Electron beam ct

(EBCT), CT examination using a computed tomographic scanner specifically developed for imaging of the heart. It operates by means of a focused electron beam which is magnetically directed at the speed of light across one to four tungsten targets. Each target generates two beams of photons. The photons are detected by a semicircular (180) array of detectors. EBCT operates in three modes varying in acquisition time and spatial resolution. A cine mode acquires a scan in 50 msec and at a rate of 17 scans per second for each anatomical level (Fig.1). A flow mode acquires a scan in 50 msec at a specific phase of the cardiac cycle on sequential or alternating heart beats. A volume mode acquires images in 50 - 100 msec at eight anatomical levels in 200 - 400 msec. Noncontrast-enhanced EBCT is done to detect and quantify coronary artery calcification as a method of assessing risk for significant coronary arterial disease. Contrast-enhanced EBCT is performed for noninvasive imaging of the coronary arteries (Fig.2) and coronary artery bypass grafts. Contrast-enhanced EBCT is used for the diagnosis of congenital and acquired diseases of the aorta, pulmonary arteries and the heart. EBCT and MRI are the most accurate and reproducible imaging methods for quantifying ventricular volumes and mass. Also, see cine CT.

CBH