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  • 201.
    Mahmoud, Faaiza
    et al.
    New York University.
    Ton, Anthony
    New York University.
    Crafoord, Joakim
    Department of Radiology, Karolinska Hospital.
    Kramer, Elissa L.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Noz, Marilyn E.
    New York University.
    Zeleznik, Michael P.
    Comparison of Three Image Methods for Registration of Abdominal/Pelvic Volume Data Sets from Functional-Anatomic Scans2000Inngår i: Visualization Development Environments 2000, Princeton Plasma Physics Laboratory , 2000, s. 180-187Konferansepaper (Fagfellevurdert)
  • 202.
    Mahmoud, Faaiza
    et al.
    New York University.
    Ton, Anthony
    New York University.
    Crafoord, Joakim
    Department of Radiology, Karolinska Hospital.
    Kramer, Elissa L.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Noz, Marilyn E.
    New York University.
    Zeleznik, Michael P.
    Comparison of three methods for registration of abdominal/pelvic volume data sets from functional-anatomic scans2000Inngår i: SPIE - The International Society for Optical Engineering, SPIE - International Society for Optical Engineering, 2000, Vol. 3979, s. 1378-1386Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this work was to evaluate three volumetric registration methods in terms of technique, user-friendliness and time requirements. CT and SPECT data from 11 patients were interactively registered using: a 3D method involving only affine transformation; a mixed 3D - 2D non-affine (warping) method; and a 3D non-affine (warping) method. In the first method representative isosurfaces are generated from the anatomical images. Registration proceeds through translation, rotation, and scaling in all three space variables. Resulting isosurfaces are fused and quantitative measurements are possible. In the second method, the 3D volumes are rendered co-planar by performing an oblique projection. Corresponding landmark pairs are chosen on matching axial slice sets. A polynomial warp is then applied. This method has undergone extensive validation and was used to evaluate the results. The third method employs visualization tools. The data model allows images to be localized within two separate volumes. Landmarks are chosen on separate slices. Polynomial warping coefficients are generated and data points from one volume are moved to the corresponding new positions. The two landmark methods were the least time consuming (10 to 30 minutes from start to finish), but did demand a good knowledge of anatomy. The affine method was tedious and required a fair understanding of 3D geometry.

  • 203. Marsh, Ian
    et al.
    Severiano, Juan Carlos Martín
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    Nunes, Victor
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Telekommunikationssystem, TSLab (stängd 2012-01-01).
    Maguire, Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Mikroelektronik och Informationsteknik, IMIT.
    IEEE 802.11b voice quality assessment using crosslayer information.2006Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper reports on the suitability of IEEE802.11b networks for carrying real-time voice traffic, considering particularly the end terminals. More specifically we looked at such networks in different operating circumstances:an outdoor environment, an office environment,and the influence of competing traffic. Additionally wehave investigated the link protocol in combination with theapplication layer. Based on over 2500 recorded sessions,it can be generally concluded that the 802.11b protocolcan support real-time voice; particularly if the link transmissionrate is immediately lowered after an unsuccessful initial transmission. However, we did find situations where the voice quality deteriorated below commonly accepted values, such as when competing with high-rate TCP traffic,when intervening obstacles blocked the transmission path,and with certain uses of the RTS/CTS mechanism.

  • 204. McGee, Ellen M.
    et al.
    Maguire, Gerald Q. Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Becoming borg to become immortal: Regulating brain implant technologies2007Inngår i: Cambridge Quarterly of Healthcare Ethics, ISSN 0963-1801, E-ISSN 1469-2147, Vol. 16, nr 3, s. 291-302Artikkel i tidsskrift (Fagfellevurdert)
  • 205.
    McGee, Ellen M.
    et al.
    Long Island University - C. W. Post, Long Island Center for Ethics.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Ethical Assessment of Implantable Brain Chips1998Inngår i: The Proceeedings of the Twentieth World Congress of Philosophy, 1998Konferansepaper (Fagfellevurdert)
    Abstract [en]

    My purpose is to initiate a discussion of the ethics of implanting computer chips in the brain and to raise some initial ethical and social questions. Computer scientists predict that within the next twenty years neural interfaces will be designed that will not only increase the dynamic range of senses, but will also enhance memory and enable "cyberthink" — invisible communication with others. This technology will facilitate consistent and constant access to information when and where it is needed. The ethical evaluation in this paper focuses on issues of safely and informed consent, issues of manufacturing and scientific responsibility, anxieties about the psychological impacts of enhancing human nature, worries about possible usage in children, and most troubling, issues of privacy and autonomy. Inasmuch as this technology is fraught with perilous implications for radically changing human nature, for invasions of privacy and for governmental control of individuals, public discussion of its benefits and burdens should be initiated, and policy decisions should be made as to whether its development should be proscribed or regulated, rather than left to happenstance, experts and the vagaries of the commercial market.

