The value of intravascular ultrasound imaging in diagnosis of aortic penetrating atherosclerotic ulcer.

Background: Aortic penetrating atherosclerotic ulcer (PAU) is one of the causes of acute aortic syndrome. Few studies have evaluated the value of intravascular ultrasound (IVUS) imaging in the diagnosis of PAU. Objectives: We aimed to evaluate the value of IVUS imaging in diagnosis of PAU. Methods and results: From September 2002 to May 2005, a consecutive series of 15 patients with suspected aortic dissection underwent both IVUS imaging and spiral Computed Tomography (CT). CT documented 4 PAUs in three patients. There were no complications related to IVUS imaging. The common IVUS features of these four PAUs appeared as a crescentic, localized, outpouching thickened aortic wall with heterogeneous echoic density that communicated with the lumen via a discontinuous intima. By using these features, IVUS detected five other PAUs in four patients, which were overlooked by CT. The width of PAU detected by CT was significantly wider than that of PAU not detected by CT (1.33±0.67cm vs 0.43±0.27cm, P=0.027). Two of five PAUs omitted by initial CT were confirmed by follow-up CT or magnetic resonance imaging (MRI). During follow up, three PAUs, including two of those overlooked by CT, developed into aneurysms. Conclusion: IVUS imaging is a safe examination, and more sensitive than spiral CT to diagnose PAU.