James George Colsher

Journal Article Eur Radiol · December 2013 OBJECTIVES: To investigate the impact of an adaptive statistical iterative reconstruction (ASiR) algorithm on diagnostic accuracy and confidence for the diagnosis of hypervascular liver tumours, as well as the reader's perception of image quality, using a ... Full text Link to item Cite

Patient-specific radiation dose and cancer risk for pediatric chest CT.

Journal Article Radiology · June 2011 PURPOSE: To estimate patient-specific radiation dose and cancer risk for pediatric chest computed tomography (CT) and to evaluate factors affecting dose and risk, including patient size, patient age, and scanning parameters. MATERIALS AND METHODS: The inst ... Full text Link to item Cite

Patient-specific dose estimation for pediatric abdomen-pelvisCT

Journal Article Progress in Biomedical Optics and Imaging Proceedings of SPIE · June 15, 2009 The purpose of this study is to develop a method for estimating patient-specific dose from abdomen-pelvis CT examinations and to investigate dose variation across patients in the same weight group. Our study consisted of seven pediatric patients in the sam ... Full text Cite

Ultra Low Dose CT for Attenuation Correction in PET/CT

Conference 2008 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (2008 NSS/MIC), VOLS 1-9 · January 1, 2009 Featured Publication Link to item Cite

Ultra low dose CT for attenuation correction in PET/CT

Journal Article IEEE Nuclear Science Symposium Conference Record · December 1, 2008 In this paper, we present an ultra low-dose CT acquisition and reconstruction technique that provides sufficient image quality for PET attenuation correction while keeping the CT dose to a minimum. With PET/CT, CT is used instead of radioactive transmissio ... Full text Cite

Image quality vs. NEC in 2D and 3D PET

Journal Article IEEE Nuclear Science Symposium Conference Record · December 1, 2005 To investigate the relationship between NEC and image quality in 2D and 3D PET, while simultaneously optimizing 3D low energy threshold (LET), we have performed a series of phantom measurements. The phantom consisted of 46 1 cm fillable hollow spheres on a ... Full text Cite

Performance of a BGO PET/CT with higher resolution PET detectors

Journal Article IEEE Nuclear Science Symposium Conference Record · December 1, 2005 A new PET detector block has been designed to replace the standard detector of the Discovery ST PET/CT system. The new detector block Is the same size as the original, but consists of an 8×6 (tangential x axial) matrix of crystals rather than the original ... Full text Cite

Adjusting the low energy threshold for large bodies in PET

Journal Article IEEE Nuclear Science Symposium Conference Record · December 1, 2004 Featured Publication The performance of a PET scanner on three different phantom sizes was studied as a function of low energy threshold (LET). Phantom cross sections ranged from 20 cm diameter circular to 28 cm × 43 cm oval and LET's ranged from 350 keV to 475 keV, in 25 keV ... Cite

Standardized tests of PET performance.

Journal Article J Nucl Med · July 1992 Link to item Cite

Performance standards in positron emission tomography.

Journal Article J Nucl Med · December 1991 A standard set of performance measurements is proposed for use with positron emission tomographs. This set of measurements has been developed jointly by the Computer and Instrumentation Council of the Society of Nuclear Medicine and the National Electrical ... Link to item Cite

A hexagonal bar positron camera: Problems and solutions

Journal Article IEEE Transactions on Nuclear Science · January 1, 1983 Featured Publication Full text Cite

Effects of wobbling motion on image quality in positron tomography

Journal Article IEEE Transactions on Nuclear Science · January 1, 1981 Featured Publication The design of any positron emission tomograph involves some compromises. In particular, the simultaneous goals of high sensitivity and good resolution have resulted in circular ring systems using relatively large crystals and rotation/wobbling motions. The ... Full text Cite

Correction for field nonuniformity in scintillation cameras through removal of spastial distortion.

Journal Article J Nucl Med · August 1980 Featured Publication A method to correct for the spatial distortions of gamma cameras has been developed. The method consists of two parts: measuring spatial distortions and repositioning events during accumulation. Distortions are measured using a pattern consisting of parall ... Link to item Cite

Fully three-dimensional positron emission tomography.

Journal Article Phys Med Biol · January 1980 Featured Publication Fully three-dimensional positron emission tomography is considered and a reconstruction algorithm derived. The reconstruction problem is formulated mathematically as a three-dimensional convolution integral of a point spread function with an unknown positr ... Full text Link to item Cite

Use of position sensitive detectors in positron imaging

Journal Article IEEE Transactions on Nuclear Science · January 1, 1980 Featured Publication The use of Anger-type bar cameras for positron imaging results in a totally stationary system. In addition, the design is cost effective since the Anger principle will provide many resolution elements using only a few crystals and photomultipliers. Pulse s ... Full text Cite

Iterative three-dimensional image reconstruction from tomographic projections

Journal Article Computer Graphics and Image Processing · December 1977 Featured Publication Full text Cite