2012 Volume 55 Issue 3 Pages 190-197
We investigated the relation between the hearing threshold and the age at cochlear implantation, duration of deafness, and cause of deafness in 45 adult long-term cochlear implant users. We compared the T level and C level, dynamic range, and speech perception between the group with a good hearing threshold (the good group) and the group with a poor hearing threshold (the poor group). The results were as follows.
1.A tendency towards a good hearing threshold was observed in cases with a duration of deafness of one year or less.
2.Significant differences in the C level and consonant perception scores were observed between the good group and the poor group.
3.The results suggested a high hearing threshold and low consonant perception scores in the poor group, because it was difficult to raise the C level and T level, and to widen the dynamic range.
4.The findings suggested the possibility that the degeneration of the auditory nerve fibers on the retrocochlear auditory pathway caused a high hearing threshold in the poor group.
5.The findings also suggested the possibility that a disturbed retrocochlear auditory pathway affected the hearing threshold and the consonant perception scores.
