Hearing Outcomes After Stereotactic Radiosurgery for Jugular Paraganglioma.

Neil S Patel, Michael J Link, Colin L W Driscoll, Bruce E Pollock, Christine M Lohse, Matthew L Carlson

Otology & Neurotology 2018 January

OBJECTIVE: To describe audiometric outcomes following stereotactic radiosurgery (SRS) for jugular paraganglioma (JP).

STUDY DESIGN: Retrospective review.

SETTING: Tertiary referral center.

PATIENTS: Patients with pretreatment serviceable hearing (American Academy of Otolaryngology-Head and Neck Surgery [AAO-HNS] Class A or B) and serial post-SRS audiometric follow-up who underwent Gamma Knife SRS for JP between 1990 and 2017.

INTERVENTION(S): Gamma Knife SRS.

MAIN OUTCOME MEASURES: Progression to nonserviceable hearing; correlation between baseline hearing and treatment parameters with audiometric outcomes.

RESULTS: Of 85 patients with JP who underwent SRS during the study period, 35 (66% female, median age 53) had pretreatment serviceable hearing and serial post-treatment audiometry available for review. Median tumor volume at the time of treatment was 7,080 mm, median cochlear point dose was 5.8 Gy (interquartile range [IQR] 4.1 to 7.3 Gy), and median marginal and maximum tumor doses were 16 and 32 Gy, respectively. After a median follow-up of 37 months (IQR 16 to 77 mo), the median change in pure-tone average and speech discrimination score in the treated ear was -1.2 dB HL/yr (IQR -4.5 to 0.3) and 0%/yr (IQR 0-3.5%), compared with 0.07 dB HL/yr (IQR -0.03 to 0.12) and 0 %/yr (IQR 0 to 0%) in the contralateral untreated ear. Seven patients developed nonserviceable hearing (AAO-HNS Class C or D) at a median of 13.2 months following SRS (IQR 4.8 to 24 mo). Among those who maintained serviceable hearing, median audiometric follow-up was 42 months (IQR 18 to 77 mo). The Kaplan-Meier estimated rates of serviceable hearing at 1, 3, and 5 years following SRS were 91%, 80%, and 80%, respectively. Sixty percent of patients with pulsatile tinnitus who underwent SRS experienced varying levels of symptomatic improvement following treatment.

CONCLUSION: The short- and intermediate-term risk of progression to nonserviceable hearing following SRS for JP is low. Data regarding the impact of cochlear dose from the vestibular schwannoma literature should not be freely applied to JP, since the impact of SRS parameters on hearing preservation seems to be less significant.