Spontaneous CSF Leaks and Meningoencephaloceles: Endoscopic Repair and Possible Etiology

Objective: To assess the outcomes of endonasal endoscopic repair of spontaneous cerebrospinal fluid (CSF) rhinorrhea and to analyze its possible etiological factors. Patients: During the period between January 1999 and November 2011, 173 patients who presented with spontaneous CSF rhinorrhea underwent endonasal endoscopic surgery. Preoperative examination included CT scans, nasal endoscopy, measurement of glucose concentration in the nasal discharge and, in some cases, cisternographic evaluation via CT or MRI. CSF fistula closure was performed using endonasal endoscopic technique under general anesthesia. In all, 186 surgeries (173 primary attempts and 13 revisions) were carried out over the 12-year period. A combination of different plastic materials, i.e. nasal septum cartilage, facia lata, abdominal fat, rotating middle turbinate flaps, and fibrin glue was used for fistula repair. Results: At the time of the surgery, sites of the CSF fistula were determined as follows: Cribriform plate—70, fovea ethmoidalis—55, sphenoid sinus—45, frontal sinus—3. Extremely pneumatized lateral extension of the sphenoid sinus was found in 26 patients, and a meningo/encephalocele protruding through the bony defect was the source of the leak in 23 of them. In terms of up to 11 years, 165 patients were treated successfully after first attempt and five more recovered after revision endoscopic surgery. Success rate after the first surgery was 95.4%, overall success rate—97.7%. There were no postoperative complications. Conclusion: Possible etiological factors of this disease include obesity, innate skull base malformations, overpneumatized sphenoid sinus, particularly presence of its lateral extensions and the empty sella syndrome. Endoscopic endonasal repair of spontaneous CSF rhinorrhea appears to be a safe and successful procedure. However, technique of endoscopic closure of CSF fistulas in the lateral part of the sphenoid sinus needs further perfection.