  • 206.
    McGee, Ellen M.
    et al.
    Long Island University - C. W. Post, Long Island Center for Ethics.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Implantable brain chips: ethical and policy issues2001Inngår i: Medical ethics (Burlington, Mass.), ISSN 1543-4672, s. 1-2, 8Artikkel i tidsskrift (Fagfellevurdert)
  • 207.
    Mills, Russell C.
    et al.
    Columbia University, Department of Computer Sceince.
    Radouch, Zdenek
    Columbia University, Department of Computer Sceince.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Sceince.
    A New Kernel for the DADO2 Parallel Computer1987Rapport (Annet vitenskapelig)
  • 208.
    Mills, Russell C.
    et al.
    Columbia University.
    Woodbury, Leland
    Columbia University.
    Maguire Jr., Gerald Q.
    Columbia University.
    A Debugging Environment for the DADO Parallel Computer1988Inngår i: Proceedings of Third International Conference on Supercomputing, International Supercomputing Institute Incorporated , 1988, s. 413-421Konferansepaper (Fagfellevurdert)
  • 209.
    Mitola III, Joseph
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Cognitive radio: making software radios more personal1999Inngår i: IEEE personal communications, ISSN 1070-9916, E-ISSN 1558-0652, Vol. 6, nr 4, s. 13-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Software radios are emerging as platforms for multiband multimode personal communications systems. Radio etiquette is the set of RF bands, air interfaces, protocols, and spatial and temporal patterns that moderate the use of the radio spectrum. Cognitive radio extends the software radio with radio-domain model-based reasoning about such etiquettes. Cognitive radio enhances the flexibility of personal services through a radio knowledge representation language. This language represents knowledge of radio etiquette, devices, software modules, propagation, networks, user needs, and application scenarios in a way that supports automated reasoning about the needs of the user. This empowers software radios to conduct expressive negotiations among peers about the use of radio spectrum across fluents of space, time, and user context. With RKRL, cognitive radio agents may actively manipulate the protocol stack to adapt known etiquettes to better satisfy the user's needs. This transforms radio nodes from blind executors of predefined protocols to radio-domain-aware intelligent agents that search out ways to deliver the services the user wants even if that user does not know how to obtain them. Software radio provides an ideal platform for the realization of cognitive radio.

  • 210.
    Moy, Linda
    et al.
    New York University School of Medicine.
    Noz, Marilyn E.
    New York University School of Medicine.
    Maguire, Gerald Q., Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Kommunikationssystem, CoS (stängd 2012-01-01).
    Melsaether, Amy
    New York University School of Medicine.
    Deans, Abby E.
    New York University School of Medicine.
    Murphy-Walcott, Antoinette D.
    New York University School of Medicine.
    Ponzo, Fabio
    New York University School of Medicine.
    Role of Fusion of Prone FDG-PET and Magnetic Resonance Imaging of the Breasts in the Evaluation of Breast Cancer2010Inngår i: The Breast Journal, ISSN 1075-122X, E-ISSN 1524-4741, Vol. 16, nr 4, s. 369-376Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this study is to report further about the statistically significant results from a prospective study, which suggests that fusion of prone F-18 Fluoro-deoxy-glucose (FDG) positron emission tomography (PET) and magnetic resonance (MR) breast scans increases the positive predictive value (PPV) and specificity for patients in whom the MR outcome alone would be nonspecific. Thirty-six women (mean age, 43 years; range, 24-65 years) with 90 lesions detected on MR consented to undergo a FDG-PET scan. Two blinded readers evaluated the MR and the computer tomography (CT) attenuation-corrected prone FDG-PET scans side-by-side, then after the volumes were superimposed (fused). A semiautomatic, landmark-based program was used to perform nonrigid fusion. Pathology and radiologic follow-up were used as the reference standard. The sensitivity, specificity, PPV, negative predictive value (NPV), and accuracy (with 95% confidence intervals) for MR alone, FDG-PET alone, and fused MR and FDG-PET were calculated. The median lesion size measured from the MR was 2.5 cm (range, 0.5-10 cm). Histologically, 56 lesions were malignant, and 15 were benign. Nineteen lesions were benign after 20-47 months of clinical and radiologic surveillance. The sensitivity of MR alone was 95%, FDG-PET alone was 57%, and fusion was 83%. The increase in PPV from 77% in MR alone to 98% when fused and the increase in specificity from 53% to 97% were statistically significant (p < 0.05). The false-negative rate on FDG-PET alone was 26.7%, and after fusion this number was reduced to 9%. FDG-PET and MR fusions were helpful in selecting which lesion to biopsy, especially in women with multiple suspicious MR breast lesions.

