A management algorithm for idiopathic intracranial hypertension in skull base meningoencephaloceles.

Objective: In this study, the authors assessed an algorithm for the diagnosis and management of idiopathic intracranial hypertension (IIH) in patients who had undergone surgical repair of skull base meningoencephaloceles presenting with spontaneous cerebrospinal fluid (sCSF) leakage.

Methods: The authors conducted an institutional retrospective review of patients surgically treated for skull base sCSF leaks between 2014 and 2021. Opening pressure (OP) measurements were taken intraoperatively. The algorithm recommended a ventriculoperitoneal shunt (VPS) for high-risk patients (OP ≥ 30 cm H2O), 4 weeks of acetazolamide plus a 2-week washout and repeat lumbar puncture (LP) at 6 weeks for intermediate-risk patients (OP = 20-29 cm H2O), and repeat LP at 4-6 weeks for low-risk patients (OP < 20 cm H2O). Demographics, radiographic characteristics, management adherence, and outcomes were analyzed.

Results: Eighty patients with sCSF leakage were identified. The mean age was 51.9 years, and the mean body mass index was 36.3 kg/m2. The median follow-up was 8.3 months (IQR 3.3-19.7 months). The overall VPS rate was 15.0%. Three patients (3.8%) experienced acute recurrent leakage, and 3 (3.8%) developed remote recurrent leaks (mean time of 48.1 months). For the 50 patients with both intra- and postoperative OPs, the mean OPs were not significantly different (23.3 vs 23.0 cm H2O, respectively, p = 0.82). The mean variability between the two measurements was an absolute difference of 6.6 cm H2O. While 13 patients (26.0%) moved to a higher-risk category based on postoperative OP, 18 patients (36.0%) moved to a lower-risk category.

Conclusions: Utilizing an algorithm of direct meningoencephalocele repair and selective shunting, acute and remote CSF leak recurrence rates were each 3.8%, and the VPS rate was 15.0%. These data provide further insight into CSF dynamics in this population and argue against the theoretical concern that CSF pressure will increase postrepair. Significant intraindividual variability suggests multiple LPs may be necessary before committing to invasive IIH treatment. Further work is necessary to determine the optimal IIH management strategy.