Ultrasonic detection and evaluation of abdominal aortic aneurysms.

Abstract

During the past three years, abdominal ultrasound studies have been performed on over 2,000 patients, of whom 64 proved to have abdominal aortic aneurysms greater than 3.0 cm. in diameter. The technique employed was ultrasonic tomography (B-scanning) wherein a transverse or longitudinal section of the abdomen is preselected and the included structures are outlined by their reflected echo patterns. Since the reflected echo strength is dependent upon changes in acoustic density within the tissue, the elastic walls of the aorta make it a particularly easy structure to demonstrate. The procedure is noninvasive and causes no discomfort. It is routinely possible to outline the contour of the aorta throughout its abdominal course. Although best accomplished by a series of longitudinal scans, excessive tortuosity may necessitate transverse scans for complete evaluation. Abdominal aneurysms are easily identified and may be measured with an accuracy of & 3 mm. Echoes from thrombi may frequently be identified within the aneurysm. The technique is particularly