  • 211.
    Moy, Linda
    et al.
    New York University, Department of Radiology.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Ponzo, Fabio
    New York University, Department of Radiology.
    Deans, Abby E.
    New York University, Department of Radiology.
    Murphy-Walcott, Antoinette D.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Prone mammoPET acquisition improves the ability to fuse MRI and PET breast scans2007Inngår i: Clinical Nuclear Medicine, ISSN 0363-9762, E-ISSN 1536-0229, Vol. 32, nr 3, s. 194-198Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: This study compared prone acquisition of PET scans with traditional supine acquisition to improve fusion of PET scans with MRI scans and improve evaluation of enhancing breast lesions detected on MRI. Materials and Methods: MRI breast scans are acquired in the prone position using a breast coil to allow the breasts to hang pendant. An apparatus was fabricated to allow prone acquisition of PET scans. Fused scans from 2 patients acquired both prone and supine were contrasted with those from 3 patients acquired supine only. All 5 MRI scans were acquired on standard scanners. The PET scans were acquired with a PET/CT unit using a low-dose CT scan for attenuation correction. The PET and MRI volumes were matched twice (using a semiautomated registration method) by different operators. The additional value of fusion was judged using reports from the original (nonfused) MRI and PET, joint rereading of the volumes side by side, and examination of fused images. Results: Of 12 enhancing lesions on breast MRI, 7 demonstrated uptake on PET/CT. In the 3 supine-only cases, the fused images were not interpretable because of the marked distortion of the breasts. In the 2 prone cases, the fused images increased our confidence in characterizing a lesion as benign or malignant. Interpretations were confirmed by clinical follow up in 2 or histologic results in 3 patients. Conclusions: PET MRI fusion is feasible and may assist in localizing lesions detected on either study. A more extensive study is under-way to confirm the value of this fusion technique.

  • 212.
    Moy, Linda
    et al.
    New York University, Department of Radiology.
    Ponzo, Fabio
    New York University, Department of Radiology.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Murphy-Walcott, Antoinette D.
    New York University, Department of Radiology.
    Deans, Abby E.
    New York University, Department of Radiology.
    Kitazono, Mary T.
    New York University, Department of RadiologyNew York University, Department of Radiology.
    Travascio, Laura
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Improving specificity of breast MRI using prone PET and fused MRI and PET 3D volume datasets2007Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 48, nr 4, s. 528-537Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    MRI is a sensitive method for detecting invasive breast cancer, but it lacks specificity. To examine the effect of combining PET with MRI on breast lesion characterization, a prototype positioning device was fabricated to allow PET scans to be acquired in the same position as MRI scans-that is, prone. Methods: To test the hypothesis that fusion of 18F-FDG PET and MRI scans improves detection of breast cancer, 23 patients with suspected recurrent or new breast cancer underwent a routine whole-body PET scan, a prone PET scan of the chest, and a routine breast MRJ scan. The attenuation-corrected prone PET and MRI clatasets were registered twice by different operators. The fusion results were judged for quality by visual inspection and statistical analysis. A joint reading of the MRI and PET scans side by side and integrated images was performed by a nuclear medicine physician and a radiologist. Sensitivity and specificity of MRI and combined MRI and PET scans were calculated on the basis of pathology reports or at least 1 y of clinical and radiologic follow-up. Results: All fusions were verified to be well matched using specific anatomic criteria. A total of 45 lesions was assessed. Lesion size range was 0.6 to 10.0 cm. Of the 44 breasts examined, 29 were suspicious for cancer, of which 15 were found to be positive on surgical excision. In lesion-by-lesion analysis, sensitivity and specificity of MRI alone were 92% and 52%, respectively; after MRI and PETfusion, they were 63% and 95%, respectively. The positive predictive value and the negative predictive value for MRI alone were 69% and 85%, respectively; after MRI and PET fusion, they were 94% and 69%, respectively. Conclusion: Acquisition of prone PET scans using the new positioning device permitted acquisition of prone scans suitable for fusion with breast MRI scans. Fused PET and MRI scans increased the specificity of MRI but decreased the sensitivity in this small group of patients. Additional data are needed to confirm the statistical significance of these preliminary findings.

  • 213. Nakarmi, Prajwol Kumar
    et al.
    Mattsson, John
    Ericsson Research.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Evaluation of VoIP Media Security for Smartphones in the Context of IMS2011Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Market research reports by In-Stat, Gartner, and the Swedish Post and Telecom Agency (PTS) reveal a growing worldwide demand for Voice over IP (VoIP) and smartphones. This trend is expected to continue over the coming years and there is wide scope for mobile VoIP solutions. With this growth in VoIP adoption come challenges related with quality of service and security. Most consumer VoIP solutions, even in PCs, analog telephony adapters, and home gateways, do not yet support media encryption or other forms of security. VoIP applications based on mobile platforms are even further behind in adopting media security. In this paper, we explore the alternatives and feasibility of achieving VoIP media security for smartphones in the realm of IP Multimedia Subsystem (IMS).

  • 214. Noz, M. E.
    et al.
    Maguire, Gerald Q., Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Zeleznik, M. P.
    Olivecrona, L.
    Olivecrona, H.
    Axel, L.
    Srichai, M. B.
    Moy, L.
    Murphy-Walcott, A.
    Clinical application of a semiautomatic 3D fusion tool where automatic fusion techniques are difflicult to use2006Inngår i: Biomedical Image Registration, Proceedings / [ed] Pluim, JPW; Likar, B; Gerritsen, FA, 2006, Vol. 4057, s. 195-205Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The purpose of this paper is to demonstrate the clinical advantages of using semiautomatic volume registration where automatic registration is problematic due to large deformations, small bone anatomy, or extraneous structures. Examples are drawn from clinical cases of MRI/PET breast studies, CT angiography/SPECT cardiac studies, and total wrist arthroplasty. These types of studies should be contrasted with those involving the head, thorax, and pelvis where there is much less deformation and the existence of (some) large bones facilitates automatic matching.

