baxter, Brent S.
    et al.
    University of Utah.
    Hitchner, Lewis E.
    University of Utah.
    Maguire Jr., Gerald Q.
    Columbia University.
    A standard format for digital image exchange1982Book (Other academic)
  • 10.
    Baxter, Brent S.
    et al.
    University of Utah.
    Hitchner, Lewis E.
    University of Utah.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Characteristics of a Protocol for Exchanging Digital Image-information1982In: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 318, 273-277 p.Article in journal (Refereed)
  • 11.
    Baxter, Brent S.
    et al.
    University of Utah.
    Zeleznik, Michael P.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    What Types of Standards would be useful in PACS Activities1983In: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 418, 146-150 p.Article in journal (Refereed)
  • 12.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Harper, B.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Judge, J.
    Location Aware Mobile Computing1997In: Proceedings of ICT '97, IEEE , 1997, 1319-1324 p.Conference paper (Refereed)
  • 13.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Smith, Mark T.
    Location Augmented Mobile Computing and Communication Systems1997In: Proc. Third Asia-Pacific Conference on Communications (APCC’97), 1997, 827-831 p.Conference paper (Refereed)
  • 14.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Smith, Mark T.
    Location Based Personal Mobile Computing and Communication1998In: Proceedings of 9th IEEE Workshop on Local and Metropolitan Area Networks, IEEE , 1998, 23-24 p.Conference paper (Refereed)
  • 15.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Smith, Mark T.
    Using location and environment awareness in mobile communications1997In: Proceedings of the International Conference on Information, Communications and Signal Processing, ICICS, IEEE , 1997, 1781-1785 p.Conference paper (Refereed)
    Abstract [en]

    We are investigating the use of badge based wearable computers to create highly mobile location and environment aware systems. When coupled to intelligent servers the badges provide an unparalleled platform for human centred information environments. This paper describes the architecture of the badge, its distributed computing environment, and presents initial results of application development trials conducted by a class of telecommunications students at KTH.

  • 16.
    Biema, Michael K. van
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Lerner, Mark D.
    Columbia University.
    Stolfo, Salvatore J.
    Columbia University.
    The Design and Implementation of System Level Language for the DADO Parallel Machine1987In: Proceedings of the Twentieth Annual Hawaii International Conference on System Sciences 1987. Volume 3: Healthcare Systems, Special Topics, IEEE and ACM , 1987, 152-162 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we describe necessary criteria for the design of parallel system level languages and their support environment. We base the criteria on our own experiences in building a system level language parallel PSL (Parallel Portable Standard Lisp) for the DADO machine developed at Columbia University. The DADO machine is a special purpose massively parallel binary tree structured architecture. We describe the process of language design and implementation on a 1023 node prototype machine. After generalizing what we have learned from this specific implementation to the generic task of building a system level language for a parallel machine, we conclude with a discussion of desirable characteristics such a language should have to allow the easy transition from a language with explicit parallelism to one where the parallelism is implicit.

  • 17.
    Biema, Michael K. van
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Stolfo, Salvatore J.
    Columbia University.
    The constraint-based paradigm: integrating object-oriented and rule-based programming1990In: Proceedings of the Twenty-Third Annual Hawaii International Conference on System Sciences. Volume 1: Architecture Track, IEEE Computer Society, 1990, Vol. ii, 358-366 p.Conference paper (Refereed)
    Abstract [en]

    The authors introduce a novel formalism that combines the object-oriented and rule-based paradigms in an elegant and orthogonal way. The constraint-based model is a generalization of traditional object-oriented paradigms and is based on three orthogonal subparadigms. The first is constraint-based invocation, which is a generalization of the traditional invocation where dispatch is done based on the types of the arguments. In constraint-based invocation, dispatch is done based on constraints that are arbitrary user-defined predicates. The second subparadigm is instance inheritance, a dual to the concept of class inheritance in the sense that class inheritance structures classes and instance inheritance structures instances. The third is procedural attachments (also known as active values or access-oriented programming), where a function is called in a data-driven manner. The semantics of this concept are generalized to all objects in the constraint-based model. A central philosophical argument is that so-called multiparadigm languages should be developed not by combination of paradigms in a partially integrated system, but by their synergistic unification under a new, subsuming paradigm.

