Changes in Tinnitus by Cochlear Implantation: A Parametric Study of the Effect of Single-Electrode Stimulation

Cochlear implant in tinnitus management

PURPOSE OF REVIEW

To evaluate whether cochlear implantation can mitigate tinnitus perception and its discomfort among patients with severe-to-profound hearing loss, in order to provide an answer on a possible treatment for a health condition with high prevalence and impact on quality of life.

RECENT FINDINGS

Tinnitus can develop after peripheral hearing loss and is associated with altered auditory processing. It does not only involve auditory structures but also aberrant neural activity and interaction with other regions of the Central Nervous System associated with emotion, attention, anguish, memory and motor activity.

SUMMARY

Recent studies investigated the changes in tinnitus perception among patients who underwent cochlear implantation and demonstrated a postoperative decrease. Hence, patients with severe-to-profound sensorineural hearing loss and tinnitus are likely to benefit from cochlear implantation.

Systematic Review on Intra- and Extracochlear Electrical Stimulation for Tinnitus

Several electrical stimulation patterns of the auditory nerve have been described for tinnitus relief, but there is no consensus on the most effective stimulation pattern. Therefore, we aim to systematically review the literature on the effect of intra- and extracochlear electrical stimulation patterns as a treatment option for patients with tinnitus. Only studies on intra- and extracochlear electrical stimulation for patients with tinnitus were included if the stimulation used did not concern standardized CI stimulation patterns to primarily rehabilitate hearing loss as intervention. A total of 34 studies met the inclusion criteria, with 10 studies (89 patients) on intracochlear electrical stimulation and 25 studies on extracochlear electrical stimulation (1109 patients). There was a high to medium risk of bias in 22 studies, especially due to lack of a non-exposed group and poor selection of the exposed group. All included studies showed subjective tinnitus improvement during or after electrical stimulation, using different stimulation patterns. Due to methodological limitations and low reporting quality of the included studies, the potential of intra- and extracochlear stimulation has not been fully explored. To draw conclusions on which stimulation patterns should be optimized for tinnitus relief, a deeper understanding of the mechanisms involved in tinnitus suppression is needed.