Impact of Cochlear Dose on Hearing Preservation Following Stereotactic Radiosurgery in Treatment of Vestibular Schwannomas: A Multi-center Study. World neurosurgery Chang, S. D., Muacevic, A., Klein, A. L., Sherman, J. H., Romanelli, P., Santa Maria, P. L., Fuerweger, C., Bossi Zanetti, I., Beltramo, G., Vaisbush, Y., Tran, E., Feng, A., Teng, H., Meola, A., Gibbs, I., Tolisano, A. M., Kutz, J. W., Wardak, Z., Nedzi, L. A., Hong, R., MacRae, D., Sohal, P., Kapoor, E., Sabet-Rasekh, P., Maghami, S., Moncada, P. X., Zaleski-King, A., Amdur, R., Monfared, A. 2023


BACKGROUND: Stereotactic radiosurgery (SRS) is a well-established treatment for vestibular schwannomas (VS). Hearing loss remains a main morbidity of VS and its treatments, including SRS. Effects of radiation parameters of SRS on hearing remain unknown.OBJECTIVES: The goal of this study is to determine the effect of tumor volume, patient demographics, pre-treatment hearing status, cochlear radiation dose, total tumor radiation dose, fractionation, and other radiotherapy parameters on hearing deterioration.METHODS: Multicenter retrospective analysis of 611 patients who underwent SRS for VS from 1990-2020 and had pre- and post-treatment audiograms.RESULTS: Pure tone averages (PTA)s increased and word recognition scores (WRS)s decreased in treated ears at 12-60 months while remaining stable in untreated ears. Higher baseline PTA, higher tumor radiation dose, higher maximum cochlear dose, and usage of single fraction resulted in higher post radiation PTA; WRS was only predicted by baseline WRS and age. Higher baseline PTA, single fraction treatment, higher tumor radiation dose, and higher maximum cochlear dose resulted in a faster deterioration in PTA. Below a maximum cochlear dose of 3 Gy, there were no statistically significant changes in PTA or WRS.CONCLUSION: Decline of hearing at 1 year in VS patients after SRS is directly related to maximum cochlear dose, single versus 3-fraction treatment, total tumor radiation dose, and baseline hearing level. The maximum safe cochlear dose for hearing preservation at 1 year is 3 Gy, and the use of 3 fractions instead of 1 fraction was better at preserving hearing.

View details for DOI 10.1016/j.wneu.2023.05.098

View details for PubMedID 37268187