Fallopian Canal Meningocele with Spontaneous Cerebrospinal Fluid Otorrhea: Case Report and Systematic Review of the Literature

Objective: To present a case of spontaneous cerebrospinal fluid (CSF) otorrhea from a fallopian canal meningocele involving the geniculate fossa and review all cases of fallopian canal CSF leak reported in the literature with discussion of management and outcomes. Methods: A 53-year-old woman with history of morbid obesity and hypertension presented to a tertiary care referral center with unilateral high-volume CSF otorrhea. High-resolution temporal bone computed tomography demonstrated significant dilatation of the geniculate fossa. Rates of postoperative facial paralysis and refractory CSF leak were reported for the present case and prior cases reported in the literature. Results: Locations of fallopian canal dehiscence, surgical approaches, techniques for packing dehiscence, rates of postoperative facial paralysis and CSF leak, and revision procedures were reported for the present case and 14 cases in the literature. The present case involved dehiscence of the geniculate fossa that was approached via combined transmastoid–middle cranial fossa exploration with facial nerve monitoring. The area of dehiscence was carefully packed with temporalis fascia, muscle, and artificial dural substitute overlay to repair the CSF leak without injuring the facial nerve. Postoperatively, no facial weakness was noted; however, right-sided high-volume CSF otorrhea persisted. After discussing treatment options, the patient underwent subtotal petrosectomy and blind-sac closure of the external auditory canal the following day. This successfully resolved the CSF leak without causing facial nerve weakness. Conclusions: Fallopian canal meningocele is an exceedingly rare cause of CSF otorrhea. Successful repair requires precise packing of the dilated facial canal to occlude the leak without injuring the facial nerve. For refractory CSF leak, subtotal petrosectomy and closure of the external auditory canal warrants consideration.