Calcium Scoring of the Coronary Artery by Electron Beam CT

OBJECTIVE: Our aim was to assess the inter- and intraindividual variability of the attenuation threshold used to identify coronary artery calcification on electron beam CT and to illustrate a new threshold method. MATERIALS AND METHODS: We measured the soft-tissue attenuation of regions surrounding the coronary arteries at the level of the left main coronary artery ostium (high level) and at the bottom of the heart (low level) in 48 consecutive patients (22 men, 26 women). Mean +/- 2 standard deviations (SD) of soft-tissue attenuation and variance of soft-tissue density and SDs were calculated at each level for every patient. It was assumed that setting an attenuation threshold greater than or equal to 3 SDs above that of soft tissue at…