Tips to minimize radiation exposure.

The use of cardiac computed tomography (CT) to noninvasively visualize the coronary arteries has rapidly increased during the last few years but thereby also has raised concerns about the amount of radiation exposure and its potentially associated hazards. In this article, we summarize several strategies and new scanning techniques for dose reduction in cardiac CT, including the following: 1) Coronary CT angiography should not be performed in patients with extensive coronary calcifications because the probability to rule out obstructive coronary artery disease diminishes with increasing coronary artery calcium scores; 2) The scan length in CT angiography should be individually adjusted to the minimum needed length; 3) electrocardiogram-correlated modulation of the tube current should be applied in all patients with stable sinus rhythm; 4) The tube voltage should be reduced to 100 kV in non-obese patients (patient weight <85-90 kg); and 5) A sequential scan mode with prospective electrocardiogram triggering should be considered in patients with a stable heart rate <or=63 beats/min. With the appropriate use of these strategies for dose reduction, the diagnostic image quality is maintained. Therefore, these strategies should be rigidly applied in daily practice to obtain diagnostic images with the lowest possible radiation dose in every patient.