A Comprehensive Analysis of Lateral Skull Base Meningoencephalocele: Advancing Treatment Protocols for Improved Management of IIH Patients

Introduction: This study focuses on lateral skull base meningoencephaloceles, a condition frequently associated with benign intracranial hypertension (IIH) and significant complications, such as meningitis. Despite its clinical importance, there is limited research on the management of this condition, particularly in the context of the lateral skull base. We developed a new protocol specifically for patients with IIH, aiming to improve treatment outcomes and patient care.

Materials and Methods: A retrospective review was conducted on meningoencephalocele cases treated by the Manchester Skull Base Team from 2010 to 2024. Data were collected on the pathology, clinical presentations, radiological findings, surgical techniques, and postoperative outcomes. For patients with IIH, a specific protocol was implemented, involving discussion at the CSF multidisciplinary team and pre- and postoperative lumbar punctures to measure intracranial pressure.

Results: We identified 37 patients with lateral skull base meningoencephaloceles. Among these, 29.6% presented with meningitis, 18.5% with CSF rhinorrhea, 14.8% with hearing loss, 11.1% with pain, and 7.4% developed brain abscesses. Notably, 17% of the cases were associated with IIH prompting the development of a new management protocol. Notably, a number of patients had a body habitus normally associated with IIH but with no diagnostic imaging features. The protocol involved the measurement of intracranial pressure via lumbar puncture both pre- and post-operatively. Other etiologies identified included iatrogenic causes in 13%, trauma in 8%, and 62% were classified as spontaneous. Surgical intervention was successful in all cases, with 11.1% managed via the middle fossa approach, 40.7% through the transmastoid approach, and 44.4% with a combined approach. Postoperative CSF leaks occurred in 2% of patients and resolved spontaneously.

Conclusion: This comprehensive analysis highlights the significant incidence of IIH among patients with lateral skull base meningoencephaloceles and underscores the high risk of meningitis in this population. The aim of the new protocol was to identify undiagnosed IIH and implement medical treatment to lower intracranial pressure, which has proven effective in improving patient outcomes. We propose that some patients with meningoencephalocele have IIH even in the absence of recognized diagnostic imaging criteria for IIH because of changes to CSF dynamics due to the meningoencephalocele. We further propose that consideration should be given to changing the diagnostic criteria for IIH in the presence of a meningoencephalocele. Our findings contribute to the limited research in this area, demonstrating the need for specialized and tailored approaches in treating this complex and under-researched condition.

Publication History

Article published online:
07 February 2025