Bilateral chronic subdural hematomas of the posterior fossae.

An 86-year-old female presented with rare bilateral chronic subdural hematomas (CSHs) of the posterior fossae which were successfully treated by surgical intervention. She had experienced mild head trauma one month before admission. She was transferred to our hospital because of consciousness disturbance and tetraparesis. Magnetic resonance (MR) imaging showed simultaneous occurrence of supratentorial and infratentorial CSHs. We tried to evacuate the CSHs of the bilateral posterior fossae because brainstem compression was markedly severe. Through bilateral burr-hole trepanations, chocolate-colored fluid, not containing clotted components, gushed out under great pressure. Postoperative course was uneventful. MR imaging revealed that the CSHs of the posterior fossae had completely disappeared and brainstem compression had also improved. The patient's neurological deficits were immediately improved after the operation. The patient was discharged one month after the operation for further rehabilitation. Trepanation and evacuation of the hematoma through the posterior fossa might be one of the therapeutic options for posterior fossa CSH, which is similar to supratentorial CSH. However, we considered that the emergency of this rare entity and the method of anesthesia were quite different from supratentorial CSH.