  • 215.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Chung, Grace
    New York University.
    Lee, Benjamin Y.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    DeWyngaert, J. Keith
    New York University.
    Doshi, Jay V.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Murphy-Walcott, Antoinette D.
    New York University.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Kwak, Noeun G.
    UMDNJ --- Robert Wood Johnson Medical School, Piscataway, NJ, USA.
    Enhancing the utility of ProstaScint SPECT scans for patient management2006Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 30, nr 2, s. 123-132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This project investigated reducing the artifact content of In-111 ProstaScint SPECT scans for use in treatment planning and management. Forty-one patients who had undergone CT or MRI scans and simultaneous Tc-99m RBC/In-111 ProstaScint SPECT scans were included. SPECT volume sets, reconstructed using Ordered Set-Expectation Maximum (OS-EM) were compared against those reconstructed with standard Filtered Back projection (FBP). Bladder activity in Tc-99m scans was suppressed within an ellipsoidal volume. Tc-99m voxel values were subtracted from the corresponding In-111 after scaling based on peak activity within the descending aorta. The SPECT volume data sets were merged with the CT or MRI scans before and after processing. Volume merging, based both on visual assessment and statistical evaluation, was not affected. Thus iterative reconstruction together with bladder suppression and blood pool subtraction may improve the interpretation and utility of ProstaScint SPECT scans for patient management.

  • 216.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Erdman, William A.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Menken, K. L.
    Salviani, J. A.
    Modus Operandi for a Picture Archiving and Communication System (PACS)1983Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 149, s. P232-Artikkel i tidsskrift (Fagfellevurdert)
  • 217.
    Noz, Marilyn E.
    et al.
    New York University.
    Erdman, William A.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Maguire Jr., Gerald Q.
    New York University.
    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 .
    Menken, K.L.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Salviani, J. A.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Modus Operandi for a Picture Archiving and Communication System (PACS)1984Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 152, nr 1, s. 221-223Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The authors describe their 18 month experience operating an all digital nuclear medicine department, which led to the development of a system that allows multiple users to access patient reports and images through terminals located in various parts of the hospital. All user interactions are mediated through protocols that automatically acquire, process, display, and archive data. This approach offers distinct advantages over film and paper methods and is applicable in theory to any digital image format.

  • 218.
    Noz, Marilyn E.
    et al.
    New York University.
    Erdman, William A.
    MIDDLESEX GEN UNIV HOSP,RUTGERS MED SCH,NEW BRUNSWICK,NJ 08901 .
    Salviani, J. A.
    Maguire Jr., Gerald Q.
    Schimpf, James H.
    New York University.
    Horii, Steven C.
    New York University.
    Simple Image Acquisition and Analysis Protocols in an Automated Nuclear-Medicine Department1983Inngår i: Medical physics (Lancaster), ISSN 0094-2405, Vol. 10, nr 4, s. 549-Artikkel i tidsskrift (Annet vitenskapelig)
  • 219.
    Noz, Marilyn E.
    et al.
    New York University.
    Kramer, Elissa L.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    McGee, S. A.
    Sanger, J. J.
    New York University.
    An integrated approach to biodistribution radiation absorbed dose estimates1993Inngår i: European Journal of Nuclear Medicine, ISSN 0340-6997, E-ISSN 1432-105X, Vol. 20, nr 2, s. 165-169Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An integrated approach to existing methods of extracting biodistribution data, pharmacokinetics and radiation absorbed dose estimates from serial scintigraphic images is described. This approach employs a single computer-generated user interface to reformat planar scans into a standard file type, align conjugate (anterior and posterior) images, draw regions of interest {(ROIs)} over selected organs and lesions and generate count data for anterior and posterior views and calculated geometric means. Using standard correction methods, the fraction injected activity is obtained for all {ROIs} and total body. This methodology has been applied to the analysis of {indium-III-labelled} breast-cancer-directed antibodies and technetium-90m-labelled {CEA-specific} antibody fragments in non-small-cell lung cancer. It is anticipated that this approach will be useful for evaluating the dosimetry of other radiolabelled monoclonal antibodies, as well as other radiopharmaceuticals.}

