(A864) Secondary Cerebrospinal Fluid Leaks and Encephaloceles: Presentation and Strategies for Management

Introduction: Secondary cerebrospinal fluid leaks and encephaloceles that occur due to otitis media, cholesteatoma, or other temporal bone pathology are less well-characterized in the literature, and their management is variable. This study aims to characterize secondary cerebrospinal fluid leaks, surgical approaches, repair methods, relationship with IIH, and key demographics of patients experiencing them.

Methods: Retrospective chart review of 153 patients at a single institution from July 2004 to December 2024 was performed. Patients were identified by ICD codes for cerebrospinal fluid leak. 130 were identified as primary spontaneous leaks, trauma cases, or improper coding and were excluded from analysis. 23 secondary leak patients were analyzed for age at repair, race, body mass index, comorbidities, repair approach, graft techniques, workup/treatment for idiopathic intracranial hypertension (IIH), and follow-up duration.

Results: Average age at presentation was 49.31, the average BMI was 33.93 ± 5.95, and the median follow-up duration was 6.03 years. Most patients presented with symptoms indistinguishable from chronic otitis media or cholesteatoma, such as hearing loss, otorrhea, and headache. Two presented with meningitis. 22% were repaired with a transmastoid approach, 9% via middle fossa approach, and 61% via combined transmastoid and middle fossa approach. 5 were repaired with bone graft alone, 3 with soft tissue alone, and 3 with artificial material alone- though most received a multi-layer repair. 3 underwent IIH workup, leading to ventriculoperitoneal shunt placement in 2. One had recurrence within a year. One had bilateral encephaloceles. Another had a temporal lobe abscess on post-op day 10, requiring surgical evacuation and vancomycin.

Conclusions: This study highlights the varying presentations, surgical approaches, and repair techniques used in patients with a secondary cerebrospinal fluid leak. Key aspects of patients with recurrent leaks, bilateral leaks, and postoperative complications are discussed, and the benefit of screening secondary leak patients for co-morbid IIH is identified.