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

Abstract

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

Short Postoperative Length of Stay After Lateral Cerebrospinal Fluid Leak Repair

“…Lateral CSF leaks are a substantial source of morbidity and significantly increase the risk of patients developing meningitis and other serious intracerebral complications. 2 Given that elevated BMI is a risk factor for developing CSF leaks, [4][5][6][7] and obesity rates continue to climb in the United States contributing to larger medical costs, 13 the health care system is likely to see an increasing incidence of patients with CSF leaks who require surgical repair in the coming years. Therefore, developing safe, efficacious, and cost-effective treatment protocols for these patients is of paramount importance.…”

“…3 Spontaneous CSF leaks have been linked to obesity, obstructive sleep apnea, and intracranial hypertension, and are unlikely to resolve without surgical intervention. [4][5][6][7] The connection between CSF leaks and obesity is especially pertinent, given the average body mass index in the United States continues to climb and evidence has suggested a correlated increase in annual referrals for lateral skull base repairs. 8 Three major approaches have been described for the surgical repair of spontaneous lateral CSF leaks: transmastoid (TM), middle cranial fossa (MCF), or combined (TM/MCF).…”

“…Lateral CSF leaks can result from several identifiable sources including trauma, malignancy, and infection, but are often spontaneous 3 . Spontaneous CSF leaks have been linked to obesity, obstructive sleep apnea, and intracranial hypertension, and are unlikely to resolve without surgical intervention 4‐7 . The connection between CSF leaks and obesity is especially pertinent, given the average body mass index in the United States continues to climb and evidence has suggested a correlated increase in annual referrals for lateral skull base repairs 8 …”

Immediate CPAP Use after Skull Base Reconstruction with Hydroxyapatite Bone Cement

“…The prevalence of obstructive sleep apnea (OSA) in sCSF leak patients is 83.3% (10), and OSA is independently associated with calvarial and skull base thinning, implicating OSA in the pathogenesis of sCSF leaks (11).…”

“…Continuous positive airway pressure (CPAP) use is associated with increased middle ear pressure, and there is a positive correlation between CPAP pressure and mean middle ear pressure (13). Thus, there is hesitation to resume PPV after sCSF repair largely because of concern for the development of postoperative tension pneumocephalus from forced air entering the cranial cavity (10,12,14).…”