  • 220.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    McGee, S. A.
    Sanger, Joseph J.
    New York University.
    Schwimmer, J. J.
    New York University.
    Bae, R.
    New York University.
    An Integrated Approach to Estimating Biodistribution and Radiation Absorbed Dose from Planar Scintigraphic Views of Radiolabeled Monoclonal Antibodies1992Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 33, s. 925-Artikkel i tidsskrift (Fagfellevurdert)
  • 221.
    Noz, Marilyn E.
    et al.
    New York University.
    Kramer, Elissa L.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Scence.
    Sanger, Joseph J.
    New York University.
    An Integrated Approach to Estimating Biodistribution and Radiation Absorbed Dose from Radiolabeled Monoclonal Antibodies-II1993Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 34, nr 5, s. P128-Artikkel i tidsskrift (Fagfellevurdert)
  • 222.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Sanger, Joseph J
    New York University.
    Approach to Estimating Biodistribution and Radiation Absorbed Dose from Planar Scintigraphic Views of Radiolabeled Monoclonal Antibodies - II1993Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 34, nr 5, s. 128 Supplement S-Artikkel i tidsskrift (Fagfellevurdert)
  • 223.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Sanger, Joseph J.
    New York University.
    Chapnick, Jeffrey V
    New York University.
    Megibow, Alec J.
    New York University.
    Birnbaum, Bernard A.
    New York University.
    Fusion of Radiolabeled Monoclonal Antibody SPECT Images with CT/MRI Images1992Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 33, s. 960-Artikkel i tidsskrift (Fagfellevurdert)
  • 224.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Kramer, Elissa L.
    New York University, Department of Radiology.
    Sanger, Joseph J.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Computer Science.
    Fusion of Monoclonal Antibody SPECT and Abdominal CT for Correlation1988Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 169, s. P413-Artikkel i tidsskrift (Fagfellevurdert)
  • 225.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    A Pictorial Database1984Inngår i: Administrative Radiology, ISSN 0738-6974, Vol. 3, nr 11, s. 36-39Artikkel i tidsskrift (Fagfellevurdert)
  • 226.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Calculation of Epsilon(Bar)-Beta, Gamma and Deltai for TC-99m1975Inngår i: The international journal of applied radiation and isotopes, ISSN 0020-708X, E-ISSN 1878-1284, Vol. 26, nr 12, s. 785-786Artikkel i tidsskrift (Fagfellevurdert)
  • 227.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    F-18-FDG PET in detecting primary breast cancer: Reply2007Inngår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 48, nr 10, s. 1752-1752Artikkel i tidsskrift (Annet vitenskapelig)
  • 228.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Multimodality Image Correlation and Fusion1995Inngår i: Clinical SPECT Imaging / [ed] Elissa L. Kramer and Joseph J. Sanger, Ravan Press, 1995, s. 79-95Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 229.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    QSH: a minimal but highly portable image display and handling toolkit1988Inngår i: Computer Methods and Programs in Biomedicine, ISSN 0169-2607, E-ISSN 1872-7565, Vol. 27, nr 3, s. 229-240Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe a software system developed to handle images obtained from different sources, namely, computer-assisted tomography, positron emission tomography, single photon emission tomography and magnetic resonance imaging. In developing the system, it was necessary to address the following points. (1) The types of values that were encountered in both the header information and the pixel elements, namely, integers, floating point numbers, complex numbers and strings. (2) The use of domain-dependent sets of keys, that is, how to choose keys and how to stabilize the use of keys among the user population. This is, for example, how information such as the patient name, or the activity in becquerel is kept. It is necessary to keep both the key values and the units. (3) The development of a method for providing a database using flat files, i.e. linear text. (4) The maintenance of a history of values and operations. This is necessary in order to address the problem of determining from an image was produced. The connection between an image and how it was derived is analogous to describing how a secondary standard is derived from a primary one.

  • 230.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Radiation protection in the health sciences1995 (oppl. 1)Bok (Annet vitenskapelig)
  • 231.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Radiation protection in the health sciences2007 (oppl. 2)Bok (Annet vitenskapelig)
  • 232.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Radiation protection in the radiologic and health sciences1985 (oppl. 2)Bok (Annet vitenskapelig)
  • 233.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    University of Utah, Department of Computer Science.
    Radiation protection in the radiologic and health sciences1979Bok (Annet vitenskapelig)
  • 234.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Birnbaum, B. A.
    New York University.
    Sanger, J. J.
    New York University.
    Kramer, Elissa L.
    New York University.
    Chapnick, J. V.
    New York University.
    Kaminer, E. A.
    New York University.
    Graphical interface for medical image processing1993Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 17, nr 1, s. 1-16Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We have developed a graphical interface which allows users of varying levels of computer experience and proficiency to manipulate medical image-processing data with "point-and-click" ease. The power which had formerly been associated with protocols and shell scripts has been combined with the flexibility and "user-friendliness" of buttons and dialog boxes.

  • 235.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    New York University.
    Erdman, William A.
    New York University.
    Local area networks in an imaging environment1986Inngår i: Critical Reviews in Medical Informatics, ISSN 0882-0503, Vol. 1, nr 1, s. 81-133Artikkel i tidsskrift (Fagfellevurdert)
  • 236.
    Noz, Marilyn E.
    et al.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    Columbia University, Department of Computer Science.
    Horii, Steven C.
    New York University.
    Multimodality image display: Desirable frame buffer characteristics1988Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 12, nr 4, s. 189-200Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The intent of this paper is to understand the characteristics of those frame buffers currently used to display images, versus more ideal frame buffers for medical image display purposes. This study is based on current needs and what characteristics might be desirable. Two case examples are presented: (1) a system developed for high quality computer graphics and (2) a system developed for nuclear medicine and radiation therapy treatment planning. Our study considers: (1) defining a pixel depth sufficient to hold data, (2) the desirability of multiple color look-up tables, (3) how cine loops are managed, and (4) display memory size.

