Surgical management of spontaneous cerebrospinal fistulas and encephaloceles of the temporal bone

Objectives/Hypothesis: To describe the presentation, surgical findings, and outcomes in patients with spontaneous temporal bone cerebrospinal fluid (CSF) fistulas and encephaloceles. Study Design: Retrospective chart review. Methods: A retrospective chart review of patients treated for a spontaneous temporal bone CSF fistula and/or encephalocele over a 10-year period was performed. Data recorded included demographic information, presenting signs and symptoms, radiographic and laboratory studies, surgical approach, materials used for repair, surgical complications, and successful closure of the CSF fistula. Results: Fifty patients were identified. Five patients underwent bilateral procedures, for a total of 55 surgical repairs. Thirty-seven of the patients were female, with a mean age of 57.2 years. Seventy percent of patients were obese, with a mean body mass index of 35.0 kg/m². The most common presentation was tympanostomy tube otorrhea (68%). Seven patients (14%) presented with meningitis. The middle fossa craniotomy approach was used in 87.3% of cases. Hydroxyapatite bone cement was used in 82.4% of cases. There were four surgical complications: seizure, mastoid infection, tympanic membrane retraction, and a delayed subdural hematoma. There were five persistent or recurrent CSF fistulas that underwent successful revision surgery. Conclusions: Spontaneous CSF fistulas are most common in obese females and should be suspected with a chronic middle ear effusion, persistent otorrhea after tympanostomy tube placement, or in patients with a history of meningitis. The middle fossa craniotomy approach with the use of hydroxyapatite bone cement has a high success rate with a low incidence of postoperative complications. Level of Evidence: 4 Laryngoscope, 128:2170–2177, 2018.