By Dr D Regge
Computer-aided diagnosis (CAD) systems are software algorithms designed to assist radiologists in solving a diagnostic problem by using a visual prompt (or “CAD mark”) to direct the observer towards potential pathological lesions. Such algorithms can either be used to help pinpoint areas of disease or to help interpreters decide the nature of abnormal findings. Regardless of the precise role in which CAD is used, the final diagnostic decision must always be made by the human interpreter, who decides whether or not to “believe” and accept the CAD marks.