"Hyperdense" aortic wall: potential pitfall in CT screening for aortic dissection.

Opacity of the aortic wall as compared with the nonopacified blood in the lumen has been utilized as one of the criteria for the diagnosis of aortic dissection. It has also been suggested that this finding may be indicative of severe anemia. We evaluated the frequency and implications of aortic wall hyperdensity in 107 consecutive chest CT examinations in patients with no indication of aortic dissection clinically or by other imaging modalities, and whose hematocrit was known. The density of the wall correlated with the patient's age and presence of calcification. Presence or absence of anemia was not a statistically significant factor, although marked conspicuousness of the wall below the age of 60 years did suggest anemia. Atherosclerosis is the most likely explanation for wall visibility in nonanemic patients.