Spontaneous cerebrospinal fluid (CSF) fistulas are infrequent and only 10 cases in the literature have been located in the clivus. We describe two new cases of CSF fistulas in this site and review the literature.

The first patient was a 52-year-old woman referred to our centre for intermittent rhinorrhea that had been diagnosed after an episode of meningitis. The second case was a 69-year-old man who was visited for rhinorrhea of one-year duration; he also developed meningitis during the preoperative study. In both cases, the spontaneous CSF fistula was diagnosed by beta-2-transferrin testing, CT scan and MRI. We performed an endonasal endoscopic transsphenoidal approach and used free grafts and vascularized flaps to close the clival defect. Treatment was successful in both cases.

The physiopathology of spontaneous CSF fistulas remains unknown. Possible explanations given to date in this location are pulsatility of the basilar artery, repeated Valsalva maneuvers and Marfan's disease, the two latter also related to CSF fistulas in other locations. Closure of a CSF leak towards the nasal cavity is mandatory due to potential complications. Our results support the endoscopic transsphenoidal approach using free grafts and/or pediculated flaps as a good alternative to open surgery.