Cerebral amyloid angiopathy causing large contralateral hemorrhage during surgery for lobar hemorrhage: a case report.

We report a rare case of cerebral amyloid angiopathy (CAA) causing large contralateral hemorrhage during surgery for lobar hemorrhage. A 62-year-old woman presented with lobar hemorrhage in the left frontal and parietal lobes recurring over the previous 1 month. Because we could not detect the origin of the lobar hemorrhage, we performed a biopsy around the lobar hemorrhage site with the removal of a hematoma. During the surgery, we identified acute brain swelling without bleeding from the operative field. Intraoperative computed tomography demonstrated new large lobar hemorrhage of the right parietal lobe, which we could promptly remove. Specimens around hematomas on both sides were pathologically diagnosed as CAA on immunohistochemical examination. After the surgery, she suffered from lobar hemorrhage three times in the space of only 3 months. To the best of our knowledge, there has been no reported case of CAA causing intracranial hemorrhage of another lesion during surgery. Neurosurgeons should know a possibility of intraoperative hemorrhage in surgeries for lobar hemorrhage caused by CAA.