Search Results - "LEWELLEN, T. K"

Depth of interaction decoding of a continuous crystal detector module by Ling, T, Lewellen, T K, Miyaoka, R S

“…We present a clustering method to extract the depth of interaction (DOI) information from an 8 mm thick crystal version of our continuous miniature crystal…”
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Effective count rates for PET scanners with reduced and extended axial field of view by MacDonald, L R, Harrison, R L, Alessio, A M, Hunter, W C J, Lewellen, T K, Kinahan, P E

“…We investigated the relationship between noise equivalent count (NEC) and axial field of view (AFOV) for PET scanners with AFOVs ranging from one-half to twice…”
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Measured count-rate performance of the Discovery STE PET/CT scanner in 2D, 3D and partial collimation acquisition modes by Macdonald, L R, Schmitz, R E, Alessio, A M, Wollenweber, S D, Stearns, C W, Ganin, A, Harrison, R L, Lewellen, T K, Kinahan, P E

“…We measured count rates and scatter fraction on the Discovery STE PET/CT scanner in conventional 2D and 3D acquisition modes, and in a partial collimation mode…”
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Carbon-11-Thymidine and FDG to Measure Therapy Response by Shields, Anthony F, Mankoff, David A, Link, Jeanne M, Graham, Michael M, Eary, Janet F, Kozawa, Susie M, Zheng, Minna, Lewellen, Barbara, Lewellen, Thomas K, Grierson, John R, Krohn, Kenneth A

“…This study was performed to determine if PET imaging with 11C-thymidine could measure tumor response to chemotherapy early after the initiation of treatment…”
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Time-of-flight PET by Lewellen, Tom K.

“…Time-of-Flight (TOF) positron emission tomographs (PET) were developed during the 1980s and early 1990s. Initial investigations into the potential improvements…”
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Evaluation of event position reconstruction in monolithic crystals that are optically coupled by Morrocchi, M, Hunter, W C J, Del Guerra, A, Lewellen, T K, Kinahan, P E, MacDonald, L R, Bisogni, M G, Miyaoka, R S

“…A PET detector featuring a pseudo-monolithic crystal is being developed as a more cost-effective alternative to a full monolithic crystal PET detector. This…”
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FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery by Haselman, M. D., Pasko, J., Hauck, S., Lewellen, T. K., Miyaoka, R. S.

“…Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz…”
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Evaluation of oxygenation status during fractionated radiotherapy in human nonsmall cell lung cancers using [F-18]fluoromisonidazole positron emission tomography by Koh, W J, Bergman, K S, Rasey, J S, Peterson, L M, Evans, M L, Graham, M M, Grierson, J R, Lindsley, K L, Lewellen, T K, Krohn, K A

“…Recent clinical investigations have shown a strong correlation between pretreatment tumor hypoxia and poor response to radiotherapy. These observations raise…”
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Parametric positioning of a continuous crystal PET detector with depth of interaction decoding by Ling, T, Burnett, T H, Lewellen, T K, Miyaoka, R S

“…Here we demonstrate a parametric positioning method on a continuous crystal detector. Three different models for the light distribution were tested. Diagnosis…”
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Imaging of hypoxia in human tumors with [F-18]fluoromisonidazole by Koh, W J, Rasey, J S, Evans, M L, Grierson, J R, Lewellen, T K, Graham, M M, Krohn, K A, Griffin, T W

“…Fluoromisonidazole (FMISO) has been shown to bind selectively to hypoxic cells in vitro and in vivo at radiobiologically significant oxygen levels. When…”
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Glucose metabolism in human malignant gliomas measured quantitatively with PET, 1-[C-11]glucose and FDG : Analysis of the FDG lumped constant by SPENCE, A. M, MUZI, M, OJEMANN, G. A, GRAHAM, M. M, O'SULLIVAN, F, KROHN, K. A, LINK, J. M, LEWELLEN, T. K, LEWELLEN, B, FREEMAN, S. D, BERGER, M. S

“…Calculation of the glucose metabolic rate (MRGlc) in brain with PET and 2-[18F]fluoro-2-deoxy-D-glucose (FDG) requires knowing the rate of uptake of FDG…”
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PET-CT image registration in the chest using free-form deformations by Mattes, D., Haynor, D.R., Vesselle, H., Lewellen, T.K., Eubank, W.

“…We have implemented and validated an algorithm for three-dimensional positron emission tomography transmission-to-computed tomography registration in the…”
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PET imaging using dual-headed gamma cameras: an update by Lewellen, T K, Miyaoka, R S, Swan, W L

“…Interest in clinical fluorodeoxyglucose (FDG) imaging with dual-headed gamma cameras continues to grow. In 1996, Jarritt and Acton published a review article…”
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Simplified FPGA-based data acquisition system for PET by Laymon, C.M., Miyaoka, R.S., Park, B.K., Lewellen, T.K.

“…A data acquisition system for a single-ring, high-resolution, small-animal PET scanner is described. This single-ring test system is part of the development of…”
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Investigation of the performance of the General Electric ADVANCE positron emission tomograph in 3D mode by Lewellen, T.K., Kohlmyer, S.G., Miyaoka, R.S., Kaplan, M.S., Stearns, C.W., Schubert, S.F.

“…Performance measurements of the General Electric ADVANCE Positron Emission Tomograph operating with the septa retracted (3D mode) were made. All…”
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Investigation of the count rate performance of General Electric Advance positron emission tomograph by Lewellen, T.K., Kohlmyer, S.G., Miyaoka, R.S., Schubert, S., Stearns, C.W.

“…A series of 2D and 3D count rate measurements have been carried out on the Advance PET system. The measurements include: NEMA standard protocols; simultaneous…”
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The effect of camera geometry on singles flux, scatter fraction and trues and randoms sensitivity for cylindrical 3D PET-a simulation study by Badawi, R.D., Kohlmyer, S.G., Harrison, R.L., Vannoy, S.D., Lewellen, T.K.

“…Preliminary results of an assessment of the effects of changing the axial field of view (AFOV) and detector ring diameter (DRD) of a cylindrical PET tomograph…”
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A comparison of normalization effects on three whole-body cylindrical 3D PET systems by Badawi, R D, Ferreira, N C, Kohlmyer, S G, Dahlbom, M, Marsden, P K, Lewellen, T K

“…Normalization coefficients in three-dimensional positron emission tomography (3D PET) are affected by parameters such as camera geometry and the design and…”
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Investigation of bias-free positioning estimators for the scintillation cameras by Joung, J., Miyaoka, R.S., Kohlmyer, S.G., Lewellen, T.K.

“…Bias-free positioning estimators for scintillation cameras are investigated. A linear correlation coefficient (LCC) and Chi square error (CSE) method are…”
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Hot sphere detection limits for a dual head coincidence imaging system by Miyaoka, R.S., Kohlmyer, S.G., Lewellen, T.K.

“…Phantom studies were performed to investigate detectability limits for a dual head coincidence imaging system. Spheres of 2.8, 2.2, 1.6, 1.2, 1.0, 0.8 cm inner…”
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