[A Case of ECA-MCA Double Anastomoses for Hemorrhagic Type of Twig-Like MCA].

Herein, we describe the case of a superficial temporal artery(STA)- and occipital artery (OA)-middle cerebral artery (MCA) double anastomoses that we performed to treat a hemorrhagic twig-like MCA. A 55-year-old man presented to our hospital for investigation of an incidentally identified left MCA occlusion. Left cerebral angiography revealed a twig-like MCA. The (123)I-IMP-single photon emission computed tomography( SPECT) demonstrated no reduction in the cerebral blood flow (CBF), so the patient was initially observed with no treatment. Three months later, he was readmitted with a disturbance of consciousness. The cranial computed tomography revealed a subcortical hemorrhage in the left frontotemporal region and a subdural hematoma. The hematoma was removed via emergency craniotomy. The abnormal vessels were identified and resected, but the parietal branch of the STA was damaged during the skin incision. The histological examination did not reveal the marked fibrous thickening of the intima or wavy internal elastic lamina typically seen with Moyamoya disease. Six months after the initial surgery, a STA-MCA bypass surgery was planned to prevent a future hemorrhage by reducing the hemodynamic overload of the twig-like MCA and improving the cerebral ischemia in the MCA territory that was detected on the preoperative SPECT. However, the parietal branch of the left STA had been injured during the first operation, so we performed a double anastomoses to the MCA using the frontal branch of the STA and the OA. The patient's postoperative course was uneventful and he was discharged 2 weeks after surgery. The follow-up study performed 1 year postoperatively demonstrated no evidence of cerebral infarction and revealed an improvement in the resting CBF and vascular reactivity in the left cerebral hemisphere. No subsequent cerebrovascular events have occurred in this patient during the 7 years since the double anastomoses surgery. Direct bypass for flow conversion from the internal carotid artery to the external carotid artery can be an indispensable treatment for patients with a hemorrhagic twig-like MCA.