An aortogram involves placement of a catheter in the aorta and injection of contrast material while taking x-rays of the aorta. The procedure is known as aortography. The diagnosis of aortic dissection can be made by visualization of the intimal flap and flow of contrast material in both the true lumen and the false lumen. The catheter has to be inserted through the right femoral artery, because in about two thirds of cases the aortic dissection spreads into the left common iliac artery.

The advantage of the aortogram in the diagnosis of aortic dissection is that it can delineate the extent of involvement of the aorta and branch vessels and can diagnose aortic insufficiency.