CT Calcium Score is a specialised CT technique that uses very high speed and high resolution images in order to detect calcium on the coronary arteries that supply the heart. No intravenous dye or other preparation is required and the test generally takes less than 15 minutes. The presence of calcium reflects “Coronary Artery Disease” (CAD), and CT can detect it before symptoms (such as a heart attack) occur. The amount of calcium is given as a score, which is compared to a reference group of your age and gender to determine your relative risk of CAD. Early detection allows time to modify risk factors. CT is considered to be very safe and painless.