Method for identifying 3-D location of gamma interaction and flat panel gamma imaging head apparatus using the same

A method for identifying a 3-D location of gamma interaction, comprising steps of:

• providing an edge-on ends-read imaging head comprising a plurality of edge-on ends-read imaging detectors;
• establishing two expected photopeak relations and a position calibration curve for each crystal in each edge-on ends-read imaging detectors in calibration mode;
• in real practice, obtaining a first energy and a second energy of scintillation photons generated during the detection on a gamma incident event by the edge-on ends-read imaging detectors, wherein the first and second energies lead to two (y,z) coordinates;
• determining whether both set of coordinates point to the same crystal, keep this event for further calculations, if so keep the event, else abandon the event;
• deriving a location index by calculating natural log of ratio of the first energy and second energy with respect to the event whose both set of coordinates point to the same crystal;
• determine two expected energy windows by bringing the derived location index into two (crystal-depending) expected photopeak relations;
• comparing the first energy and the second energy to the two expected energy windows if both the first energy and the second energy fall within the corresponding expected energy windows, keep this event for imaging, else abandon it;
• and
• determine the event location (x coordinate) by bringing the location index into the crystal respective position calibration curve for completing the 3-dimensional coordinate (x, y, z) of the event.