[A case of meningeal carcinomatosis mimicking subarachnoid hemorrhage on MRI].

We report a case of meningeal carcinomatosis that needed to be distinguished from subarachnoid hemorrhage. A 67-year-old female with acute severe headache was admitted to a previous hospital. Since high intensity signal was detected within the parietal cerebral sulci on the right side on brain FLAIR MRI, cerebral angiography was performed due to suspicion of subarachnoid hemorrhage. However, no vascular abnormality was observed. Then, cerebral spinal fluid was collected, which showed an increase in cell count, suggesting meningitis. She was transferred to our hospital for evaluation of neurological disease. After admission to our hospital, there was an episode of hematemesis. Upper gastrointestinal endoscopy was performed, and advanced gastric cancer was found. She was diagnosed as having meningeal carcinomatosis due to gastric cancer. Meningeal carcinomatosis should be considered in addition to subarachnoid hemorrhage when a patient with acute headache shows high intensity signal within the cerebral sulci on brain FLAIR MRI.