Deciphering normal and anomalous viscero-atrial situs onmultidetector CT angiography

摘要

Viscero-atrial situs encompasses the laterality, relative position andconfiguration of the abdominal viscera, the atria of the heart and thetracheobronchial tree. Determining the situs and cardiac position is the firststep in the commonly used sequential, segmental approach to the imagingevaluation of congenital heart defects (CHD). Abnormalities of visceroatrialsitus and cardiac position are frequently associated with the presence ofcomplex CHDs and accurate assessment of situs abnormalities can help predict theprobability and type of the defect. Multidetector CT (MDCT) angiography, withits multiplanar reformatting and volume rendering techniques, offers accurateinformation about the morphology and three-dimensional relationships of thevarious cardiac and extra cardiac structures. In this pictorial essay, wepresent the MDCT imaging findings of the spectrum of abnormalities ofvisceroatrial situs and cardiac position, using a third generation dual sourceCT scanner.