Functional MR imaging of anomalies of the aorta.

Stenosis of a vessel is a well-known reason for increased resistance leading to lower flow rates. Other anomalies of the shape or additional blood influx are often considered to be less influential on flow dynamics inside the vessel. In this report, examples of irregular flow patterns in the human aorta are presented. The cases were selected from magnetic resonance examinations of 25 volunteers and more than 150 patients with dysfunctions of the heart or anomalies of the thoracic vessels. The protocol for magnetic resonance examinations included black blood imaging performed in the cine mode (with ECG triggering). Even minor modifications of the aortic shape are shown to result in marked disturbances of the laminar flow pattern in some patients. Effects of abnormal curvatures, additional blood influx, stenoses and dilatation of the aorta are demonstrated.