CT colonography : Technique and indications

Abstract

Dedicated radiological expertise and ahigh-quality examination, performed according to current technical standards and for accepted indications, are prerequisite to achieve excellent results with CT colonography (CTC). The aim of this article is to review current standards of the examination technique as well as indications and contraindications for CTC based on recent recommendations and guidelines. Based on extensive literature research, current knowledge about the examination technique and the indications and contraindications is summarized. CTC is the radiological examination of choice for the detection of colorectal neoplasia. Beside incomplete or refused colonoscopy and contraindications to colonoscopy, CTC is also anoninvasive option for opportunistic colorectal cancer screening. The examination technique is based on aCTC-specific patient preparation scheme that includes fecal tagging, colonic distension, low-dose CT scans in two patient positions and acombined 2D and 3D data evaluation. Performing CTC according to current technical standards is prerequisite for high-quality examinations and is, thus, also akey factor to obtain acorrect diagnosis. CTC is anoninvasive examination, capable of providing clinically relevant diagnoses for awide range of indications.