Prevalence of Elevated Intracranial Pressure in Lateral Spontaneous Cerebrospinal Fluid (CSF) Leaks.

Objective: Evaluate postoperative opening pressures (OP) on lumbar puncture (LP) and polysomnogram (PSG) findings in patients who underwent middle cranial fossa (MCF) repair with lateral spontaneous cerebrospinal fluid (sCSF) leaks.

Study design: Retrospective cohort study.

Setting: Tertiary referral center.

Interventions: MCF repair of sCSF leak, PSG, and postoperative LP.

Main outcome measures: Prevalence of intracranial hypertension (IH; LP OP >25 cm H2O), and of obstructive sleep apnea (OSA) (apnea-hypopnea index [AHI] >5).

Results: Seventy-two patients had an average (standard deviation) age of 56.7 (±11.7) years and BMI of 39.0 (±9.9) kg/m2. There were no unilateral recurrent CSF leaks. OP was completed by 39 patients at a mean 155.5 days (±172.3) postop with a mean OP 22.3 cm H2O (±8.3). Only 10 (32%) patients had an LP ≥25 cm H2O, of which 9 were female and 1 male. Papilledema was observed in 1 of 12 patients on retinal exam. Polysomnogram was completed by 35 patients and OSA was observed in 93% of patients with a mean AHI of 25.6 (±35.1). There was a positive correlation between AHI and elevated OP. All patients with an OP>25 cm H2O had an AHI > 15. In the three patients who developed a contralateral leak, the mean OP was 27.5 (±8.8), AHI 16.5 (±2.5), and mean BMI 37.2 (±12.6). In the four patients with a history of anterior and lateral sCSF leak, mean OP was significantly elevated at 28.75 (±2.9) (p = 0.03). In the six patients with a history of bilateral sCSF leaks, mean OP was also significantly elevated at 31.5 (±6.9) (p = 0.03).

Conclusions: The prevalence of IH on postoperative LP was 32% in lateral sCSF leak patients and nearly all patients had OSA. There was a positive correlation between AHI and elevated OP. All patients should obtain a PSG and those with an AHI >15, multifocal sCSF leaks, or visual symptoms should also obtain a postoperative LP.