Abstract
BACKGROUND: Patients with a cochlear implant (CI) should be evaluated for a new speech processor every 6 years. The aim of this analysis was to assess the subjective and audiological benefit of upgrades. METHODS: Speech understanding and subjective benefit were analyzed in 99 patients with the old and the new speech processor after 4 weeks of wearing. Speech understanding was assessed using the Freiburg monosyllabic test in quiet (FBE) at 65 dB and 80 dB, and the Oldenburg Sentence Test (OLSA) at 65 dB noise with adaptive speech sound level. The Abbreviated Profile of Hearing Aid Benefit (APHAB) was used to assess subjective hearing impairment, and the Audio Processor Satisfaction Questionnaire (APSQ) was used to assess subjective satisfaction. RESULTS: The speech processor upgrade resulted in a significant improvement of speech understanding in quiet at 65 dB (mean difference 8.9 ± 25.9 percentage points, p < 0.001) and 80 dB (mean difference 8.1 ± 29.7 percentage points, p < 0.001) and in noise (mean difference 3.2 ± 10.7 dB signal-to-noise ratio [S/N], p = 0.006). Using the APHAB, a significant improvement (mean difference 0.07 ± 0.16, p < 0.001) in hearing impairment was demonstrated in all listening situations. The APSQ showed significantly higher patient satisfaction with the new speech processor (mean difference 0.42 ± 1.26, p = 0.006). A comparative assessment of the benefit based on subjective and speech audiometric results identified a proportion of patients (35-42%) who subjectively benefited from the upgrade but had no measurable benefit based on speech audiometry. CONCLUSION: There was a significant improvement in audiologically measurable and subjectively reflected speech understanding and patient satisfaction after the upgrade. In patients with only a small improvement in audiologically measurable speech understanding, the subjective benefit should also be assessed with validated measurement instruments in order to justify an upgrade to the payers in the health sector.