Late onset cerebrospinal fluid leakage associated with past head injury.

Late onset cerebrospinal fluid (CSF) leakage, such as rhinorrhea or otorrhea, is a rare complication of closed head injury. We encountered two cases of delayed CSF leakage more than 10 years after head injury. In both cases, surgical treatments were performed using intradural approaches, and the dural defects were closed with viable pedicled flaps. After surgery, the CSF leakage was completely cured and no remarkable complication was observed in either case. The present two cases of late onset CSF leakage suggest that surgical repair procedures should be performed as soon as the leaks are discovered. A bifrontal intracranial approach is recommended to treat frontal cranial base leakage. Temporal craniotomy is recommended to treat temporal base leakage. All cases should be treated using an intradural approach, and the dural defect is best repaired with viable pedicled flaps.