Vascular rings: a practical approach to imaging diagnosis.

Vascular ring is a term given to a combination of vascular and often ligamentous structures that encircle the trachea and esophagus. The diagnosis can be difficult because clinical symptoms can be variable and nonspecific, and because vascular arrangements that result in vascular rings in some patients do not form vascular rings in others. The clinical manifestations comprise a spectrum ranging from no symptoms to feeding difficulties, repeated infections, and life-threatening respiratory compromise. The diagnosis of vascular ring can be made by various imaging modalities. Therefore it is imperative that pediatric radiologists be familiar with the anatomic variants that can result in a symptomatic ring needing surgical repair, their imaging appearance and the appropriate imaging algorithm. The goals of this manuscript are to describe common and uncommon types of vascular rings, to simplify the differential diagnosis, and to outline the imaging options for accurate diagnosis.