  • 18.
    Birnbaum, Bernard A.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University.
    Chapnick, Jeffrey V.
    New York University.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Weinreb, Jeffrey C.
    New York University.
    Kaminer, Evan M.
    New York University.
    Kramer, Elissa L.
    New York University.
    Hepatic hemangiomas: diagnosis with fusion of MR, CT, and Tc-99m-labeled red blood cell SPECT images1991In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 181, no 2, 469-474 p.Article in journal (Refereed)
    Abstract [en]

    A method of image analysis was developed for correlation of hemangiomas detected at computed tomography {(CT)} and/or magnetic resonance {(MR)} imaging with increased blood pool activity evident at single photon emission {CT} {(SPECT)} performed after labeling of red blood cells with technetium-99m. Image analysis was performed in 20 patients with 35 known hepatic hemangiomas. After section thickness and pixel sizes of the different studies were matched, intrinsic landmarks were chosen to identify anatomically corresponding locations. Regions of interest {(ROIs)} drawn on the {CT} and/or {MR} images were translated, rotated, and reprojected to match the areas of interest on the corresponding {SPECT} images by means of a two-dimensional polynomial-based warping algorithm. Analysis of {ROIs} on 30 {SPECT-MR} and 20 {SPECT-CT} pairs of registered images provided absolute confirmation that 34 suspected hemangiomas identified on {SPECT} images correlated exactly with lesions seen on {CT} and/or {MR} images. Accuracy of fusion was within an average of 1.5 pixels +/- 0.8 (+/- 1 standard deviation). The technique enabled diagnostic confirmation of hemangiomas as small as 1.0 cm and proved useful for evaluating lesions located adjacent to intrahepatic vessels.

  • 19.
    Birnbaum, Bernard A.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Chapnick, Jeffrey V
    New York University.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Weinreb, Jeffrey C.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Clinical Evaluation of Image Fusion Using MR Imaging, CT, and SPECT-RBC Images of Hepatic Hemangiomas1990In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, P228- p.Article in journal (Refereed)
  • 20.
    Bogdanov, Kirill
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Network Systems Laboratory (NS Lab).
    Peón-Quirós, Miguel
    Complutense University of Madrid.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Kostic, Dejan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Network Systems Laboratory (NS Lab).
    The Nearest Replica Can Be Farther Than You Think2015In: Proceedings of the ACM Symposium on Cloud Computing 2015, Association for Computing Machinery (ACM), 2015, 16-29 p.Conference paper (Refereed)
    Abstract [en]

    Modern distributed systems are geo-distributed for reasons of increased performance, reliability, and survivability. At the heart of many such systems, e.g., the widely used Cassandra and MongoDB data stores, is an algorithm for choosing a closest set of replicas to service a client request. Suboptimal replica choices due to dynamically changing network conditions result in reduced performance as a result of increased response latency. We present GeoPerf, a tool that tries to automate the process of systematically testing the performance of replica selection algorithms for geodistributed storage systems. Our key idea is to combine symbolic execution and lightweight modeling to generate a set of inputs that can expose weaknesses in replica selection. As part of our evaluation, we analyzed network round trip times between geographically distributed Amazon EC2 regions, and showed a significant number of daily changes in nearestK replica orders. We tested Cassandra and MongoDB using our tool, and found bugs in each of these systems. Finally, we use our collected Amazon EC2 latency traces to quantify the time lost due to these bugs. For example due to the bug in Cassandra, the median wasted time for 10% of all requests is above 50 ms.

