Optimizing outcomes in the management of patients with vestibular schwannomas (VSs) requires consideration of the patient’s goals. Earlier recognition of VS by imaging has led to an evolution in management. Stereotactic radiosurgery (SRS) has emerged as a frequently used strategy designed to reduce management risks, obtain long-term tumor control, and preserve current neurological function. The authors analyzed features that impact hearing preservation rates in patients with serviceable hearing prior to SRS.
The study included 307 patients who had serviceable hearing (Gardner-Robertson hearing scale [GR] grade 1 or 2, speech discrimination score ≥ 50%, pure tone average ≤ 50 dB) at the time of SRS. The authors evaluated parameters that included age, tumor volume, hearing status, disequilibrium, tinnitus, Koos class, sex, and tumor margin dose. The Pittsburgh Hearing Prediction Score (PHPS) was evaluated as a method to predict long-term hearing outcomes in these cases.
At a median of 7.6 years after SRS (range 1–23 years), tumor control was achieved in 95% of patients. The overall serviceable hearing preservation rate was 77.8% at 3 years, 68.8% at 5 years, and 51.8% at 10 years. The PHPS assigns a total of 5 points based on patient age (1 point if < 45 years, 2 points if 45–59 years, and 3 points if ≥ 60 years), tumor volume (0 points if < 1.2 cm3, 1 point if ≥ 1.2 cm3), and GR grade (0 points if grade 1 hearing, 1 point if grade 2 hearing) The serviceable hearing preservation rate was 92.3% at 10 years in patients whose score total was 1. In contrast, none of the patients whose PHPS was 5 maintained serviceable hearing at 10 years (p < 0.001).
SRS resulted in a high rate of long-term tumor control and cranial nerve preservation. The PHPS helped to predict long-term hearing preservation rates in patients who underwent SRS when they still had serviceable hearing. The best long-term hearing preservation rates were found in younger patients with smaller tumor volumes.
ABBREVIATIONSGR = Gardner-Robertson hearing scale; NF2 = neurofibromatosis type 2; PHPS = Pittsburgh Hearing Prediction Score; PTA = pure tone average; ROC = receiver operating characteristic; SDS = speech discrimination score; SRS = stereotactic radiosurgery; VS = vestibular schwannoma.
Correspondence Hideyuki Kano: University of Pittsburgh, Pittsburgh, PA. firstname.lastname@example.org.INCLUDE WHEN CITING Published online September 6, 2019; DOI: 10.3171/2019.5.JNS182765.
S.J. and H.K. contributed equally to this work.
Disclosures The work described in this report was funded by a research grant to Dr. Kano from AB Elekta, Stockholm, Sweden. Dr. Lunsford reports being a consultant for the Insightec Data and Safety Monitoring Board (DSMB) and an AB Elekta stockholder.
AkpinarBMousaviSHMcDowellMMNiranjanAFarajiAHFlickingerJC: Early radiosurgery improves hearing preservation in vestibular schwannoma patients with normal hearing at the time of diagnosis. Int J Radiat Oncol Biol Phys95:729–7342016
AkpinarB, MousaviSH, McDowellMM, NiranjanA, FarajiAH, FlickingerJC, : Early radiosurgery improves hearing preservation in vestibular schwannoma patients with normal hearing at the time of diagnosis. 95:729–734, 2016)| false
HasegawaTKidaYKatoTIizukaHYamamotoT: Factors associated with hearing preservation after Gamma Knife surgery for vestibular schwannomas in patients who retain serviceable hearing. J Neurosurg115:1078–10862011
HasegawaT, KidaY, KatoT, IizukaH, YamamotoT: Factors associated with hearing preservation after Gamma Knife surgery for vestibular schwannomas in patients who retain serviceable hearing. 115:1078–1086, 2011)| false
MousaviSHKanoHFarajiAHGandeAFlickingerJCNiranjanA: Hearing preservation up to 3 years after Gamma Knife radiosurgery for Gardner-Robertson class I patients with vestibular schwannomas. Neurosurgery76:584–5912015
MousaviSH, KanoH, FarajiAH, GandeA, FlickingerJC, NiranjanA, : Hearing preservation up to 3 years after Gamma Knife radiosurgery for Gardner-Robertson class I patients with vestibular schwannomas. 76:584–591, 2015)| false