[Psychophysical data and speech comprehension after 2 years with the Clark/Nucleus prosthesis].

Psychophysical data such as threshold and comfort levels indicate an extensive preservation of auditory nerve fibers. Changes of these data can point to increasing damage of nerve fibres due to long-term electrical stimulation or to obliteration of the cochlea when an intracochlear system is used. Unfavourable levels indicate negative influence on speech comprehension. The psychophysical data and the speech comprehension of 10 patients fitted with a Clark/NUCLEUS cochlear implant in the last 2 years have been analysed. During this period of time the threshold and comfort levels remained almost stable, whereas speech comprehension is still increasing, though to a lesser extent, after 2 years with the implant. These results indicate that the patients suffer neither an increasing destruction of auditory nerve fibres nor severe intracochlear changes.