What measurement technique in PET does the Time of Flight method improve?

The Time of Flight (TOF) method in PET significantly enhances spatial resolution. This technique utilizes the timing of detected annihilation photons emitted from positron-electron annihilation, allowing for more precise localization of the radioactive tracer’s origin. By measuring the difference in the arrival times of these photons at the detectors, the system can reconstruct a more accurate picture of the distribution of the radiotracer in the body. This improved localization reduces the uncertainties in spatial positioning, resulting in clearer and more detailed images.

While other factors like count rate and signal processing speed are essential in image acquisition and reconstruction, TOF specifically addresses the challenge of spatial resolution. By reducing the overlap of signals from adjacent sources, TOF helps distinguish between structures that are close together, thereby enhancing the ability to visualize smaller lesions or accurately delineate anatomical features. This is particularly valuable in clinical settings, where high-resolution images can impact diagnosis and treatment planning.