Computed tomographic (CT) colonography comprises thin-section CT scanning of the prepared, gas-distended colon, acquired in more than one patient position. The test is widely available internationally and is highly sensitive for colorectal cancer, including significant polyps and early colorectal cancers (SPECC). In this article, we will discuss the basic technique of CT colonography, its diagnostic performance, the challenge of detecting serrated polyps and handling of diminutive polyps. Since CT colonography permits a detailed assessment of polyp morphology, radiologists must communicate their descriptions of the CT appearances of larger polyps accurately and using widely-accepted terminology. This allows services to plan their resection strategy for these larger lesions in timely fashion and ensure availability of appropriate staff and equipment for that patient. Close collaboration between all members of the multi-disciplinary team will ensure that all patients have access to high-quality colonic imaging services.

Computed tomography (CT) coronary angiography is now a widely available and reliable test accessible on basic CT platforms that can exclude coronary heart disease with confidence. It is fast, cheap and, if properly carried out by trained and accredited staff in carefully selected patients, useful information can be obtained with acceptably low radiation exposure in some cases. KeywoRdS Radiation dose, coronary artery disease, CT scanning deClARATion of inTeReSTS No conflicts of interest declared. 1D Eason, 2SJ Leslie, 3AJ Hince, 1JH Miller 1Consultant Radiologist, Department of Radiology; 2Consultant Cardiologist, Department of Cardiology; 3Medical Physicist, Department of Medical Physics and Bioengineering, Raigmore Hospital, Inverness, Scotland, UK Correspondence to JH Miller Consultant Radiologist Raigmore Hospital Inverness IV2 3UJ Scotland tel. +44 (0)1463 704000 e-mail jmiller6@nhs.net

Computed tomography (CT) coronary angiography is now a widely available and reliable test accessible on basic CT platforms that can exclude coronary heart disease with confidence. It is fast, cheap and, if properly carried out by trained and accredited staff in carefully selected patients, useful information can be obtained with acceptably low radiation exposure in some cases.