Patient dose in cardiac computed tomography

Background: Computed tomographic (CT) imaging of the heart is becoming more widely available, and the quality of and interest in these examinations continues to increase. Yet, many physicians who perform or order these exams may be unfamiliar with the radiation doses that are delivered to the patient during specific cardiac CT examinations. Objective: The purpose of this article is to describe several fundamental radiation dose quantities that are used to either measure or report the dose associated with a particular CT examination. In addition, radiation dose estimates are given for coronary artery calcium imaging and coronary angiography performed using either electron beam CT (EBCT) or multi-detector row CT (MDCT) systems.