Institution Experience with a Management Algorithm for Idiopathic Intracranial Hypertension in Meningoencephaloceles and Spontaneous Cerebrospinal Fluid Leaks

Objective: Spontaneous cerebrospinal fluid (sCSF) leaks often arise from meningoencephaloceles located in the anterior or lateral skull base. Idiopathic intracranial hypertension (IIH) is an important etiology in the development of some sCSF leaks. When left undiagnosed or untreated, IIH can result in leak recurrence. Our study assesses the utility of a management algorithm for the diagnosis and treatment of IIH in patients who present with sCSF leaks secondary to anterior or lateral skull base meningoencephaloceles.

Methods: We conducted a retrospective review of patients surgically treated for anterior and lateral skull base sCSF leaks at our institution between 2014 and 2021. Patients were excluded if leaks were iatrogenic, traumatic, or secondary to neoplasms. Opening pressure (OP) measurements were taken at time of lumbar subarachnoid drain placement intraoperatively. High-risk patients (OP > 30 cm H₂O) were recommended for ventriculoperitoneal shunt (VPS). Intermediate-risk patients (OP = 20–29 cm H₂O) were recommended for 4-week course of acetazolamide and repeat lumbar puncture (LP) at 6 weeks. Low-risk patients (OP < 20 cm H₂O) were recommended for repeat LP at 6 weeks. Demographic and radiographic characteristics, management adherence, and outcomes were analyzed.

Results: Our review identified 80 patients with anterior and lateral sCSF leaks. The mean age was 51.9 years and mean BMI was 36.3 kg/m². The median follow-up time was 8.3 months (IQR: 3.3–19.7). Overall, medical, surgical, SA drain-related, and shunt-related complications occurred in 3.8, 10, 1.3, and 1.3% of patients, respectively. One (1.3%) patient experienced postoperative intracranial infection. For the 50 patients with both intraoperative and postoperative OP, while the mean pressures were not significantly different (23.3 vs. 23.0 cm H₂O, p = 0.82), the average absolute difference in OP was 6.6 cm H₂O. When this cohort was stratified into risk categories at postoperative OP, 13 patients (26%) spontaneously escalated to a higher risk category, whereas 18 patients (36%) deescalated to a lower risk category. Three (3.8%) patients experienced an acute recurrent leak within 90 days. Three (3.8%) additional patients developed a remote recurrent leak, on average 48.1 months post-repair. The overall VPS rate was 15.0%. Overall, only 37 patients (46.3%) adhered to the management algorithm.

Conclusions: Utilizing our algorithm of direct meningoencephalocele repair and selective shunting, CSF leak recurrence only occurred in 7.5% of patients and VPS rate was kept low at 15.0%. Overall, while mean intraoperative and postoperative OP measurements are not significantly different, there can be significant variability across OP measurements, with a similar number of patients escalating to a higher risk pressure category as those decreasing to a lower risk category. These findings suggest that multiple pressure checks may be necessary before committing to further IIH treatment ([Figs. 1] and [2]).

Fig. 1 Meningoencephalocele CSF management algorithm.

Fig. 2 Trajectory of opening pressure readings for each patient. (A) Alluvial diagram of leak recurrence plotted against patient trajectory of opening pressure measurements and VPS placement. (B) Alluvial diagram of initial risk category plotted against postoperative opening pressure, VPS placement, and leak recurrence.

Publikationsverlauf

Artikel online veröffentlicht:
05. Februar 2024