Symptomatic cerebrospinal fluid dissemination of cerebral glioblastoma. Computed tomographic findings in 11 cases.

Computed tomography (CT) findings in eleven patients with symptomatic cerebrospinal fluid (CSF) dissemination from cerebral glioblastoma were analyzed and, in seven cases subsequently autopsied, they were compared with histological observations. Each patient had multiple CT abnormalities including periventricular enhancement (5/11), subarachnoid enhancement (10/11) and progressive hydrocephalus (7/9) by cranial CT, and small filling defects with or without block (5/5) by CT myelography. The areas that showed periventricular or subarachnoid enhancement on CT were confirmed to have macroscopically detectable seeding at autopsy. On the other hand, microscopic deposits were more widely distributed than the enhancement suggested, and were hardly visualized on CT. In association with subarachnoid seeding, we found low-density lesions on CT which had resulted from ischemia or reinvasion of adjacent structures by disseminated glioblastoma and resulting parenchymal edema. By cranial CT, subarachnoid enhancement seems to be a very reliable sign of CSF seeding, whereas periventricular enhancement due to CSF metastases should be carefully distinguished from that due to periventricular tumor infiltration. CT myelography is capable of revealing minute metastatic spinal deposits and may be helpful for ruling out spinal seeding as well as its precise evaluation.