emission computed tomography (ECT)

emission computed tomography (ECT) [L, emittere, to send forth; computare, to count; Gk, tome, section, graphein, to record] , a form of tomography in which the emitted decay products, such as positrons or gamma rays, of an ingested radioactive pharmaceutical are recorded in detectors outside the body. Computer reconstruction of the data yields a cross-sectional image of the body.