Iranian Journal of Otorhinolaryngology

Iranian Journal of Otorhinolaryngology

Effect of electrode insertion depth on word recognition in MED-EL (COMBI 40+) cochlear implant users.

Authors
M Ghasemi
Nasrin Rasta
Mohamadtaghi Shakeri
Mohamadreza talea
Rahim Ghanbari
Hamid Taeraninejad
Effat Daroobord
10.22038/ijorl.2005.28686
Abstract
Electrode arrays are inserted only partially into the cochlea, typically 22-30mm depending on the state of the cochlea and prosthesis type. This study aimed to investigate the effect of electrode insertion depth on word recognition in a group of 10 implanted patients using the MED-EL (COMBI 40+) multichannel cochlear implant devices, who had at least six months of "Auditory-verbal Training"experiences following implant surgery.
Material and Method: To determine the effect of electrode insertion depth on word recognition score three different depth levels were simulated, including: full insertion depth (3):(2) insertion depth and 1 insertion depth. While the overall spectral band 3
width was preserved, word recognition score was measured on ten bisyllabic words immediately after each levels.
Result: The results showed that word recognition scores decreased dramatically by turning off the apical third of electrode array. We believe that these results indicate that: Conclusion: Most speech recognition could be providing by the last(Apical) third of the cochlea.
1-There are useful neurostructures for speech recognition beyond the second turn of the