Spontaneous cerebrospinal fluid leakage through fistulas at the clivus repaired with endoscopic endonasal approach

Background: Causes of cerebrospinal fluid (CSF) leakage are primarily traumatic or iatrogenic in origin. In contrast, spontaneous CSF leakage is somewhat rare, and detection of the fistula can be challenging. Meningitis associated with CSF leakage can be life threatening. It is therefore critical to surgically repair the fistula once the underlying cause has been accurately identified. Spontaneous CSF leakage located at the clivus is an extremely rare condition. Case Description: We present the case of a 38‐year‐old male with sudden‐onset headache and subsequent disturbances of consciousness. The patient was diagnosed with severe meningitis caused by CSF leakage through fistulas at the clivus, which were clearly identified on dynamic imaging using high‐resolution computed tomography (CT) with intrathecal injection of contrast medium. After the meningitis was resolved, successful endoscopic repair of the CSF fistula with autologous materials was performed. There has been no recurrence of meningitis for 5 years. Conclusion: Spontaneous CSF leakage at the clivus is an extremely rare condition. High‐resolution CT cisternogram could accurately detect CSF leakage through the clivus. A transnasal endoscopic approach was a useful and reliable method of repairing the fistula at the clivus.