When sensitivity is highest at the center of the field of view, but decreases toward the edges, this describes what aspect of PET scanning?

The correct answer is based on the concept of how PET imaging systems operate, particularly in relation to their sensitivity throughout the field of view (FOV). In PET systems, sensitivity refers to the ability of the scanner to detect gamma photons emitted from a radiopharmaceutical.

At the center of the field of view, the alignment and detection of annihilation photons are optimized, resulting in higher sensitivity. As you move toward the edges of the FOV, the geometry and angles at which these photons are detected become less favorable due to factors like the positioning of detectors and the scatter of photons. This variation in detection efficiency as one moves from the center to the periphery is what defines the sensitivity profile of a PET scan.

Understanding this concept is crucial because it influences image quality and quantitative accuracy, especially in clinical settings where accurate localization of tumors or other pathologies is required. The sensitivity profile directly affects diagnostic capabilities, making it an essential characteristic to be aware of in PET imaging.