Can findings on routine audiometry predict the results of a formal cochlear implant candidacy evaluation?
Bottom line: Routine audiometric findings can be used to identify patients who are likely to meet CI candidacy upon formal testing.
Explore this issue:January 2017
Background: Although cochlear implantation benefits have been well described, it is clear that the technology is underutilized. One contributory factor is that there are no established criteria on routine office-based audiometry to assist audiologists, hearing instrument specialists, and otolaryngologists in their decisions on whether to refer patients for a formal CI evaluation.
Study design: Retrospective, observational, diagnostic study of the charts of 139 adult patients evaluated for implant candidacy at a tertiary care center from June 2008 through June 2013.
Setting: University of Wisconsin–Madison, School of Medicine and Public Health.
Synopsis: With regard to hearing loss pattern, 75 were downsloping, 56 were flat, and eight were considered other. Researchers found that 83.3% of patients with pure tones at or below 54.7 dB at 250 Hz would meet CI candidacy upon formal evaluation using AzBio sentences in quiet. Eighty-seven percent of patients who scored 30.2% or less correct in the monosyllabic word recognition test (MWRT) qualified for a CI according to Medicare criteria using Hearing in Noise Test (HINT) sentences, 81.5% of patients who scored 35.6% or less correct in the MWRT qualified using AzBio sentences in quiet, and 93.3% of hearing loss patients who scored 39.2% or less correct in the MWRT qualified using AzBio sentences with background noise.
For downsloping pattern patients, 71.4% who scored 30% or less correct in the MWRT qualified when using HINT sentences; for flat pattern patients, 96.7% of patients who scored 33% or less correct in the MWRT qualified. Ultimately, 102 participants qualified for implantation. Limitations included a study population of adult patients who had already been referred for a CI evaluation and use of a recorded voice in presenting monosyllabic words (See Figure 1).