[Radionuclide cisternography for patients suspected of having intracranial hypotension]

We evaluated radionuclide cisternography for the diagnosis of intracranial hypotension in terms of the rate of appearance of abnormal findings in 23 patients, their correlation with therapy, and the most suitable scanning method and timing for visualization of leakage. During the first hour after injection, dynamic lumbar images or consecutively repeated whole-body images were acquired. Whole body images then were acquired at 1, 5, and 24 hours. Until 5 hours after injection, patients were kept in bed resting. Visualization of the leakage (direct finding) and that of the bladder (indirect finding) were observed in 78.3% (18/23) and 60.9% (14/23), respectively. Leakage was visualized most frequently at 5 hours after injection. There were three cases in which the leakage was only visualized at 24 hours. Therefore, there must be cases that show intermittent CSF leakage. To avoid overlooking these cases, a 24-hour whole-body image is also important. The appropriate procedure of radionuclide cisternography is very important to detect CSF leakage, and our procedure proved to be more effective for detecting the abnormal findings.