Symptomatic subdural hygroma after petroclival meningioma surgery. Case report of a intractable complication.

Although subdural hygroma development after craniotomy or aneurysm surgery is a well-known complication and subdural peritoneal or V-P shunt are commonly successful procedures, there are situations that cannot be treated by available surgical options. We reported a case of a 28-year-old young man who developed a symptomatic subdural hygroma after removal of petroclival meningioma. This hygroma increased in size and became bilateral in spite of implantation of V-P with programmable valve at open pressure variable from 30 to 180 mmH 2 O, placement of subdural-peritoneal shunt with low-low valve or without valve and external diversion. The occurrence of this case showed that other factors can play a role in hygroma development as disturbance of normal CSF dynamic with shunt of CSF from basal arachnoidal to subdural spaces secondary to surgery and/or slow growth of petroclival meningioma as well as postoperative progressive cerebral atrophy. Actually there are not effective diagnostic tools to detect causes and therefore there are restricted therapeutic possibilities. This potential and serious complication should be always considered when planning petroclival meningioma surgery because of the severe consequences on functional outcome.