High resolution positron emission tomography using 3 mm wide bismuth germanate crystals

摘要: To determine the spatial resolution that can be achieved using 3 mm wide bismuth germanate (BGO) crystals, authors set up a test gantry with opposing groups of 40 BGO crystals and rotating phantom. The motion one group rotation phantom, data acquisition were under computer control. system emulated complete ring 536 on diameter 60 cm, center-to-center spacing 3.5 mm. Coincident acquired only between central 8 detectors, so photon side penetration for off-axis sources would accurately simulated. Clamshell sampling was used to reduce lateral distance 0.9 lead shielding had 1 cm gap, an inner 30 outer cm. Each crystal front face x 10 mm, depth coupled its own 14 phototube. Because phototubes sides array, this coupling scheme is applicable single layer tomograph. At center gantry, 0.35 line source Na-22 amore » reconstructed point spread function (PSF) circular full-width at half-maximum (FWHM) 2.6 from PSF elliptical radial FWHM 4.1 tangential 2.7 These results show small improve in positron tomography by substantial factor.« less