  • 237.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    New York University.
    Horii, Steven C.
    New York University.
    Zeleznik, Michael P.
    Schimpf, James H.
    New York University.
    Baxter, Brent S.
    University of Utah.
    A distribution system for digital images from diverse image sources: Incorporating a local area network in an imaging environment1983Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 7, nr 4, s. 349-361Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes a unified image-processing and viewing system as a viewing station and initially as the central file server in a unified digital image distribution and processing network, linking various digital image sources through a high speed data link and a common image format. The network allows for viewing and processing of all images produced within the complex and for locating viewing stations in any number of convenient areas. The system proposed can be slowly expanded to include all the digital images produced within the department of institution.

  • 238.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University.
    Lee, Evan M.
    New York University.
    Schimpf, James H.
    New York University.
    Graphical Aids for Tomographic Image Correlation1985Inngår i: Computer assisted radiology: Proceedings of the International Symposium / Vorträge des Internationalen Symposiums, West Berlin, FRG: Springer-Verlag Berlin , 1985, s. 608-611Konferansepaper (Fagfellevurdert)
  • 239.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    Columbia University.
    Lee, Evan M.
    New York University.
    Schimpf, James H.
    New York University.
    Horii, Steven C.
    New York University.
    Computerized Correlation of Tomographic Images1984Inngår i: Proceedings of the 1984 International Joint Alpine Symposium, IEEE Computer Society, 1984, s. 85-88Konferansepaper (Fagfellevurdert)
  • 240.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Moy, Linda
    New York University.
    Ponzo, Fabio
    New York University.
    Kramer, Elissa L.
    New York University.
    Can the specificity of MRI breast imaging be improved by fusing 3D MRI volume data sets with FDG PET?2004Inngår i: 2004 2ND IEEE INTERNATIONAL SYMPOSIUM ON BIOMEDICAL IMAGING: MACRO TO NANO, VOLS 1 and 2, IEEE , 2004, s. 1388-1391Konferansepaper (Fagfellevurdert)
    Abstract [en]

    MRI of the breast is an important tool for early detection of breast cancer in women at increased risk for tumor. MRI has a proven track record in identifying tissue abnormalities, but often lacks the ability to characterize this tissue abnormality as benign or malignant, i.e., for certain tissue abnormalities the specificity of MRI is very high, while for others it may be 50% or less. This inability of MRI to differentiate between certain types of tissue abnormalities has lead to our interest in exploring whether the fusion of MRI scans with metabolic imaging (PET) scans can be helpful. 18-FDG PET provides information about the metabolism of the tissue in the breast which in tumors is generally increased. This technique is widely used for detection of other forms of cancer, but has not yet been systematically applied to primary breast cancer, although it has been used to detect local recurrence.

  • 241.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Zeleznik, Michael P.
    Kramer, Elissa L.
    New York University.
    Mahmoud, F.
    Crafoord, Joakim
    Department of Radiology, Karolinska Hospital.
    A versatile functional-anatomic image fusion method for volume data sets2001Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 25, nr 5, s. 297-307Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe and validate a volumetric three-dimensional registration method, and compare it to our previously validated two-dimensional/three-dimensional method. {CT/MRI} and {SPECT} data from 14 patients were interactively fused using a polynomial warping technique. Registration accuracy was confirmed visually and by a nonsignificant F value from multivariate analysis of the transformed landmarks, a significant difference of the squared sum of intensity differences between the transformed/untransformed and the reference volume both at the 0.05 (p {\textgreater} 0.05) confidence level and an average 31\% improvement of the correlation coefficient and cross correlation. For the two-dimensional/three-dimensional method, {ROI} center-to-center distance ranged from 1.42 to 11.32 mm (for liver) with an average of 6.13 mm +/- 3.09 mm. The average {ROI} overlap was 92.51\% with a 95\% confidence interval of 90.20-96.88\%. The new method is superior because it operates on the true three-dimensional volume. Both methods give good registration results, take 10 to 30 min, and require anatomic knowledge.

  • 242.
    Noz, Marilyn E.
    et al.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Zeleznik, Michael P.
    Kramer, Elissa L
    New York University.
    Olivecrona, Lotta
    Karolinska.
    Olivecrona, Henrik
    Karolinska.
    Crafoord, Joakim
    Department of Radiology, Karolinska Hospital.
    Dewyngaert, J. Keith
    New York University.
    Clinical applications from head to toe using a semiautomatic 3D inter/intramodality fusion technique2003Inngår i: BIOMEDICAL IMAGE REGISTRATION / [ed] Gee, JC; Maintz, JBA; Vannier, MW, 2003, Vol. 2717, s. 387-397Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Automated image registration techniques, particularly between modalities which clearly display anatomy and especially within the head, have become commonplace. Meanwhile advances in molecular imaging and the need to perform registration in other areas of body has driven the development of non-rigid and semiautomatic 3D volume fusion methods. This paper will focus on this latter class of 3D volume registration methods for a variety of clinical applications.