  • 21.
    Bogdanov, Kirill
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Network Systems Laboratory (NS Lab).
    Peón-Quirós, Miguel
    Complutense University of Madrid.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Kostić, Dejan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Network Systems Laboratory (NS Lab).
    Toward Automated Testing of Geo-Distributed Replica Selection Algorithms2015In: Proceedings of the 2015 ACM Conference on Special Interest Group on Data Communication, Association for Computing Machinery (ACM), 2015, 89-90 p.Conference paper (Refereed)
    Abstract [en]

    Many geo-distributed systems rely on a replica selection algorithms to communicate with the closest set of replicas.  Unfortunately, the bursty nature of the Internet traffic and ever changing network conditions present a problem in identifying the best choices of replicas. Suboptimal replica choices result in increased response latency and reduced system performance. In this work we present GeoPerf, a tool that tries to automate testing of geo-distributed replica selection algorithms. We used GeoPerf to test Cassandra and MongoDB, two popular data stores, and found bugs in each of these systems.

  • 22.
    Brodén, Cyrus
    et al.
    Department of Molecular Medicine and Surgery, Karolinska Institutet.
    Olivecrona, Henrik
    Department of Molecular Medicine and Surgery, Karolinska Institutet.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    School of Computing, College of Engineering, University of Utah.
    Sköldenberg, Olof
    Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet.
    Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study2016In: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, 5909741Article in journal (Refereed)
    Abstract [en]

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty.

    Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated.

    Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv.

    Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting.

  • 23.
    Brown, Lisa G.
    et al.
    IBM Thomas J. Watson Research Center and Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Landmark-based 3D fusion of SPECT and CT images1993In: Sensor fusion VI: 7-8 September 1993, Boston, Massachusetts / [ed] Paul S. Schenker, SPIE - International Society for Optical Engineering, 1993, Vol. 2059, 166-174 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we present interactive visualization procedures for registration of SPECT and CT images based on landmarks. Because of the poor anatomic detail available in many SPECT images, registration of SPECT images with other modalities often requires the use of external markers. These markers may correspond to anatomic structures identifiable in the other modality image. In this work, we present a method to nonrigidly register SPECT and CT images based on automatic marker localization and interactive anatomic localization using 3D surface renderings of skin. The images are registered in 3D by fitting low order polynomials which are constrained to be near rigid. The method developed here exploits 3D information to attain greater accuracy and reduces the amount of time needed for expert interaction.

  • 24.
    Chandra, Ramesh
    et al.
    New York University.
    Lo, S.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Absorbed Fractions for Radionuclides Uniformly Distributed in the Myocardium1976In: Proceedings of the Radiopharmaceutical Dosimetry Symposium, Rockville, MD, USA: HEW Radiopharmaceutical Dosimetry Symposium , 1976, 199-207 p.Conference paper (Refereed)
  • 25.
    Chapnick, J. V.
    et al.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Kramer, Elissa L.
    New York University.
    Sanger, J. J.
    New York University.
    Birnbaum, B.A.
    New York University.
    Megibow, A.J.
    Techniques for multimodality image registration1993In: Bioengineering, Proceedings of the Northeast Conference, 1993, 221-222 p.Conference paper (Refereed)
    Abstract [en]

    The authors describe the development of techniques used for cross-modality correlation of medical images. To accomplish this goal, software routines were developed which automate and standardize the comparison of images within and between three-dimensional tomographic imaging modalities. Data from phantoms and clinical studies reflect the success of this technique.

  • 26.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Sanger, Joseph J.
    New York University.
    Birnbaum, Bernard A.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Megibow, Alec J.
    New York University.
    Oratz, R.
    New York University, Department of Radiology.
    Weinreb, Jeffrey C.
    New York University.
    Martino, J.
    New York University.
    Structural, Functional Image Fusion in Cancer Patients1990In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, P377- p.Article in journal (Refereed)
  • 27.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Oratz, R.
    New York University.
    Birnbaum, Bernard A.
    New York University.
    Martino, J.
    New York University.
    Fusion of Functional and Structural Images1990In: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 177, P223- p.Article in journal (Refereed)
  • 28.
    Chapnick, Jeffrey V
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Sanger, Joseph J.
    New York University.
    Megibow, Alec J.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Oratz, R.
    New York University, Department of Radiology.
    Birnbaum, Bernard A.
    New York University.
    Martino, J.
    New York University, Department of Radiology.
    Fusion of Functional Spect Images with Structural CT/MRI Images1991In: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 32, 1135- p.Article in journal (Refereed)
  • 29.
    Crafoord, Joakim
    et al.
    Karolinska Hospital, Department of Radiology.
    Mahmoud, Faaiza
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    RAHD Oncology Products, St. Lois, MO, USA.
    Comparison of two landmark based image registration methods for use with a body atlas2000In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 16, no 2, 75-82 p.Article in journal (Refereed)
    Abstract [en]

