Cochlear implants in single-sided deafness – clinical results of a Swiss multicentre study

Abstract

AIM OF THE STUDY: The aim of this multicentre, prospective, open, nonrandomised clinical trial was to demonstrate the clinical efficiency and outcomes of cochlear implants (CIs) in adult patients with post-lingual single-sided deafness (SSD).METHODS: A group of five left and five right SSD participants were investigated with various clinical tests and questionnaires before and 12 months after CI activation. Changes in hearing thresholds, speech understanding in noise, sound localisation, tinnitus (Tinnitus Handicap Inventory; THI), subjective hearing ability (Speech, Spatial and Qualities of Hearing Scale; SSQ), and quality of life (WHOQOL-BREF) were assessed. In addition, the preand postoperative results of the SSD patients were compared with an age-and gender-matched normal hearing control group. RESULTS: Surgery was uncomplicated in all patients. Two years after implantation, 9 of the 10 patients used their CI regularly for an average of more than 11 hours a day. A significant improvement in speech understanding in noise measured in the sound field using the Oldenburg sentence test could be demonstrated in the two situations in which patients with SSD experience the greatest difficulty: speech from the front and noise at the healthy ear, and speech to the implanted ear and noise from the front. The sound localisation test showed significant improvement of the mean localisation error and the root mean square error after CI activation. Furthermore, a significant reduction of the THI was measured, and the SSQ showed a significant improvement in the subscale speech comprehension and in the subscale spatial hearing. Also, quality of life measured with the WHOQOL-BREF showed a general improvement, which was significant in the global subscale. For this questionnaire, there was no significant difference between the normal-hearing control group and the patients after 12 months of CI use.CONCLUSION: This study confirmed the clinical benefit of cochlear implantation in patients with SSD. The significant improvement of speech understanding in noise, sound localisation, tinnitus perception, subjective hearing ability, and in particular the improved quality of life support the recommendation that patients with recently acquired SSD should be offered a CI. (Clinical trial registration number on clinicaltrial.gov: NCT01749592)

Short-term outcomes of cochlear implantation for single-sided deafness compared to bone conduction devices and contralateral routing of sound hearing aids—Results of a Randomised controlled trial (CINGLE-trial)

“…For the first time in 2008, Van de Heyning et al [ 5 ] reported a significant decrease in tinnitus distress (TQ) and tinnitus loudness (Visual Analogue Scale (VAS) score) following cochlear implantation in unilaterally deaf patients suffering from incapacitating tinnitus. Later, others reported beneficial results of electrical stimulation by cochlear implantation on tinnitus as well [ 17 , 20 , 31 , 38 , 39 ]. An important issue to be mentioned is the absence of a minimum level of tinnitus distress to be eligible for inclusion in our study.…”

“…However, the proportion of patients that opted for BCD or CROS after the trial period was not mentioned, and no objective outcomes of hearing performance were published from these satisfied patients. Likewise, SSD patients were offered a CI in a Swiss study if they had unsatisfactory benefit from a trial with CROS or BCD: forty-four of 54 study patients did not proceed to cochlear implantation [ 39 ]. Unfortunately, there were no results available from those patients who opted for BCD or CROS.…”

“…Unfortunately, there were no results available from those patients who opted for BCD or CROS. Of the ten patients that were implanted, only results with CI were published and not from the trial period with CROS or BCD [ 39 ]. Kurz et al [ 14 ] implemented the study design that was proposed at an international consensus meeting [ 1 ], and found that 16 of 34 patients decided not to opt for cochlear implantation after a trial period with BCD and CROS (3 weeks each).…”

Traitement de la surdité unilatérale par l’implant cochléaire

“…En 2019, une étude multicentrique suisse a été publiée avec une analyse de la performance auditive détaillée de 10 patients implantés avec surdité unilatérale. 13 Elle a montré une amélioration significative de la compréhension dans le bruit, surtout dans les situations les plus difficiles pour le patient. On retrouvait aussi un gain quand l'oreille saine est masquée par du bruit, ce qui n'est pas possible avec des systèmes pseudo-stéréophoniques.…”

“…11,14 Tous ces gains, mesurés et objectivables, se reflètent dans une amélioration substantielle de la qualité de la vie globale 13. Il est important de savoir que la performance auditive avec un implant cochléaire pour surdité unilatérale reste inférieure par rapport à celle d'un patient avec une audition normale.…”