Patients with moyamoya disease complain of headache before surgery, after surgery, or in both periods. To clarify the pathophysiological features of these headaches which are one of the major symptoms in moyamoya disease after indirect bypass surgery, the authors reviewed data obtained in patients with moyamoya disease who underwent such surgery at their institute.
The authors surveyed 204 children with moyamoya disease younger than 17 years of age who underwent indirect bypass surgery consecutively between 1988 and 2000. If headache and associated symptoms disturbed their daily activity, required rest and/or medication, and occurred at least once a month, the headache was regarded as significant and the patient was included in the study. A postoperative headache was defined as the presence of significant headache 12 months after the operation or later. Preoperative headache was documented in 44 patients. Postoperative headache was observed in 63% (28 of 44) of the patients with preoperative headache and in 6.3% (10 of 160) of those without preoperative headache. Aggravation on postoperative magnetic resonance images or single-photon emission computerized tomography scans did not correlate with this symptom (p = 0.729 and 0.203, respectively). The clinical course had the following features: 1) a coexisting stage of headache and transient ischemic attack; 2) a second stage of headache only; and 3) a final stage of improvement or disappearance of headache.
The authors demonstrated that headaches can persist or develop after indirect bypass surgery despite successful prevention of cerebral ischemia. In addition to decreased cerebral blood flow, progressive recruitment and redistribution of blood flow should be considered as a cause of headaches in patients with moyamoya disease.