What is the test of choice for suspected aortic dissection?

• A. Chest X-ray
• B. CT Aortogram
• C. MRI of the brain
• D. Echocardiography

Answer: (B)

When aortic dissection is suspected, you need rapid, definitive imaging to confirm the diagnosis and map how far the dissection extends. CT angiography of the chest with IV contrast is the test of choice because it can be performed quickly in the emergency setting, and it provides a clear view of the intimal flap, distinguishes the true lumen from the false lumen, and shows the extent from the aortic root through the arch and into the descending aorta and its branches. This information is essential for deciding on medical management versus urgent surgical intervention and for identifying complications.

MRI offers excellent accuracy but is time-consuming and not ideal in the acute ED scenario. Echocardiography, including bedside transthoracic or transesophageal echo, can be helpful, especially if CT is unavailable or the patient is unstable, but it does not visualize the entire aorta as reliably as CT. Chest X-ray may show mediastinal widening but is nonspecific and not sufficient to diagnose dissection.