Association of benign intracranial hypertension and spontaneous encephalocele with cerebrospinal fluid leak.

OBJECTIVE

To determine the incidence of intracranial hypertension in patients with spontaneous encephalocele with cerebrospinal fluid (CSF) leak.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary care neurotology practice.

PATIENTS

Patients presenting between 2008 and 2011 with spontaneous encephalocele and CSF leak in the temporal bone.

INTERVENTION(S): Lumbar puncture with opening pressure measurement after encephalocele repair.

MAIN OUTCOME MEASURES

Patient age, sex, postoperative course, body mass index, and postoperative intracranial pressure.

RESULTS

Of the 26 patients identified with spontaneous encephalocele with CSF leak, 9 patients had postoperative lumbar puncture data. Of those 9, 89% were female subjects, and 11% were male, with a mean age of 57 and a mean BMI of 41 kg/m (morbidly obese). The mean opening pressure was 24.5 cm H(2)O. Approximately 33% had normal intracranial pressure (mean, 15 cm H(2)O; range, 10-17 cm H(2)O); 67% had elevated intracranial pressure (mean, 29 cm H(2)O; range, 23.5-40 cm H(2)O). The incidence of BIH in the general population is 0.001%. Of the 6 with intracranial hypertension, 3 (50%) were placed on acetazolamide for fundoscopic findings, postoperative headache, and/or visual changes. Mean time to LP after repair of encephalocele was 13 months (range, 4 days to 75 months).

CONCLUSION

This study shows that benign intracranial hypertension is prevalent in a significant number of patients presenting with spontaneous encephalocele with CSF otorrhea at a rate much higher than is found in the general population. This finding has direct clinical implications and suggests that all patients with spontaneous encephalocele/CSF leak warrant evaluation for benign intracranial hypertension.