Postoperative MR follow-up of type A aortic dissection

We set out to study the efficacy of MRI in the demonstration of residual alterations and postsurgical complications of type A aortic dissection.

From October 1988 to December 1990, 28 patients, 18 patients with type I and 10 with type II aortic dissection, underwent MR examinations for postsurgical evaluation. Features evaluated included caliber of the aorta (a) above and (b) below the prosthesis; (c) redissection; (d) persistent intimal flap; (e) presence of abdominal vessels arising from the false lumen; and (f) status of thoracic supraaortic vessels.

Five of 28 patients were considered "normal," due to negative results of the assessed parameters. Dilatation of the aorta was found distal to the graft in seven patients and proximal to the graft in two. Redissection was observed in 2 of 28 patients. Residual intimal flap was seen in 15 of 28 patients; the state of false lumen was well identified in 5 patients using only SE images and in 7 of the remaining 10 using phase imaging. In 25 of 28 patients, supraaortic vessels were well evaluated with involvement seen in 2 cases. In the three other patients, adequate identification was not possible.

We believe MRI is the technique of choice for monitoring the aorta after surgery in aortic dissection to identify alterations and complications and institute suitable therapy.