William Moses | Recent Advances in Time-of-Flight PET

Simple theory predicts that the signal to noise ratio in PET can be reduced by almost an order of magnitude by using time-of-flight (TOF) information. The magnitude of the variance reduction is given by 2D/cDt, where D is the diameter of the object being imaged, c is the speed of light, and Dt is the coincidence timing resolution. The potential impact of this development is large, especially for oncology studies in large “diameter” patients, where it is sorely needed. The noise variance in conventional PET studies tends to increase linearly with the patient “diameter,” so we expect TOF PET imaging to lead to patient studies where the noise variance is independent of patient size. This talk will discuss physics behind the improvement afforded by time-of-flight PET, describe progress on a TOF-PET camera developed at LBNL whose timing resolution is a factor of two better than commercial TOF-PET cameras, and explore the fundamental physical limits of the timing resolution in PET.