ABSTRACT
This patient with transient ischemic attacks was found at arteriography of the right carotid tree to have what we felt was a string sign, a narrow appearing internal carotid artery that can often be opened at exploration. The operative findings were, however, surprising and puzzling, and I have never seen such a case before or since. The common, external, and superior thyroid arteries were normal in appearance. The internal carotid was atretic, and was only a tiny string of a vessel as can be seen. I spent a fair amount of time confirming this, dissecting completely around the carotid bulb to be certain that I had not made an unwarranted anatomical assumption, but there were no other vessels. I could not design a surgical strategy to remedy this, so we simply closed the patient and recommended maximal medical therapy. He suffered no harm from the surgical exploration, fortunately.
