Pathophysiological study of chronic subdural hematoma and communicating hydrocephalus with delayed MRI using Gd-DTPA (Magnevist)

Concerning the pathophysiology of chronic subdural hematoma and communicating hydrocephalus, recent studies have been made, but no definitive conclusion has yet been attained. To study their complicated mechanisms, we examined a delayed MRI which was performed 4 hours after the intravenous injection of Gd-diethylenetriaminepentaacetic acid (Gd-DTPA) on 5 cases of subdural hygroma, 3 cases of chronic subdural hematoma after irrigation, one case of hydrocephalus with glioblastoma, and one case of Parkinson syndrome. In every case of subdural hygroma, it was certified that Gd-DTPA was leaked into the cavity of the subdural space. This is perhaps because the outer and inner membranes of the subdural hygroma consist of fibroblasts and of capillary vessels with fenestration; the leakage of blood composition through this fenestration may promote the growth of the membrane and the cavity. The leakage of Gd-DTPA decreased after irrigation, and it did not recur. In the case of hydrocephalus with gioblastoma, there was leakage of Gd-DTPA into the ventricles surrounding the tumor. This may be because of the destruction of the blood-cerebrospinal fluid barrier; perhaps this is associated with the cause of the communicating hydrocephalus. (author)