Temporal Bone Meningoencephalocele Associated with Cholesteatoma:
Systematic Literature Review and a Case Series
Abstract
Background: Temporal bone meningoencephalocele (TB-MEC)
diagnosed with or following cholesteatoma is a rare yet complex
neurotological 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 with a systematic literature review of the
past 3 decades. For the literature review, PRISMA guidelines were
followed, with articles sourced from PubMed and EMBASE. The study
examined demographics, clinical aspects, 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 (79%),
mostly canal wall down (CWD) mastoidectomy, with a relatively high
complication rate (15%) at presentation. TB-MECs were incidentally
discovered intraoperatively in 39.5% of the cases. Most (65%) of the
preoperatively diagnosed had major defects (>1cm). Tegmen
mastoidum was involved in 68%. Surgical treatment employed
trans-mastoid approach in 72%, including minor and major defects,
whereas middle fossa or combined approaches were reserved for major
defects only. Autologous grafts, mainly temporalis fascia, were the
primary choice for reconstruction (98%), 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: Despite advancements
in imaging, TB-MED are still discovered intraoperatively at a
substantial rate. High-risk cases are patients with prior complications
and multiple past surgeries, mainly CWD. Although previously described
complications were ominous, today, a single-stage procedure yields
positive outcomes.