    We describe preliminary work registering abdominal MRI images from three healthy male volunteers. Anatomically selected 3D homologous point pairs (landmarks), from which eigenvalues were generated to form the basis for a 3D non-affine polynomial transformation, were placed on axial slices alone and on axial, coronal and sagittal slices. Registration accuracy was judged visually by comparing superimposed 3D isosurfaces from the reference, untransformed, and transformed volume data and by comparing merged 2D slices projected fi om the transformed and reference volume data superimposed with 2D isolines. The squared sum of intensity differences between the transformed/untransformed and the reference volume was significant at the 0.05 (p >0.05) confidence level. The correlation coefficient improved by an average of 38% and the cross correlation between pixel values improved by an average of 22%. In each trial, the standard deviation of the landmarks after transformation was within one voxel and the standard error of the mean was not significantly different from zero at the 0.05 confidence level. Abdominal isosurface volume differences (between individuals) changed from an average of 14.5% before registration to 2.9% after registration. This experiment shows that it is possible to choose landmarks such that abdominal data from different subject volumes can be mapped to a common reference, and thus that it is possible to use this combined volume both to form an atlas and to warp abdominal data from an atlas to a patient volume.

  • 30.
    Dewyngaert, J. Keith
    et al.
    New York University.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Ellerin, B.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Zeleznik, Michael P.
    RAHD Oncology Products, St. Louis, MO, USA.
    Procedure for unmasking localization information from ProstaScint scans for prostate radiation therapy treatment planning2004In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, Vol. 60, no 2, 654-662 p.Article in journal (Refereed)
    Abstract [en]

    Purpose: To demonstrate a method to extract the meaningful biologic information from In-111-radiolabeled capromab pendetide (ProstaScint) SPECT scans for use in radiation therapy treatment planning by removing that component of the In-111 SPECT images associated with normal structures. Methods and Materials: We examined 20 of more than 80 patients who underwent simultaneous Tc-99m/In-111 SPECT scans, which were subsequently registered to the corresponding CT/MRI scans. A thresholding algorithm was used to identify Tc-99m uptake associated with blood vessels and CT electron density associated with bone marrow. Corresponding voxels were removed from the In-111 image set. Results: No single threshold value was found to be associated with the Tc-99m uptake that corresponded to the blood vessels. Intensity values were normalized to a global maximum and, as such, were dependent upon the quantity of Tc-99m pooled in the bladder. The reduced ProstaScint volume sets were segmented by use of a thresholding feature of the planning system and superimposed on the CT/MRI scans. Conclusions: ProstaScint images are now closer to becoming a biologically and therapeutically useful and accurate image set. After known sources of normal intensity are stripped away, the remaining areas that demonstrate uptake may be segmented and superimposed on the treatment-planning CT/MRI volume.

  • 31.
    Duchamp, Daniel J.
    et al.
    Columbia University, Department of Computer Science.
    Feiner, Steven K.
    Columbia University, Department of Computer Science.
    Kaiser, Gail E.
    Columbia University, Department of Computer Science.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Integration of Knowledge Bases into an Environment of Portable Electronic Notebooks1990Report (Other academic)
  • 32.
    Duchamp, Daniel J.
    et al.
    Columbia University.
    Feiner, Steven K.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Software technology for wireless mobile computing1991In: IEEE Network, ISSN 0890-8044, Vol. 5, no 6, 12-18 p.Article in journal (Refereed)
    Abstract [en]

    Some of the possibilities and requirements for mobile computing on wireless local area networks (LANs) are discussed from the systems software viewpoint. The design of the Student Electronic Notebook (SEN) is sketched to provide a partial catalog of problems in building a real system for wireless mobile computing. This project was initiated to investigate the potential of wireless mobile computing to reshape education. Some of the key directions for research in software technology for wireless, mobile computing are examined. Some of the authors' experience with wireless LANs is related.