  • 243.
    Noz, Marilyn E.
    et al.
    New York University.
    Schimpf, James H.
    New York University.
    Maguire Jr., Gerald Q.
    A modular computer system for the nuclear medicine/ultrasound laboratory1977Inngår i: Radiology, ISSN 0033-8419, E-ISSN 1527-1315, Vol. 124, nr 3, s. 759-762Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Computer-controlled graphic displays are a necessity in many nuclear medicine studies. The authors propose using a set-up consisting of three modules: (a) a display system based on television technology; (b) an instrument interface employing list mode and having a low information loss rate; and (c) flexible modular software which can easily be tailored to the needs of both radiologists and technicians. The authors consider a mini-computer system with broad, flexible applications to be a valuable tool, particularly for those function studies which can only be done by means of nuclear medicine techniques.

  • 244.
    Noz, Marilyn E.
    et al.
    New York University.
    Schimpf, James H.
    New York University.
    Maguire Jr., Gerald Q.
    New York University.
    A modular computer system for the Nuclear Medicine/ultrasound laboratory: A multidisciplinary proposal1977Inngår i: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 1, nr 3, s. 251-261Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In many nuclear Medicine studies computer-controlled graphic displays are an absolute necessity for obtaining meaningful results. Design criteria developed by an interdisciplinary scientific panel are presented to achieve a display system based on television technology; an instrument interface employing list mode using bubble-memory storage technology, thus having a low information-loss rate; and flexible modular software easily tailored to the specific needs of both clinicians and technicians. The panel considers a minicomputer system with broad, flexible applications to be a valuable tool, particularly in doing those function studies that only can be done via nuclear medicine techniques. The final specifications ultimately allow the selection of a vendor and hospital installation, even though all criteria are not currently achievable.

  • 245.
    Ohsawa, Tomoki
    et al.
    Network Research Laboratory, C&C Laboratories, NEC Corporation.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner                               , Mikroelektronik och informationsteknik, IMIT.
    A capacity effect of bridging functionality applied to wireless packet datalink1995Inngår i: Personal, Indoor and Mobile Radio Communications, 1995. PIMRC'95. 'Wireless: Merging onto the Information Superhighway'., New York: IEEE , 1995, s. 1073-1077Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper calculates the capacity efficiency of various data link methods in wireless LAN communications. For LAN communications, the packet reachability between mobile stations within the same cell should be guaranteed, as intracell communication is important. In order to realize this, we have proposed a bridging functionality which automatically transfers the packet at an access point when the source cannot send the packet to destination directly. The theoretical capacity efficiency is calculated and compared against other methods, non-bridging (i.e., direct communications) and full-time bridging (i.e., the access point always bridges data). The evaluation results show that the proposed method is always efficient.

  • 246.
    Ohsawa, Tomoki
    et al.
    Network Research Laboratory, C&C Laboratories, NEC Corporation.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Bridging functionality for medium access control sublayer-applied to distributed foundation wireless medium access control1994Inngår i: 5th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 1994. Wireless Networks - Catching the Mobile Future., The Hague , Netherlands: IEEE , 1994, s. 880-884Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper proposes a new medium access control (MAC) procedure which adds bridging functionality to a multiple access control protocol. This bridging functionality can automatically forward a packet which is sent from a station to others in its local coverage area (i.e., cell). It realizes optimal path selection, from the MAC sublayer point of view. In addition, it provides a broadcast environment to all stations in the coverage area. By utilizing this functionality, throughput and transmission quality can be improved. The concept is simple and easily realized within the distributed foundation wireless medium access control (DFWMAC) proposed to IEEE802.11 standard committee for both infrastructure and ad-hoc networks. It can also effectively deal with the hidden station problem, reduce channel interference and provide throughput improvement. The advantages of this bridging functionality and its operation for both infrastructure networks and ad-hoc networks are discussed.

  • 247.
    Olivecrona, Henrik
    et al.
    Karolinska.
    Hessman, P.
    Sollerman, Christer M.
    Noz, Marilyn E.
    New York University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Mikroelektronik och informationsteknik, IMIT.
    Zeleznik, Michael P.
    A New Method to Evaluate Migration in Total Wrist Arthroplasties Using CT and a Semi-automated Progran for Volume Fusion2004Konferansepaper (Fagfellevurdert)
  • 248.
    Olivecrona, Henrik
    et al.
    Karolinska Institutet, Sweden.
    Maguire, Gerald Q., Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Zeleznik, Michael P.
    University of Utah.
    Kesteris, Uldis
    Department of Orthopedics, Skåne University Hospital.
    Weidenhielm, Lars
    Karolinska Institutet at Karolinska University Hospital Solna.
    A CT method for following patients with both prosthetic replacement and implanted tantalum beads: preliminary analysis with a pelvic model and in seven patients2016Inngår i: Journal of Orthopaedic Surgery and Research, ISSN 1749-799X, E-ISSN 1749-799X, Vol. 11, artikkel-id 27Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Radiostereometric analysis (RSA) is often used for evaluating implanted devices over time. Following patients who have had tantalum beads implanted as markers in conjunction with joint replacements is important for longitudinal evaluation of these patients and for those with similar implants. As doing traditional RSA imaging is exacting and limited to specialized centers, it is important to consider alternative techniques for this ongoing evaluation. This paper studies the use of computed tomography (CT) to evaluate over time tantalum beads which have been implanted as markers. Methods: The project uses both a hip model implanted with tantalum beads, acquired in several orientations, at two different CT energy levels, and a cohort of seven patients. The model was evaluated twice by the same observer with a 1-week interval. All CT volumes were analyzed using a semi-automated 3D volume fusion (spatial registration) tool which provides landmark-based fusion of two volumes, registering a target volume with a reference volume using a rigid body 3D algorithm. The mean registration errors as well as the accuracy and repeatability of the method were evaluated. Results: The mean registration error, maximum value of repeatability, and accuracy for the relative movement in the model were 0.16 mm, 0.02 degrees and 0.1 mm, and 0.36 degrees and 0.13 mm for 120 kVp and 0.21 mm, 0.04 degrees and 0.01 mm, and 0.39 degrees and 0.12 mm for 100 kVp. For the patients, the mean registration errors per patient ranged from 0.08 to 0.35 mm. These results are comparable to those in typical clinical RSA trials. This technique successfully evaluated two patients who would have been lost from the cohort if only RSA were used. Conclusions: The proposed technique can be used to evaluate patients with tantalum beads over time without the need for stereoradiographs. Further, the effective dose associated with CT is decreasing.

