Functional Hearing Preservation in Vestibular Schwannoma Surgery: Contemporary Microsurgical Approaches and Intraoperative Neurophysiological Monitoring

Vestibular schwannoma presents a significant challenge in contemporary skull base surgery due to the complex balance between tumor control and the preservation of auditory and neurological function. This narrative review examines current scientific evidence regarding hearing preservation, intraoperative neurophysiological monitoring, and microsurgical strategies, incorporating international clinical research, systematic reviews, meta-analyses, and evidence-based guidelines—including contributions from Latin America. The analysis considers preoperative auditory characteristics, tumor dimensions, the selection of surgical approach, electrophysiological monitoring, and long-term functional outcomes. Comparative evidence indicates that the retrosigmoid and middle cranial fossa approaches yield different outcomes depending on the size and anatomical extent of the tumor, with no universal superiority established for either technique. Auditory brainstem responses and direct monitoring of the cochlear nerve provide complementary data on neural integrity during microsurgical manipulation, although evidence supporting the superiority of using these methods in combination remains insufficient. Longitudinal findings show a progressive decline in functional hearing preservation across observation, stereotactic radiosurgery, and microsurgical treatment. Nevertheless, patients who retain functional hearing immediately following surgery may maintain favorable outcomes during long-term follow-up. Methodological differences across studies limit direct comparisons. These findings underscore the necessity for individualized surgical planning, comprehensive preoperative assessment, microsurgical techniques focused on functional preservation, and the accurate interpretation of electrophysiological data. Prospective, multicenter studies—with greater participation from Latin America—are required to standardize functional outcome reporting, strengthen comparative evidence, and optimize both hearing preservation and quality of life.