BACKGROUND: Aortic dissection is the most common acute illness of the aorta. It is a life-threatening medical condition associated with high rates of mortality and morbidity. Traditionally, aortography is used to evaluate the presence of this disease entity. However, computed tomographic angiography (CTA) is now preferred because it is less invasive and can also detect associated findings that could lead to the diagnosis of aortic dissection.
OBJECTIVES: The purpose of this study is to determine the accuracy of spiral computed tomography in the diagnosis of aortic dissection in patients with aortic disease.
STUDY DESIGN: This is a validation study of patients who were referred to the Computerized Tomography (CT) AND METHOD Magnetic Resonance Imaging (MRI) section of the Philippine Heart Center for the evaluation of aortic disease. Population includes all patients who underwent CTA and subsequent aneurysmal repair. CTA were reviewed to evaluate the following: site and extent of aortic dissection, size of aortic aneurysm, aortic wall calcification, presence of luminal thrombus, and aortic branch involvement in relation to aortic dissection. The efficacy of CTA was determined using surgery/ histopathology or angiography as gold standard.
RESULTS AND CONCLUSION: The predominant CTA finding is the presence of aneurysm followed by the presence of intimal calcification and thrombus formation. Most of these aneurysms are fusiform type and are commonly seen in the infrarenal segment. Among the 64 patients, dissection was correctly diagnosed by CTA in 18 patients, with 1 false positive finding. The most commonly encountered type of dissection is DeBakey1. Aortic branch extension of dissection (n=3) and presence of hemopericardium (n=4) were seen. With high sensitivity of 100%, specificity of 97.8%, positive predictive value of 94.7, and negative predictive value of 100%, CTA is a useful primary and maybe the only imaging modality needed in the evaluation of aortic dissection.