GAMMA CAMERA WITH DYNAMIC THRESHOLD

摘要

A method of locating an event with a gamma camera ( 12 ) of an emission computed tomography (ECT) scanner ( 10 ) is provided. The gamma camera ( 12 ) includes a matrix of sensors ( 22 ) situated to view the event. The sensors ( 22 ) have respective outputs that are responsive to the event. The method includes: identifying a first sensor in the matrix that has in response to the event a highest output relative to the other sensors in the matrix (step (B 2 )); identifying a number of second sensors in the matrix that are closest neighbors to the first sensor (step (B 3 )); combining into a total output a number of outputs from the identified sensors, the number of outputs being at least one (1) and less than the number of all the identified sensors (step (B 4 )); and, determining a threshold value which is a percentage of the total output (step (B 4 )).