6.**Magnetic resonance imaging (MRI)**

MRI is an accurate investigative modality for acute aortic dissection (sensitivity and specificity, 98%) [18]. It is rarely used in the setting of TAAD where most of the patients are wheeled into operating room as soon as the diagnosis is made. It may have a small role in those patients allergic to iodinated contrast agents or in patients with acute renal failure who are stable enough to undergo MRI.
