Abstract

Failure to correctly identify the anatomical landmarks of cochlear implantation (CI) challenges surgical success in conventional cochlear implantat surgery (CCIS). It seems that the use of the navigation system (NS) in CI can reduce the damage to the cochlear structures, also be effective in finding the correct location of the round window, especially in cases of anatomical differences, repeated surgeries and congenital defects. This study was aimed to determine evaluation of NS accuracy in cochlear implant surgery (CIS). In this cross-sectional survey, 20 patients who were candidates for CCIS and another 20 using the NS method were examined. First, mastoidectomy was performed, and then the correct location of CI was determined by CCIS and NS. Finally, the distance deviations of two methods were recorded. The mean (standard deviation) and minimum anatomical distance difference of CCIS and NS for the following locations were as follows: Facial nerve in the facial recess= 3.42±1.14 mm and 1.8 mm; Horizontal semi-circular canal= 2.90±1.02 mm and 1.10 mm; Pyramidal process = 3.16±1.55 mm and 1.40; mm; Round window membrane= 3.28±1.76 mm and 1.2 mm; CI location= 3.9±1.38 mm and 1.13 mm. Also, the difference in the mean duration of surgery by CCIS (73.50±20.72) mm and NS (96.25±14.59) mm was significant (P=0.001). The deviation distance for CCIS and NS was more than the expected value (1 mm), which seems that NS did not have enough accuracy to detect the anatomical landmarks of CIS.