Surgical Approaches for Vestibular Schwannoma

Unexpected recovery from complete deafness to normal hearing post surgical excision of a cerebellopontine angle meningioma: A case report

Background

Cerebellopontine angle (CPA) meningioma presents a significant management challenge due to its intricate relationship with the brainstem neurovascular bundles. The emphasis in the past has been on facial nerve preservation, but the current management standard is hearing preservation in patients with serviceable hearing; however, hearing restoration after complete loss is rare. We report an elderly man who had restoration of hearing in the right ear after complete loss following tumor resection through the retrosigmoid route.

Case Description

A 73-year-old male patient presented with progressive hearing impairment in the right ear, culminating in hearing loss for about 2 months (the American Academy of Otolaryngology-Head and Neck Surgery [AAO-HNS] class D). He also had mild cerebellar symptoms, but other cranial nerves and long tracts were normal. Brain magnetic resonance imaging confirmed a right CPA meningioma, and he had tumor resection through the retrosigmoid route using meticulous microsurgical technique with vestibulocochlear nerve preservation, facial nerve monitoring, and intraoperative video angiography. He had restoration of hearing on follow-up (the American Academy of Otolaryngology-Head and Neck Surgery class A). Histology confirmed World Health Organization central nervous system grade 1 meningioma.

Conclusion

This case illustrates that hearing restoration is possible after complete loss in patients with CPA meningioma. We advocate hearing preservation surgery even in patients with non-serviceable hearing, as the chance of hearing recovery is possible.

Identifying Factors Associated with the Growth of Vestibular Schwannomas: A Systematic Review

BACKGROUND

Surveillance imaging is a valid management option for selected vestibular schwannomas (VS). An ideal protocol for radiologic monitoring would highlight growth-related risk factors and tailor management accordingly. This study aims to identify variables associated with the growth of sporadic VS to enhance surveillance imaging, enable early intervention, and optimize outcomes.

METHODS

The review was conducted according to the PRISMA guidelines. A systematic review of 5 databases (PubMed, Ovid, Cochrane Library, Web of Science, and Google Scholar) was performed to identify negative and positive growth predictors of sporadic vestibular schwannomas. The search was limited to studies reported between January 2015 and January 2020. We conducted an individual patient data meta-analysis using a 1-stage multivariate mixed-effect logistic regression model.

RESULTS

A total of 437 studies were identified, of which 25 met our criteria for full-text analysis. Articles that measured VS with comparable methods were determined eligible for meta-analysis inclusion. The selected articles were highly heterogeneous in their use of grading scales and assessment of tumor size. Our review showed that size at diagnosis (odds ratio, 1.15; 95% confidence interval, 1.11-1.18; P < 0.0001) and intracanalicular localization (odds ratio, 0.49; 95% confidence interval, 0.26-0.90; P = 0.023) were associated with VS growth.

CONCLUSIONS

The factors most frequently reported as being associated with growth within the literature were size of VS at diagnosis and localization of an intracanalicular component. Greater attention should be placed on these criteria within the surveillance imaging algorithm for VS.

Cost Analysis of Cerebrospinal Fluid Leaks and Cerebrospinal Fluid Leak Prevention in Patients Undergoing Cerebellopontine Angle Surgery

OBJECTIVE

To determine if cranioplasty techniques following translabyrinthine approaches to the cerebellopontine angle are cost-effective.

STUDY DESIGN

Retrospective case series.

PATIENTS

One hundred eighty patients with available financial data who underwent translabyrinthine approaches at a single academic referral center between 2005 and 2015.

INTERVENTION

Cranioplasty with a dural substitute, layered fat graft, and a resorbable mesh plate secured with screws Main Outcome Measures: billing data was obtained for each patient's hospital course for translabyrinthine approaches and postoperative cerebrospinal fluid (CSF) leaks.

RESULTS

One hundred nineteen patients underwent translabyrinthine approaches with an abdominal fat graft closure, with a median cost of $25759.89 (range, $15885.65-$136433.07). Sixty-one patients underwent translabyrinthine approaches with a dural substitute, abdominal fat graft, and a resorbable mesh for closure, with a median cost of $29314.97 (range, $17674.28-$111404.55). The median cost of a CSF leak was $50401.25 (range, $0-$384761.71). The additional cost of a CSF leak when shared by all patients who underwent translabyrinthine approaches is $6048.15. The addition of a dural substitute and a resorbable mesh plate after translabyrinthine approaches reduced the CSF leak from 12 to 1.9%, an 84.2% reduction, and a median savings per patient of $2932.23. Applying our cohort's billing data to previously published cranioplasty techniques, costs, and leak rate improvements after translabyrinthine approaches, all techniques were found to be cost-effective.

CONCLUSION

Resorbable mesh cranioplasty is cost-effective at reducing CSF leaks after translabyrinthine approaches. Per our billing data and achieving the same CSF leak rate, cranioplasty costs exceeding $5090.53 are not cost-effective.