Surgical outcomes of the endonasal endoscopic approach within a standardized management protocol for repair of spontaneous cerebrospinal fluid rhinorrhea

Spontaneous CSF leaks are rare, their diagnosis is often delayed, and they can precipitate meningitis. Craniotomy is the historical "gold standard" repair for these leaks. An endonasal endoscopic approach (EEA) offers potentially less invasiveness and lower surgical morbidity than a traditional craniotomy but must yield the same surgical success. A paucity of data exists studying EEA as the primary management for spontaneous CSF leaks. The authors retrospectively reviewed patients undergoing spontaneous CSF rhinorrhea repair at their institution from July 2010 to August 2018. Standardized management includes EEA as first-line treatment, and lumbar puncture (LP) performed 24-48 hours postoperatively. If opening pressure on LP is elevated, CSF diversion or acetazolamide therapy is used as needed. Perioperative lumbar drains are not used. Of 46 patients identified, the most common CSF rhinorrhea etiology was encephalocele (28/46, 60.9%), and the most common location was cribriform/ethmoid (26/46, 56.5%). Forty-three patients underwent EEA alone, and 3 underwent a simultaneous EEA/craniotomy. The most common repair strategy was nasoseptal or other pedicled flaps (18/46, 39.1%). Postoperatively, 15 patients (32.6%) received CSF diversion due to elevated ICP, with BMI > 40 kg/m2 being a significant risk factor (odds ratio 4.35, p = 0.033) for postrepair shunt placement. Twelve patients received acetazolamide therapy for treatment of mildly elevated pressures. The average opening pressure of the shunted group was 36 cm H2O and the average for the acetazolamide-only group was 26 cm H2O. Two patients underwent CSF leak repair revision, one because of progressive fungal sinusitis and the other because of recurrent CSF leak. The mean follow-up duration was 15 months. The paradigm of EEA repair of spontaneous CSF rhinorrhea with postoperative LP to identify undiagnosed idiopathic intracranial hypertension appears to be safe and effective. In the authors' cohort, morbid obesity was statistically associated with the need for postoperative CSF diversion. This has implications for future surgical treatment as obesity levels continue to rise worldwide.