[Magnetic resonance in postoperative evaluation of aortic dissection]

The value of MRI was investigated in the demonstration of residual alterations and postoperative complications of aortic dissection. October 1988 to December 1992, fifty-nine patients were examined with MRI. The series consisted of 53 patients affected with type A and 6 with type B aortic dissection, all of them surgically treated. The following parameters were studied: 1) aortic dilatation above and 2) below the prosthesis, 3) redissection, 4) persistent intimal flap, 5) origin of abdominal vessels from the false lumen and 6) study of supra-aortic vessels. Twelve of 59 patients were considered normal since all parameters were negative. The aorta was dilated in 19 patients distal to the graft and in 4 proximal to it. Redissection was observed in 33 of 59 patients. Residual intimal flap was clearly demonstrated in 33 of 59 patients; the state of the false lumen was clearly depicted in 12 patients with SE images alone and in 18 of the extant 21 with phase imaging. In 11 of 59 patients abdominal vessels originated from the false lumen. In 53 of 59 patients supra-aortic vessels were clearly demonstrated and appeared to be involved in 10 patients. In 6 cases MRI failed to yield enough information. In our experience MRI is the method of choice for monitoring the aorta after surgical dissection to detect changes and complications and therefore choose the most appropriate treatment.