Recurrent hyperperfusion after revascularization surgery for adult moyamoya disease: A case report

Direct bypass surgery for moyamoya disease is quite useful for rapidly improving cerebral hemodynamics and resolving ischemic attacks but may induce hyperperfusion syndrome. In this report, we present a rare case of recurrent hyperperfusion after surgery for moyamoya disease. A 47-year-old woman developed left homonymous hemianopsia and was admitted to our hospital. Magnetic resonance (MR) imaging/angiography revealed definitive moyamoya disease presenting with acute cerebral infarction in the right temporoparietal lobe. She was treated with anti-hypertensive agents because she had severe hypertension. She successfully underwent right superficial temporal artery-middle cerebral artery double anastomosis and indirect bypass. A cerebral blood flow study just after surgery demonstrated marked hyperperfusion in the operated hemisphere. A repeat study 2 days later revealed that the hyperperfusion was dramatically improved. Subsequently, however, she developed a severe ipsilateral headache and focal seizure regardless of the blood pressure control. She complained of the headache for >2 weeks. Follow-up MRI showed a small subcortical hemorrhage in the right frontal lobe. Single-photon emission computed tomography revealed that the hyperperfusion relapsed 9 days after surgery and then gradually disappeared. This study shows that preoperative severe hypertension may induce uncontrollable hyperperfusion after direct bypass surgery for moyamoya disease.