  • 33.
    Eisenstadter, Yoram
    et al.
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Exploiting Locality of Reference in MIMD Parallel Symbolic Computation1987In: Proceedings of the International Conference on Parallel Processing, IEEE, Pennsylvania State Univ. Press , 1987, 742-744 p.Conference paper (Refereed)
  • 34.
    Erdman, William A.
    et al.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Stahl, T. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    A Picture Archiving and Communication System - Modus Operandi for a Filmless Nuclear Medicine Department1986In: Administrative Radiology, ISSN 0738-6974, Vol. 5, no 1, 34-38 p.Article in journal (Refereed)
  • 35.
    Erdman, William A.
    et al.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Stahl, T. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Tokarz, R. J.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University.
    Development of a Digital Nuclear-Medicine System1983In: Proceedings of the Society of Photo-Optical Instrumentation Engineers, ISSN 0361-0748, Vol. 418, 100-102 p.Article in journal (Refereed)
  • 36.
    Ericson, Anne
    et al.
    Karolinska Institute, Department of Molecular Medicine and Surgery, Section of Orthopaedics and Sports Medicine.
    Arndt, Anton
    Karolinska Institut, Department of Clinical Science, Intervention and Technology, Section of Orthopaedics.
    Stark, Andreas
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Olivecrona, Henrik
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Fusion of radio stereometric analysis data into computed tomography space: Application to the elbow joint2007In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 40, no 2, 296-304 p.Article in journal (Refereed)
    Abstract [en]

    Improvement of joint prostheses is dependent upon information concerning the biomechanical properties of the joint. Radiostereometric analysis (RSA) and electromagnetic techniques have been applied in previous cadaver and in vivo studies on the elbow joint to provide valuable information concerning joint motion axes. However, such information is limited to mathematically calculated positions of the axes according to an orthogonal coordinate system and is difficult to relate to individual skeletal anatomy. The aim of this study was to evaluate the in vivo application of a new fusion method to provide three-dimensional (31)) visualization of flexion axes according to bony landmarks. In vivo RSA data of the elbow joint's flexion axes was combined with data obtained by 3D computed tomography (CT). Results were obtained from five healthy subjects after one was excluded due to an instable RSA marker. The median error between imported and transformed RSA marker coordinates and those obtained in the CT volume was 0.22mm. Median maximal rotation error after transformation of the rigid RSA body to the CT volume was 0.003 degrees. Points of interception with a plane calculated in the RSA orthogonal coordinate system were imported into the CT volume, facilitating the 3D visualization of the flexion axes. This study demonstrates a successful fusion of RSA and CT data, without significant loss of RSA accuracy. The method could be used for relating individual motion axes to a 3D representation of relevant joint anatomy, thus providing important information for clinical applications such as the development of joint prostheses.

  • 37.
    Ericson, Anne
    et al.
    Karolinska Institute, Department of Molecular Medicine and Surgery, Section of Orthopaedics and Sports Medicine.
    Olivecrona, Henrik
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Stark, Andreas
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Arndt, Anton
    Karolinska Institut, Department of Clinical Science, Intervention and Technology, Section of Orthopaedics.
    Computed tomography analysis of radiostereometric data to determine flexion axes after total joint replacement: Application to the elbow joint2010In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 43, no 10, 1947-1952 p.Article in journal (Refereed)
    Abstract [en]

    Kinematic analysis for in vivo assessment of elbow endoprostheses requires knowledge of the exact positions of motion axes relative to bony landmarks or the prosthesis. A prosthesis-based reference system is required for comparison between individuals and studies. The primary aim of this study was to further develop an earlier described algorithm for fusion of radiostereometric analysis (RSA) data and data obtained in 3D computed tomography (CT) for application to the elbow after total joint replacement. The secondary aim was to propose a method for marking of prostheses in 3D CT, enabling definition of a prosthesis-based reference system. Six patients with elbow endoprostheses were investigated. The fusion of data made it possible to visualize the motion axes in relation to the prostheses in the 3D CT volume. The differences between two repeated positioning repetitions of the longitudinal prosthesis axis were less than 0.6 degrees in the frontal and sagittal planes. Corresponding values for the transverse axis were less than 0.6 degrees in the frontal and less than 1.4 degrees (in four out of six less than 0.6 degrees) in the horizontal plane. This study shows that by fusion of CT and RSA data it is possible to determine the accurate position of the flexion axes of the elbow joint after total joint replacement in vivo. The proposed method for implant marking and registration of reference axes enables comparison of prosthesis function between patients and studies.

