Post-operative Measurement of Intracranial Pressure in Patients Undergoing Surgical Repair of Spontaneous Cerebrospinal Fluid Leak

Introduction: Current evidence suggests that elevated intracranial pressure (ICP) contributes to the development of spontaneous skull base cerebrospinal fluid (CSF) leak. However, patients with spontaneous CSF leak often do not present with clinical features such as papilledema that are classically associated with idiopathic intracranial hypertension (IIH) resulting in delay of diagnosis and treatment.

Methods: This is a retrospective chart review of eight patients that underwent surgical repair for spontaneous CSF leak at a large academic tertiary care center. Patients underwent endoscopic trans-nasal reconstruction of the anterior (n=2) and middle (n=2) skull base or middle fossa craniotomy for repair of a lateral skull base defect (n=4). All patients included in this study were evaluated for elevated ICP via lumbar drain on post-operative day one after surgical repair of their skull base defect. Per the Modified Dandy Criteria, patients were diagnosed with suspected IIH if intracranial pressures were greater than 25 cm H2O. The primary outcome of this study is mean ICP on post-operative day one and the number of patients with suspected or confirmed IIH.

Results: The majority of patients were female (75.0%) with an average BMI of 35.6 kg/m2. On post-operative day one, the mean ICP measurement was 27.1 cm H2O. Seven patients (87.5%) were determined to have elevated ICP above 25 cm H2O. Of these seven patients, one presented with a prior diagnosis of IIH but underwent confirmatory ICP measurement after surgical repair of CSF leak. All patients with suspected or confirmed IIH were referred to neurology and ophthalmology for further evaluation and medical management. Ophthalmologic records were available for five patients with none demonstrating papilledema on exam.

Conclusions: There is a high incidence of elevated ICP suggestive of IIH in patients with spontaneous CSF leak. Expanded diagnostic criteria and improved treatment of IIH may play a role in reducing development and recurrence of spontaneous CSF leak.