Prognostic factors associated with perioperative ischemic complications in adult-onset moyamoya disease

Background To clarify the risk factors associated with perioperative ischemic complications in adult-onset moyamoya disease. Material and methods The incidence and causes of perioperative ischemic complications in adult-onset moyamoya disease were retrospectively examined by reviewing 165 surgically treated adult patients. Two hundred forty-six revascularization procedureswere performed in these patients. Results There were 19 (7.7%) perioperative ischemic complications (four infarctions with neurological sequelae and 15 reversible ischemic neurological deficits with a new lesion). The complications occurred in the initially affected hemispheres in 17 (89.4%) of the 19 ischemic complications, regardless of the side of the operation. Multiple ischemic episodes (defined as over four-symptom episodes before treatment), the presence of a preoperative low density area (LDA) on computed tomographic (CT) scanning, and a high signal intensity on diffusionweighted magnetic resonance (MR) imaging were significantly correlated with perioperative ischemic complications (p<0.05, p<0.05, and p<0.01, respectively). Non-surgical hemodynamic risk factors, i.e., hypercapnia, hypocapnia, or hypotension/hypovolemia, were noted in all of the 19 cases. None of the surgical factors evaluated were associated with the complications identified. Conclusions Avoidance of non-surgical hemodynamic risk factors as well as maintaining vital collateral vessels is essential for the prevention of perioperative hemodynamic brain damage in patients with adult-onset moyamoya disease. In addition, very close monitoring of the perioperative care of patients with preoperative multiple ischemic episodes and an LDA or high signal intensity on preoperative CT or diffusionweighted MR imaging is extremely important.