  • 38.
    Escudero-Pascual, Alberto
    et al.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Wireless at KTH. KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Role(s) of a proxy in location based services2002In: 13TH IEEE INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS, VOL 1-5, PROCEEDINGS: SAILING THE WAVES OF THE WIRELESS OCEANS, IEEE , 2002, 1252-1256 p.Conference paper (Refereed)
    Abstract [en]

    We examine a number of roles that a proxy server can play in location based services and how it can be used to provide protection of personal identifiable information. Location data, service requests, and privacy policies are encoded in XML by the mobile terminal and forwarded to a proxy server placed between the mobile terminal and the location based service(s). By a suitable architecture in the mobile terminal and in the proxy, we can hide the mobile device's network location, hide the identity of its user, and, in some cases, provide misleading physical location(s). We have applied our privacy model to location information obtained from a GPS receiver. The GPS-based method was chosen as being the only available method where the positioning calculation function (PCF) is fully under the user's control, since the position is calculated within the mobile terminal; other technologies rely on the network infrastructure, and hence some or all of the position data is outside the user's control. A proof of concept was implemented using Fastrax's iTrax02 small, ultra-low power consumption GPS receiver. We illustrate a number of different functions which can be provided by examining some scenarios.

  • 39.
    Farrell, Edward J.
    et al.
    IBM Research.
    Gorniak, Richard J.
    New York University.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Reddy, David P.
    Graphical 3D medical image registration and quantification1997In: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 21, no 3, 155-172 p.Article in journal (Refereed)
    Abstract [en]

    We present a graphical three-dimensional method that facilitates image registration and fusion, and provides quantitative geometric and volume information. In particular it enhances the use of functional (radiopharmaceutical) imaging {(SPECT}, {PET)} which, though a powerful clinical tool, has the disadvantage of low spatial resolution and ill-defined boundaries. Registration between functional images and structural images {(MRI}, {CT)} can augment the anatomical context of these functional images.

  • 40.
    Farrell, Edward J.
    et al.
    IBM Thomas J. Watson Research Center.
    Kramer, Elissa L.
    New York University.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Quantitative 3D visualization in nuclear medicine1995In: Proceedings of the SPIE Medical Imaging 1995, SPIE - International Society for Optical Engineering, 1995, Vol. 2431, 54-64 p.Conference paper (Refereed)
    Abstract [en]

    SPECT is a powerful clinical tool. However, the low spatial resolution and ill-defined boundaries associated with SPECT require special consideration in visualization. Quantitative geometric and magnitude information are areas of particular usefulness in evaluating disease states. In this paper, we describe a set of practical 3D visualization tools to display and analyze SPECT data, and present interactive methods to measure (1) the relative position, size and shape of regions of interest and (2) the magnitude and distribution of radioactive count information. Interactive pick tools allow users to extract values at selected points, distance between points, or value profiles along selected line segments. In the three-dimensional reconstruction, transparent and opaque isosurfaces are formed simultaneously at specified activity levels, and the volume enclosed by the opaque surface is displayed. The utility of these tools is demonstrated with two types of patient studies: those using tumor-avid agents to identify active tumor in the chest and abdomen, and those used for evaluating the volume of perfused myocardium.

