Helical CT Evaluation of the Thoracic Aorta

Michael B. Gotway, MD, Assistant Professor of Radiology at the University of California, San Francisco and Chief of Thoracic Imaging at San Francisco General Hospital, San Francisco, CA.

Appl Radiol. 2000;29(9) 

In This Article


the development of helical CT and, recently, multidetector-row CT technology, has revolutionized the ability to image the thoracic aorta non-invasively. Helical CT aortography (HCTA) possesses several advantages over other modalities frequently used to investigate thoracic aortic disease, such as transesophageal echocardiography (TEE), MRI, and aortography. the speed, ease, and widespread availability of helical CT make it the examination of choice for acute aortic pathologies such as dissection, intra-mural hematoma, aneurysm, and acute traumatic injury. Helical CT is less operator-dependent than TEE and is easier and faster to perform than either MRI or aortography. These considerations are particularly advantageous in acutely ill patients. Another benefit of helical CT that these other methods do not provide is the ability to image the entire thorax. This is particularly important because cardiovascular abnormalities frequently present with nonspecific symptoms, and nonvascular etiologies of the patient's presentation may be obvious with helical CT. Finally, the volumetric data obtained with helical CT aortography is readily processed using two-dimensional, three-dimensional, or volume-rendering techniques to provide angiogram-like images or images in any desired plane or obliquity.