Cochlear implantation after radiosurgery for vestibular schwannoma.

Abstract

OBJECTIVE:

The object of this study was to ascertain outcomes of cochlear implantation (CI) following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS).

METHODS:

The authors conducted a retrospective chart review of adult patients with VS treated with SRS who underwent CI between 1990 and 2019 at a single tertiary care referral center. Patient demographics, tumor features, treatment parameters, and pre- and postimplantation audiometric and clinical outcomes are presented.

RESULTS:

Seventeen patients (18 ears) underwent SRS and ipsilateral CI during the study period. Thirteen patients (76%) had neurofibromatosis type 2 (NF2). Median age at SRS and CI were 44 and 48 years, respectively. Median time from SRS to CI was 60 days, but notably, 4 patients underwent SRS and CI within 1 day and 5 patients underwent CI more than 7 years after SRS. Median marginal dose was 13 Gy. Median treatment volume at the time of SRS was 1400 mm3 (range 84-6080 mm3, n = 15 patients). Median post-CI PTA was 28 dB HL, improved from 101 dB HL preoperatively (p < 0.001). Overall, 11 patients (12 ears) exhibited open-set speech understanding. Sentence testing was performed at a median of 10 months (range 1-143 months) post-CI. The median AzBio sentence score for patients with open-set speech understanding was 76% (range 19%-95%, n = 10 ears). Two ears exhibited Hearing in Noise Test (HINT) sentence scores of 49% and 95%, respectively. Four patients achieved environmental sound awareness without open-set speech recognition. Two had no detectable auditory percepts.

CONCLUSIONS:

Most patients who underwent CI following SRS for VS enjoyed access to sound at near-normal levels, with the majority achieving good open-set speech understanding. Implantation can be performed immediately following SRS or in a delayed fashion, depending on hearing status as well as other factors. This strategy may be applied to cases of sporadic or NF2-associated VS.

ABBREVIATIONS:

AAO-HNS = American Academy of Otolaryngology-Head and Neck Surgery; ABI = auditory brainstem implant; CI = cochlear implantation; CN = cranial nerve; CNC = consonant-nucleus-consonant; CPA = cerebellopontine angle; EPS = electrical promontory stimulation; ESA = environmental sound awareness; HINT = Hearing in Noise Test; IAC = internal auditory canal; NF2 = neurofibromatosis type 2; OSP = open-set speech perception; PTA = pure tone average; SRS = stereotactic radiosurgery; VS = vestibular schwannoma; WRS = word recognition score.

• Authors: Neil S Patel, Matthew L Carlson, Michael J Link, Brian A Neff, Jamie J Van Gompel, Colin L W Driscoll
• Journal: Journal of neurosurgery (J Neurosurg) Vol. 135 Issue 1 Pg. 126-135 (07 01 2021) ISSN: 1933-0693 [Electronic] United States
• PMID: 34250789 (Publication Type: Case Reports, Journal Article)

Topics

• Adolescent
• Adult
• Aged
• CREST Syndrome (complications)
• Cochlear Implantation
• Cochlear Nerve (diagnostic imaging, physiopathology)
• Female
• Hearing Loss, Sensorineural (etiology, rehabilitation)
• Hearing Loss, Unilateral (etiology, rehabilitation)
• Hearing Tests
• Humans
• Male
• Middle Aged
• Neurofibromatosis 2 (complications)
• Neuroma, Acoustic (complications, diagnostic imaging, rehabilitation, surgery)
• Radiosurgery
• Retrospective Studies
• Speech Perception
• Treatment Outcome
• Young Adult