Rapid recurrence of chronic subdural hematoma by CSF entrapment

: A case of chronic subdural hematoma with multiple rapid recurrences is reported. A 41-year-old woman was admitted to hospital because of a traumatic subarachnoid hemorrhage and an intracerebral hematoma in the left frontal lobe. Both regions were conservatively treated, and she was discharged with no neurological deficit. Four months after this injury, she was readmitted to our clinic with complaints of severe headache and mild left hemiparesis. A CT scan showed a right chronic subdural hematoma. A burr hole and irrigation was performed, and the hematoma cavity disappeared on the following day. However, a deterioration of consciousness and left hemiparesis appeared ten days after the first operation. A second CT scan showed the recurrence of a left chronic subdural hematoma, so a second operation was performed. The patient showed a good postoperative course, and once again the hematoma cavity disappeared on the day following the operation. Nevertheless, a deterioration of consciousness and left hemiparesis appeared eight days after the second operation. A CT scan showed a second recurrence with low-density findings. Intraoperative findings during the third operation showed an almost water-like subdural fluid, and entrapment of cerebrospinal fluid by the inner membrane was suspected. A craniotomy and the removal of the outer and inner membranes were performed. Macroscopically, the inner membrane was intact and showed no signs of injury. No further recurrences occurred after the craniotomy. The suspected cause of the multiple subdural hematomas was the flow and entrapment of cerebrospinal fluid in some area of the inner membrane.