IMAGING MODALITIES IN THE DIAGNOSIS OF ACUTE AORTIC DISSECTION

The management of patients with acute aortic dissection requires a rap id diagnosis and precise information about the localization and extent of the dissection. Four imaging techniques are currently available to diagnose aortic dissection: aortography; contrast-enhanced computeriz ed tomography (CECT); magnetic resonance imaging (MRI); and transesoph ageal echocardiography (TEE). All of these techniques have their speci fic advantages and inherent limitations. Recent studies have demonstra ted that MRI may best provide a comprehensive and detailed evaluation of the thoracic aorta, therefore proposing this technique as a ''new g old standard'' in the diagnosis of acute aortic dissection. TEE, howev er, may be the best alternative technique, as it combines high sensiti vity and specificity with high practicality. The practicality is parti cularly important in hemodynamically unstable patients in whom a rapid bedside imaging modality is required. CECT might be necessary in sele cted cases in, whom TEE fails to provide a definite diagnosis. Aortogr aphy may be necessary in patients in whom clinical signs are suggestiv e of organ ischemia and in whom coronary anatomy needs to be delineate d before operation.