Anterior and Lateral Skull Base Spontaneous CSF Leaks: Evaluation of Comorbidities and Treatment Outcomes

To evaluate clinical characteristics and outcomes of patients diagnosed with anterior (ASB) or lateral skull base (LSB) spontaneous cerebrospinal fluid (sCSF) leak.

Single center retrospective review of patients diagnosed with sCSF leaks of ASB or LSB between 1/1/2009 and 11/1/2019 (n = 69). Body mass index (BMI), gender, age at diagnosis, origin of CSF leak (ASB vs LSB), surgical approach, lumbar drain use, recurrence, pre-operative diagnosis of diabetes mellitus (DM), and obstructive sleep apnea (OSA) were collected.

69 patients included in this study met criteria for sCSF leak without a traumatic or iatrogenic cause (Female: 51 (74%); average BMI: 37.0 ± 7.9). Forty-eight (70.0%) presented with sCSF leaks of the lateral skull base. All ASB leaks were treated with an endoscopic transnasal approach. Eleven (22.9%) LSB leak patients were treated using transmastoid approaches and 35 (72.9%) patients with a middle cranial fossa approach. Eleven patients (15.9%) reported sCSF leak recurrence. Two patients (9.5%) with anterior skull base and 9 patients (18.8%) with lateral skull base leaks had recurrence. LSB sCSF leaks had a relative risk of 2.192 of recurrence compared to ASB leaks (95% CI: 0.431-11.157, P = .483). A 5.017 times increased risk (95% CI: 1.285-19.583, P = .020) was reported for patients with OSA, while the risks for DM and BMI were 1.351 (95% CI: 0.67-9.105, P = .177) and 1.026 (95% CI: 0.963-1.094, P = .426) respectively. Patients with sCSF leak recurrence had significantly lower lumbar drain use (33.3%) than those without recurrence (72.7%) (P = .049).

Spontaneous CSF leak recurrence is complex and multifactorial, and while patients with both DM and OSA had the higher risk of recurrence, OSA is likely an independent clinical risk factor for sCSF leak recurrence in this patient population.