Fallopian Canal Meningocele: A Rare Cause of Cerebrospinal Fluid Otorrhea

Objective Spontaneous cerebrospinal fluid (CSF) leaks from the fallopian canal are extremely rare, with just more than 10 cases reported in the literature. We present a case of spontaneous CSF otorrhea from a fallopian canal meningocele involving the geniculate ganglion.

Study Design Case report.

Setting Academic tertiary care referral center.

Methods Case report and review of the literature.

Results A 53-year-old woman with a history of morbid obesity and hypertension presented with mild right conductive hearing loss and high-volume clear otorrhea in the setting of recent myringotomy for suspected otitis media. The fluid was β-2 transferrin positive. High-resolution temporal bone CT imaging demonstrated dilatation of the geniculate fossa. The patient underwent a combined transmastoid-middle cranial fossa exploration with facial nerve monitoring. Intraoperative findings were significant for an enlarged and dehiscent geniculate ganglion with marked herniation of the leptomeninges through this fallopian canal defect. The area of dehiscence was carefully packed to repair the CSF leak without injuring the facial nerve. Postoperatively, no facial weakness was noted; however, right-sided CSF otorrhea persisted. The patient ultimately returned to the operating room for subtotal petrosectomy and blind-sac closure of the external auditory canal. Significant pneumatization of the temporal bone was noted at the time of secondary repair.

Conclusion Fallopian canal meningocele is an exceedingly rare cause of CSF otorrhea and frequently challenging to treat. Successful repair requires precise packing of the dilated facial canal to completely occlude the leak without injuring the facial nerve. In cases of refractory CSF leak, subtotal petrosectomy and closure of the external auditory canal warrant consideration.