Auditory Neuropathy Spectrum Disorder, CI, HA, or Ear Plug?
Audiological management of children with auditory neuropathy spectrum disorder (ANSD) remains challenging. Runge et al (2011) hypothesized that due to impaired temporal processing in children with ANSD, contralateral acoustic input may interfere with the signal from the CI, and, therefore, speech perception may decline with amplification and may improve with occlusion.
Runge and colleagues (2011) evaluated nine children with ANSD who had received and worn a unilateral cochlear implant (CI) for at least a year—and who had contralateral aidable hearing (3 frequency pure tone average of less than or equal to 80 dB HL). They sought to answer the question of how to best treat the contralateral ear? They considered occluding/plugging the ear, hearing aid amplification, a second CI or leaving it alone. They measured speech perception with the Children’s Realistic Index for Speech Perception Junior (CRISP Jr, see Garadat and Litovsky, 2007). Plugging the ear was accomplished and verified using foam earplugs and by calculating the difference between the real-ear unaided response (REUR) and the real-ear occluded response (REOR).
In contrast to the hypothesis (see paragraph one), bimodal amplification (one hearing aid and one cochlear implant) in quiet provided statistically improved performance, as compared to the CI by itself. In noise, a significant bi-modal advantage was not demonstrated. The authors concluded children with ANSD and a unilateral CI may benefit from hearing aid amplification on the contralateral ear and hearing aid trials are recommended for appropriate candidates.
For More Information, References, and Recommendations
Garadat S, Litovsky RY. (2007) Speech Intelligibility in Free Field—Spatial Unmasking in Preschool Children. Journal of the Acoustical Society of America 121:1047-1055.
Picton TW. (2011) Auditory Neuropathy – When Time is Broke. Human Auditory-Evoked Potentials. Plural Publishing Inc.
Roche JP, Huang BY, Castillo M, Bassim MK, Adunka OF, Buchman CA. (2010) Imaging Characteristics of Children with Auditory Neuropathy Spectrum Disorder. Otology & Neurotology 31(5):780–788.