Surgical management of spontaneous cerebrospinal fluid leakage through temporal bone defects--case series and review of the literature.

Increasing numbers of cases of idiopathic cerebrospinal fluid (CSF) leakage through temporal bone defects (TBD) have been recently reported, mainly in otolaryngologic journals. Those cases are referred to as spontaneous temporal bone encephaloceles (TBE). Three surgical approaches have been advocated for this condition: the transmastoid approach (TMA), the middle cranial fossa approach (MCFA), or a combination of both. We conducted a retrospective study of all 11 consecutive patients who underwent 12 middle cranial fossa craniotomies for the treatment of CSF leakage through TBD in our institution between 2011 and 2014. Neurosurgical and otologic data were collected from the patients' records. Nine of our cases had an idiopathic etiology. No CSF leaks recurred during an average follow-up of 19.5 months. There was one case of a postoperative expressive aphasia with complete recovery in a few weeks. A systematic literature search was conducted for all studies addressing the treatment of spontaneous TBE between 1986 and 2013. It revealed a trend favoring the use of the MCFA approach over the TMA approach, with an acceptable risk of less than 5% for craniotomy-related complications. We concluded that MCFA is an effective and safe technique for the repair of CSF leakage through TBD. A high percentage of complete resolution with a low complication rate can be achieved with this surgical technique.