KOKLEAR İMPLANT KULLANICILARINDA ELEKTROT NÖRON ARAYÜZEYİNİN SPEKTRAL ÇÖZÜNÜRLÜK VE KONUŞMA ANLAŞILIRLIĞINA ETKİSİNİN DEĞERLENDİRİLMESİ

Abstract

In this study, it was aimed to compare the spectral resolution abilities and speech perception of cochlear implant (CI) users with and without inner ear anomalies (IEM) and to investigate the relationship between spectral resolution and speech perception in noise by determining the electrode insertion depth, which is one of the factors affecting the electrode neuron interface. In this study there were 14 CI users with normal inner ear anatomy and 23 CI users with IEM and the age range was 6 to 12 years old. Participants' spectral resolution skills were evaluated using the Spectro-Temporal Modulated Ripple Test (SMRT), and their speech perception skills were evaluated using the Hearing in Noise Test-Children (HINT-C). In order to obtain information about the electrode-neuron interface, angular insertion depth was calculated using the 'cochlear view' method from intraoperative X-RAY. The Auditory Behavior in Everyday Life (ABEL) questionnaire was administered to parents of CI users to evaluate their children's auditory behaviors in daily life environments. Our study reveals that CI users with normal cochlea have better speech perception in quiet and noise, and spectral resolution skills than CI users with IEMs. While CI users with normal cochlea can understand speech perception at low signal-to-noise ratios in HINT-C quiet, NIpsilateralSFront and NFrontSFront conditions, CI users with IEMs need higher signal-to-noise ratios (p<0,001, p=0,008, p=0,015). There was no significant difference in the condition of NcontralateralSFront (p=0,224) between groups. In SMRT, it was observed that users with inner ear anomalies had lower spectral resolution scores compared to users with normal anatomy (p=0,035). Angular insertion depth was found to be higher in normal cochlea than in inner ear anomalies. (p<0.001). In addition, the placement depths of the FORM series electrodes, explicitly produced for inner ear anomalies, were compared with the users' test results. CI users with FORM24 electrodes had better results than CI users with FORM19. A moderate negative correlation was observed between angular insertion depth and HINT quiet (r=-0,43, p=0,002), NIpsilateralSFront(r=-0,50, p=0,001) and NFrontSFront(r=-0,37, p=0,01) conditions, and a positive moderate correlation was observed between SMRT scores (r=0,48, p=0,001). Angular insertion depth was found to predict speech perception scores in quiet and noise and SMRT scores. According to the total score and four subscales of the ABEL questionnaire, it was seen that the parental opinions of users with normal cochlea and users with inner ear anomalies were similar (p>0,05).To our knowledge, this study is the first to compare the HINT-C and SMRT test scores of CI users with normal cochlea and inner ear anomalies and highlight their relationship with the quality of the electrode-neuron interface.