(0909) Cholesteatoma-Related Temporal Bone Meningoencephalocele: A Case Series and Systematic Literature Review

Introduction: Temporal bone meningoencephalocele (TB-MEC), either with or following cholesteatoma, is a rare and complex neurotological clinical scenario. This study aims to characterize the clinical features and treatment strategies to facilitate clinicians’ decision-making and patients’ counseling.

Methods: We conducted a retrospective case series combined with a systematic literature review between 2000 and 2022. For the literature review, PRISMA guidelines were followed, with articles sourced from PubMed and EMBASE. The study examined demographics, symptoms, imaging findings, surgical approaches, and postoperative outcomes.

Results: We identified 75 cases (n = 72 from the literature and n = 3 original). The majority of the patients with TB-MEC had prior cholesteatoma surgeries (78%), mainly canal wall down mastoidectomy, with a relatively high overall complication rate of 15.3% in a previous surgery. TB-MECs were incidentally discovered during revision in 59.6% of the cases, while 80% of these diagnosed preoperatively had major defects (1cm). Tegmen mastoidum was involved in 68%. Trans-mastoid was chosen in 74.6%, whereas middle fossa or combined approaches were reserved for major defects only. Autologous grafts, mainly temporalis fascia, were the primary choice for reconstruction (98.4%), regardless of defect sizes or surgical approach. Single surgery was mostly sufficient, irrespective of defect size (100% and 93% for minor and major defects), and complications were minimal.

Conclusions: Given the substantial rate of incidental discoveries, our finding emphasizes the need for high suspicious levels of TB-MEC in the context of cholesteatoma, particularly in patients with prior complications and multiple past surgeries, mainly canal wall-down. Employing a single-stage procedure yields positive outcomes with minimal complication rate, providing direction and reassurance for patients and clinicians treating these high-risk cases.