  • 41.
    Galvin, J. M.
    et al.
    New York University.
    Han, K.
    Noz, Marilyn E.
    New York University.
    Vaccaro, T.
    Cooper, J.
    New York University.
    Reddy, David P.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Teleinformatics.
    Warping CT scans from nontreatment to treatment position1997In: Radiation oncology investigations (Print), ISSN 1065-7541, E-ISSN 1520-6823, Vol. 5, no 4, 206-212 p.Article in journal (Refereed)
    Abstract [en]

    This paper describes a cost-effective technique that optimally utilizes all available diagnostic studies for three-dimensional treatment planning. A simulator unit modified to produce cross-sectional images {(simulator-CT} unit) is used to create a reference data set with the patient in the treatment position. Registration software (qsh) brings other diagnostic studies into agreement with this reference data set. Two cases are presented as examples of the use of this technique. Registration of abdominal scans from the same patient demonstrates the warping of a nontreatment position study to the treatment position. The second case is based on paired data sets through the head, in which the diagnostic study was obtained by using a gantry tilt to follow the base of the skull and to avoid sections passing through the teeth. The registration software provides a method for combining diagnostic studies into a single "master" data set. The success of the transformation depends on the operator's ability to identify corresponding anatomic landmarks for different data sets and on the magnitude of the variation in the patient's position from one procedure to the next. Limitations in image quality and the number of cross-sections obtainable from a {simulator-CT} unit can be partially overcome by using the described technique. Thus, the information contained in nontreatment position diagnostic tests can be used accurately for treatment planning at limited cost.

  • 42.
    Goldvasser, Dov
    et al.
    Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston MA, United States .
    Hansen, Viktor J.
    Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston MA, United States .
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Zeleznik, Michael P.
    University of Utah, Salt Lake City, UT, USA.
    Olivecrona, Henrik
    Karolinska Institute.
    Bragdon, Charles R.
    Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston MA, United States .
    Weidenhielm, Lars
    Karolinska Institute.
    Malchau, Henrik
    Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston MA, United States .
    In vivo and ex vivo measurement of polyethylene wear in total hip arthroplasty2014In: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 85, no 3, 271-275 p.Article in journal (Refereed)
    Abstract [en]

    Background - Determination of the amount of wear in a polyethylene liner following total hip arthroplasty (THA) is important for both the clinical care of individual patients and the development of new types of liners. Patients and methods - We measured in vivo wear of the polyethylene liner using computed tomography (CT) (obtained in the course of regular clinical care) and compared it to coordinate-measuring machine (CMM) readings. Also, changes in liner thickness of the same retrieved polyethylene liner were measured using a micrometer, and were compared to CT and CMM measurements. The distance between the centers of the acetabular cup and femoral head component was measured in 3D CT, using a semi-automatic analysis method. CMM readings were performed on each acetabular liner and data were analyzed using 3D computer-aided design software. Micrometer readings compared the thickest and thinnest regions of the liner. We analyzed 10 THA CTs and retrievals that met minimal requirements for CT slice thickness and explanted cup condition. Results - For the 10 cups, the mean difference between the CT readings and the CMM readings was -0.09 (-0.38 to 0.20) mm. This difference was not statistically significant (p = 0.6). Between CT and micrometer, the mean difference was 0.11 (-0.33 to 0.55) mm. This difference was not statistically significant (p = 0.6). Interpretation - Our results show that CT imaging is ready to be used as a tool in clinical wear measurement of polyethylene liners used in THA.

  • 43.
    Goldvasser, Dov
    et al.
    Massachusetts General Hospital, Boston MA, USA.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire, Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    Olivecrona, Henrik
    Karolinska Institutet, Sweden.
    Bragdon, Charles R.
    Massachusetts General Hospital, Boston MA, USA.
    Malchau, Henrik
    Massachusetts General Hospital, Boston MA, USA.
    A New Technique for Measuring Wear in Total Hip Arthroplasty Using Computed Tomography2012In: The Journal of Arthroplasty, ISSN 0883-5403, E-ISSN 1532-8406, Vol. 27, no 9, 1636-1640 p.Article in journal (Refereed)
    Abstract [en]

    Accurately estimating polyethylene wear in 3 dimensions, without the need for additional procedures or equipment, is of significant interest. We investigated the use of a high-resolution clinical computed tomographic (CT) scanner to estimate femoral head displacement relative to the cup as an indirect method of estimating polyethylene wear. A hip phantom was used to simulate the 3-dimensional displacement of a femoral head. The phantom was imaged in a high-resolution CT scanner. The mean difference between the true phantom displacement as positioned by micrometers and the calculated displacement based on the CT images was as follows: for the x-axis, 0 mm (SD, 0.213; SE, 0.058); y-axis, 0.039 mm (SD, 0.035; SE, 0.026); and z-axis, 0.039 mm (SD, 0.051; SE, 0.020).

