Speech perception performance for 100 post-lingually deaf adults fitted with Neurelec cochlear implants: Comparison between Digisonic^® Convex and Digisonic^® SP devices after a 1-year follow-up

Abstract

Conclusion: Patients implanted with the Digisonic^® SP device showed better identification scores than those implanted with the Convex device, with skills continuing to improve over a longer time period. Technological improvements were beneficial in terms of speech perception in quiet. Objective: To compare speech perception skills for post-lingually deaf patients implanted with a previous Neurelec device, the Digisonic^® Convex, with those implanted with a more recent one, the Digisonic^® SP, which provides more electrodes and a faster stimulation rate. Methods: This was a retrospective study of 100 implanted patients, 45 with the Digisonic^® Convex implant and 55 with the Digisonic^® SP. Speech perception (dissyllabic words and sentences, in open set) was evaluated until 1 year after implantation. Results: Patients fitted with the Digisonic^® SP implant showed significantly better scores after 3, 6, and 12 months (mean scores: 53%, 62%, and 68% for words; 58%, 69%, and 75% for sentences) than those fitted with the Convex implant (34%, 42%, and 43% for words; 38%, 59%, and 51% for sentences). The improvement in speech perception after implantation for SP patients continued throughout the 12 months for words and 6 months for sentences, versus 6 months for words and 3 months for sentences for Convex patients.

Keywords::

• Outcome
• longitudinal
• surgery
• tonotopic mapping
• coding strategy
• electrodes

Acknowledgments

We want to thank one of the reviewers for his technical comments and experimentation ideas that gave new insights to our discussion. We are also especially grateful to Trevor Agus for his valuable comments.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.