Abstract：
:The geometric component of the point spread function (PSF) of a gamma camera collimator can be determined analytically, and the penetration component can be calculated readily by numerical ray-tracing. A Monte Carlo simulation of photon transport which includes collimator scatter is developed. The simulation was implemented with an array processor which propagates up to 1024 photons in parallel, allowing accurate estimates of the total radial PSF in less than a day. The simulation was tested by imaging monoenergetic point sources of Tc-99m, Cr-51, and Sr-85 (140, 320, and 514 keV, respectively) on a General Electric Star Cam with low-energy, general-purpose, and medium-energy collimators. Comparisons of measured and simulated PSFs demonstrate the validity of the model and the significance of collimator scatter in the degradation of image quality.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
De Vries DJ,Moore SC,Zimmerman RE,Mueller SP,Friedland B,Lanza RCdoi
10.1109/42.61758subject
Has Abstractpub_date
1990-01-01 00:00:00pages
430-8issue
4eissn
0278-0062issn
1558-254Xjournal_volume
9pub_type
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