  • 44. Gorniak, R. J. T.
    et al.
    Kramer, E. L.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Superseded Departments, Microelectronics and Information Technology, IMIT.
    Noz, Marilyn E.
    New York University.
    Schettino, C. J.
    Zeleznik, Michael P.
    Evaluation of a semiautomatic 3D fusion technique applied to molecular imaging and MRI brain/frame volume data sets2003In: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 27, no 2, 141-156 p.Article in journal (Refereed)
    Abstract [en]

    A generally applicable {3D} fusion method was evaluated using molecular imaging and {MRI} volumetric data sets from 15 brain tumor patients with stereotactic frames attached to their skull. Point pairs, placed on the frame only, were chosen, polynomial warping coefficients were generated to map voxels from one coordinate space to the other. The {MRI} frame was considered the reference structure and the standard for "correct" registration. An {ANOVA} test (p {\textgreater} 0.05) confirmed the point pair choice to be consistent. The 95\% confidence interval for the t-test showed the measured distance difference between the registered volumes was within one {MRI} voxel. A further experiment was conducted to independently evaluate the brain registration based on testing for consistency of randomly selected interior/exterior points. A t-test result (p {\textless} 0.05) showed that the consistency (i.e., both interior or both exterior) before and after volume registration were significantly different. This fusion method may be a viable alternative when other methods fail.

  • 45.
    Gorniak, Richard J.
    et al.
    New York University.
    Farrell, Edward J.
    IBM Thomas J. Watson Research Center.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Reddy, David P.
    Accuracy of an Interactive Registration Technique Applied to Thallium-201 SPECT and MR Brain Images1997In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 24, no 8, 1354- p.Article in journal (Refereed)
  • 46.
    Gorniak, Richard J.
    et al.
    New York University.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Schettino, C. J.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Evaluation of a Semi-Automatic 3D Fusion Technique Applied to Thallium-201 SPECT and MRI Brain/Frame Volume Data Sets2001In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 28, no 8, 1190- p.Article in journal (Refereed)
  • 47.
    Griss, Martin L.
    et al.
    University of Utah, Department of Computer Science.
    Benson, Eric
    University of Utah, Department of Computer Science.
    Kessler, Robert R.
    University of Utah, Department of Computer Science.
    Lowder, Steve
    University of Utah, Department of Computer Science.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Peterson, John W.
    University of Utah, Department of Computer Science.
    PSL Implementation Guide1982Report (Other academic)
  • 48.
    Griss, Martin L.
    et al.
    University of Utah.
    Benson, Eric
    University of Utah.
    Maguire Jr., Gerald Q.
    University of Utah.
    PSL: A Portable LISP System1982In: Proceedings of the 1982 ACM symposium on LISP and functional programming - LFP ’82, 1982, 88-97 p.Conference paper (Other academic)
    Abstract [en]

    This paper presents the implementation strategy and current status of a new Portable LISP System, PSL, based upon STANDARD LISP. PSL is written entirely in itself and is compiled with an efficient LISP compiler with machine-oriented optirnizations. A full PSL is currently running on a DECSystem-20 and a VAX, and a preliminary version runs on a Motorola MC68000. Versions for a CRAY-1 and an IBM-370 are planned.

  • 49.
    Griss, Martin L.
    et al.
    University of Utah, Department of Computer Science.
    Hearn, Anthony C.
    University of Utah, Department of Computer Science.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Using The MODE Analyzing version of REDUCE1980Report (Other academic)
  • 50.
    Griss, Martin L.
    et al.
    University of Utah, Department of Computer Science.
    Kessler, Robert R.
    University of Utah, Department of Computer Science.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    TLISP - A Transportable LISP Implemented in Pcode1979Report (Other academic)
1234567 1 - 50 of 302
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