抄録
We report 4 cases with a ruptured bacterial intracranial aneurysm. A 59-year-old male suddenly became disoriented. A CT scan revealed intracerebral hemorrhage in the right frontal lobe. He presented acute heart failure 4 days after the ictus. An echocardiogram showed perforation of the mitral valve and vegetation at the valve. MRI demonstrated intracerebral hematoma and 6 small round flow voids surrounded by lesions of high-signal intensity on T2-weighted images. Three peripheral aneurysms were depicted on cerebral angiograms. He underwent mitral valve replacement with a heterograft 3 weeks after the ictus. Two of the 3 bacterial aneurysms disappeared after administration of high-dose antibiotics, but an aneurysm arising at the right posterior cerebral artery enlarged and ruptured. He underwent excision of the aneurysm and was discharged from our hospital with homonymous hemianopsia 1 month after the second surgery.
A 62-year-old female with continuous low grade fever for 6 months was diagnosed as having infective endocarditis. She suffered from sudden severe headache 2 weeks after the beginning of antibiotics administration. A CT scan revealed intracerebral hemorrhage in the right frontal lobe. Cerebral angiograms showed an aneurysm at the periphery of the middle cerebral artery. Since the aneurysm did not decrease in size for 2 weeks, we excised it. We did not perform any vascular reconstruction, because retrograde blood flow was confirmed at the orifice of the distal branch. She was discharged without any deficits 1 month after the surgery.
A 46-year-old male having aneurysm of the ascending aorta and aortic regurgitation was admitted to our hospital for treatment of infective endocarditis. He suddenly entered a deep coma, and a CT scan demonstrated a hematoma with massive perifocal edema in the right frontal lobe. He underwent emergency evacuation of the hematoma. Intraoperatively, fresh bleeding from an irregular vascular lesion was seen. This lesion was excised and revealed to be a bacterial aneurysm by histopathological examination. His left hemiparesis was persistent postoperatively.
A 60-year-old female, with a past-history of mitral valve replacement, was admitted to a local hospital for treatment of abdominal pain and hematuria. On the 19th hospital day, she suddenly became unconscious. A CT scan showed a massive intracerebral hematoma and she was transferred to our hospital. Cerebral angiography demonstrated an aneurysm at the periphery of the anterior cerebral artery. The aneurysm was considered to be a ruptured bacterial aneurysm. Her blood pressure could not be maintained and she died the next day.
We discuss the therapeutic strategy for ruptured bacterial aneurysms and emphasize the efficacy of MRI in screening of bacterial intracranial aneurysms.
