Bilateral Electrical Stimulation of a Congenitally-deaf Ear and of an Acquired-deaf Ear

Abstract

Two identical multichannel intracochlear prostheses were implanted in the same patient. The first prosthesis, implanted in the congenitally-deaf right ear, elicited clear sound perception but no speech recognition. After 2 years, a second prosthesis, implanted in the acquired-deaf left ear, enabled the patient to understand speech without lip-reading. Brainstem and middle-latency evoked potentials were similar with electrical stimulation of both ears and resembled those evoked by acoustic stimuli in subjects with normal hearing. Cortical electric and magnetic responses differed for right- and left-sided electrical stimulation suggesting that stimulation of the congenitally-deaf ear elicited an abnormal activation of the auditory cortex. These results suggest that only cortical responses were affected by the different histories of deafness of the ears.

Bilateral cochlear implants: a way to optimize auditory perception abilities in deaf children?

“…Bilateral CI has been previously reported only sporadically in the literature [3][4][5]. Recent experience with bilaterally implanted adult patients have shown a significant improvement in auditory capabilities, especially those related to sound localization and speech discrimination in background noise [6][7][8][9].…”

Pitfalls in the management of monaural deafness

“…Results in bilaterally, postlingually deaf patients indicate that if auditory deprivation occurs after language acquisition, the auditory evoked potentials can re-normalise upon electrical stimulation, even after a very long period of sensory deprivation. 10,11 This emphasises the importance of speech stimulation within a critical period, in order to develop plasticity of the central auditory and speech systems. Thus, our patient's absence of speech stimulation to the innervated auditory cortex, due to her very early deafness in the CI ear, may have interfered with cortical plasticity and contributed to her poor CI outcome.…”

A Case Study of a 4-Year-Old Perilingual Deaf Child Implanted with an Ineraid Multichannel Cochlear Implant1

“…The cochlea was patent and recordings of the EABR were reproducible and similar to EABR of our Ineraid-implanted adolescent and adult patients who have regained their ability to understand free running speech without lip reading [5,[7][8][9][10]. Electrical equivalents of acoustically evoked (ABR) waves Il-V could be easily identified in the recordings ( fig.…”