Intracanalicular Vestibular Schwannoma Treatment
The role of observation, microsurgery, and radiation treatment in the management of Intracanalicular Vestibular Schwannoma continues to evolve.
Watchful waiting is an important management option for patients with minimal symptoms. The literature on the natural history of small vestibular schwannomas continues to expand, with particular emphasis on the expected hearing outcomes.
Microsurgical techniques also focus on hearing preservation. Presence of fundal fluid and good or normal hearing preoperatively are positive predictors of hearing preservation after surgery. Long-term follow-up after radiation therapy for vestibular schwannomas continues to demonstrate excellent tumor control rates, although hearing preservation rates are modest.
Multiple factors, including status of hearing, presence of vestibular symptoms, patient age, medical comorbidities, institutional outcomes, and patient preferences, help determine the management strategy for patients with an intracanalicular vestibular schwannoma 1).
Prevalence of acute sensorineural hearing loss (ASHL) in vestibular schwannoma (VS) patients early after radiosurgery is 8.6%, likely due to radiation injury to the cochlear nerve. Thus, when tumor size is <1.45 cm, serviceable hearing is the criteria for determining whether observation policy (with serviceable hearing) or radiosurgery (lack of serviceable hearing) is given. For those tumor sizes ranged 1.45-3.0 cm, radiosurgery is indicated regardless of hearing level 2).
In the absence of randomized controlled trials and larger cohorts, drawing strong conclusions on which patients to treat depending on their initial hearing status and tumor size remains a matter of debate, especially for intracanalicular vestibular schwannoma 3).