The architectural impact of single photon transmission measurements on full ring 3-D positron tomography

• Published in: 1995 IEEE Nuclear Science Symposium and Medical Imaging Conference Record Vol. 2; pp. 1026 - 1030 vol.2
• Main Authors: Jones, W., Vaigneur, K., Young, J., Reed, J., Moyers, C., Nahmias, C.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 1995
• Subjects: Attenuation measurement; Detectors; Gamma rays; Noise measurement; Noise reduction; Positron emission tomography; Real time systems; Single photon emission computed tomography; Statistics; Time measurement
• ISBN: 9780780331808; 078033180X
• DOI: 10.1109/NSSMIC.1995.510440

For the full potential of high resolution (2 to 4 mm) full ring 3-D positron emission tomography (PET) to be realized, reductions in both scan time and noise for measured attenuation correction must be provided. Recent advancements in 3-D PET transmission measurements have been demonstrated using a point source and collecting single photon gamma radiation. Greater than an order of magnitude increase in counting statistics for 3-D acquisitions is possible over traditional dual photon techniques such as rotating rods. Usable single photon transmission scans as short as 2 minutes are practical. Such short scans will have reduced noise due to counting rates in excess of 2.5 M events/sec. Acquiring single photon transmission data in full ring 3-D PET requires several architectural additions to the tomograph. Additions include: 1) a "place holding" mode for the coincidence processor, 2) real-time single photon line of response rebinning electronics, 3) a liquid drive for moving a 4 mCi /sup 137/Cs point source at 1 metre/sec around the field of view, and 4) a fiber-optic detector system for tracking the point source position and speed. Initial implementation of these changes supports a first-of-its-kind 82 cm diameter, 23 cm axial length high resolution full ring 3-D PET tomograph.