[A case of agenesis of the corpus callosum accompanied by a ruptured azygos anterior cerebral artery aneurysm and lipoma--a case report].

A 53-year-old woman suffered from sudden onset of severe headache on February 28 in 1982. She was admitted to our hospital soon after onset. On admission, she had a severe headache and nausea, and her consciousness was drowsy. CT scan showed a marked subarachnoid hemorrhage with intracerebral and intraventricular hematoma, a separation of the lateral ventricles with enlargement of posterior horns, and deformity of anterior horn. By these findings, the patient was diagnosed as an agenesis of the corpus callosum with subarachnoid hemorrhage. Left carotid arteriogram revealed an azygos anterior cerebral artery and an aneurysm at the terminal portion of this artery. Surgery was performed on the 24 th day after subarachnoid hemorrhage. Operative finding revealed a little finger's head-sized tumor was situated over the right frontobasal artery. An azygos anterior cerebral artery aneurysm was clipped and tumor was removed. Pathological diagnosis of the tumor was a lipoma. Namely, she had an agenesis of the corpus callosum, an azygos anterior cerebral artery, an aneurysm and a lipoma. There are some reports in which an agenesis of the corpus callosum is accompanied with a lipoma and an azygos anterior cerebral artery is accompanied with an aneurysm. But a case of agenesis of the corpus callosum with an azygos anterior cerebral artery was rarely reported. So this rare case with these anomalies was reported and pathogenesis about the development of 4 anomalies was also discussed.