  • 249.
    Olivecrona, Henrik
    et al.
    Karolinska Institute, Department of Molecular Medicine and Surgery.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Maguire Jr., Gerald Q.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Sollerman, Christer M.
    Handkirurgiska verksamhetsområdet, Sahlgrenska Universitetssjukhuset/Sahlgrenska, Göteborg.
    Olivecrona, Lotta
    Karolinska Institutet, Department of Clinical Science, Intervention and Technology, Division of Radiology.
    A new computed tomography-based radiographic method to detect early loosening of total wrist implants2007Inngår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 48, nr 9, s. 997-1003Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Diagnosis of loosening of total wrist implants is usually late using routine radiographs. Switching modality to computed tomography (CT) should aid in early diagnosis. Purpose: To propose and evaluate the accuracy of a new CT method for assessing loosening of the carpal component in total wrist arthroplasty. Material and Methods: A protocol encompassing volume registration of paired CT scans of patients with unexplained pain in a prosthetically replaced wrist (used in clinical routine) is presented. Scans are acquired as a dynamic examination under torsional load. Using volume registration, the carpal component of the prosthesis is brought into spatial alignment. After registration, prosthetic loosening is diagnosed by a shift in position of the bones relative to the prosthesis. This study is a preclinical validation of this method using a human cadaverous arm with a cemented total wrist implant and tantalum markers. Seven CT scans of the arm were acquired. The scans were combined into 21 pairs of CT volumes. The carpal component was registered in each scan pair, and the residual mismatch of the surrounding tantalum markers and bone was analyzed both visually and numerically. Results: The detection limit for prosthetic movement was less than 1 mm. Conclusion: The results of this study demonstrate that CT volume registration holds promise to improve detection of movement of the carpal component at an earlier stage than is obtainable with plain radiography.

  • 250.
    Olivecrona, Henrik
    et al.
    Department of Hand Surgery, Södersjukhuset, Stockholm.
    Olivecrona, Lotta
    Karolinska Institutet, Department of Clinical Science, Intervention and Technology, Division of Radiology.
    Weidenhielm, Lars
    Karolinska University Hospital Solna, Department of Orthopedics.
    Noz, Marilyn E.
    New York University, Department of Radiology.
    Kardos, Jocelyn
    New York University, Department of Radiology.
    Maguire, Gerald Q. Jr.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Zeleznik, Michael P.
    Saya Systems Inc., Salt Lake City, UT, USA.
    Aspelin, Peter
    Karolinska Institutet, Department of Clinical Science, Intervention and Technology, Division of Radiology.
    A new technique for diagnosis of acetabular cup loosening using computed tomography - Preliminary experience in 10 patients2008Inngår i: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 79, nr 3, s. 346-353Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background and purpose: Considerable migration of the acetabular cup is required for diagnosis of loosening by conventional radiography. We have developed a new clinically applicable method for assessment of cup loosening using computed tomography (CT). Patients and methods 10 patients scheduled for revision hip replacement due to suspected wear or loosening were scanned twice with CT under torsion loading of the prosthesis. Two independent examiners assessed each patient with respect to motion of the acetabular cup relative to the pelvis using CT volume registration. The CT measurements were compared to findings at revision surgery. Results The method was applicable in 8 of the 10 patients. 1 patient had a severe tremor. In 1 patient, surgery revealed that the hip was ankylotic due to massive ectopic bone formation. This left 8 patients that could be evaluated. 4 cups were loose at surgery, and 3 of these cups could be seen to be mobile by CT. 4 cups that were stable on revision were accurately diagnosed as not being mobile by CT. Movements of less than 1 millimeter between bone and prosthesis could not be distinguished from errors in CT acquisition and volume registration. There was good agreement between the two observers. Interpretation Movement of loose acetabular cups during torsion loading could be detected using CT volume registration. It was sensitive to cup movement in 3 out of 4 cases of loose cups. The method was specific and yielded no false positive results.

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