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PubMed · 8772655

Half-cone beam collimation for triple-camera SPECT systems.

J Li·R J Jaszczak·A Van Mullekom·C Scarfone·K L Greer·R E Coleman
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Abstract

UNLABELLED: Cone-beam collimators provide increased sensitivity at similar resolution compared to other collimators. The use of cone-beam collimators for brain imaging with triple-camera SPECT systems, however, results in truncation of the base of the brain because of clearance of the shoulders. A half-cone beam collimator does not have the problem of truncation. The objective of this study was to compare the performance characteristics of half-cone beam with parallel-beam and fan-beam collimators with similar resolution characteristics for SPECT imaging of the brain. METHODS: A half-cone beam collimator with the focal point located towards the base of the brain was built for a triple-camera SPECT system. Spatial resolutions and sensitivities of three collimators were measured. RESULTS: When 10-cm from the collimator surface, the planar spatial resolutions FWHM in mm (point source sensitivities in cps-MBq) for half-cone beam, fan-beam and parallel-beam collimators were 5.2 (85.6), 5.1 (55.6) and 5.9 (39.7), respectively. Image quality was evaluated using a three-dimensional Hoffman brain phantom and patient data. The deeper gray matter were more clearly visualized in the half-cone beam scans. CONCLUSION: Half-cone beam collimation provides higher sensitivity and offers the potential for improved brain imaging compared with parallel-beam and fan-beam collimation when used with a triple-camera SPECT system.

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BrainFemaleGamma CamerasHumansImage Processing, Computer-AssistedMalePhantoms, ImagingSensitivity and SpecificityTomography, Emission-Computed, Single-PhotonComparative StudyJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J Li, R J Jaszczak, A Van Mullekom, C Scarfone, K L Greer, R E Coleman. 1996. Half-cone beam collimation for triple-camera SPECT systems.. https://pubmed.ncbi.nlm.nih.gov/8772655/

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