Positron Emission Tomography (PET):
Towards Time of Flight
4:00 p.m. (coffee @ 3:30)
PET is a powerful imaging tool that
is being used to study cancer, using a variety of tracers to measure
physiological processes including glucose metabolism, cell proliferation, and
hypoxia in tumor cells. As the utilization of PET has grown in the last several
years, it has become clear that improved lesion detection and quantification
are critical goals for cancer studies. Although physical performance of the
current generation of PET scanners has improved recently, there are limitations
especially for heavy patients where attenuation and scatter effects are
increased. We are investigating new scintillation detectors, scanner designs,
and image processing algorithms in order to overcome these limitations and
improve performance. In particular, we are studying scanner designs that would
incorporate scintillators with improved energy and timing resolution. Improved
energy resolution helps to reduce scattered radiation, and improved timing
resolution makes it feasible to incorporate the time-of-flight information
between the two coincident gamma rays into the image reconstruction algorithm,
a technique that improves signal-to-noise. Results of recent experiments and
computer simulations will be shown to demonstrate these potential improvements.