Aortic dissection occurs when a tear in the inner lining of the aorta allows blood to surge between the layers of the vessel wall, creating a false channel called a false lumen alongside the true lumen. This is a medical emergency because the dissection can block blood flow to vital organs, cause the aorta to rupture, or lead to cardiac tamponade. On ultrasound, a dissection may appear as a flap of tissue within the aorta dividing it into two channels, and color Doppler can show different flow patterns in the true and false lumens. While CT angiography is the gold standard for diagnosing aortic dissection, echocardiography, particularly transesophageal echocardiography, can rapidly identify this condition at the bedside.
Sonography Term