Evaluation Of Electrode Morphology For Patients With Sensitive Deafness In Cochlear Implant By Means Of Multislice CT High Resolution Scanning

Objective:To evaluate the electrode location,shape and implantation in patients with multi-channel cochlear implants by Multislice CT High Resolution Scanning with the use of three-dimensional reconstruction.To explore the influencing factors of electrode angular insertion depth,relationship between electrode-to-modiolus distance and threshord of hearing reaction(THR).Methods: Twenty-nine cochlear implant(MED-EL)recipients in No.1 Hospital of China Medical University from January 2015 to October 2017,were involved in this study.Among them a total of 33 ears were included;20 males and 9 females,the left ear was implanted with 6 and the right ear were 27 implanted,aged from 8 months to37 years old,with an average age of 6 years.One week after the operation,MSCT and three-dimensional reconstruction of inner ear were performed in all of the 29 implanted patients.The images were sent to philips workstation to observe the location,shape and implantation of the electrodes.To measurure the angular insertion depth,linear insertion depth of the electrode,the diameter and perimeter of the cochlea and the electrode-to-modiolus distance.The patient's Hearing Threshold(THR)was reported after the device was switched on.SPSS22.0 software package was used for independent sample t-test or u-test,pearson correlation analysis and linear regression analysis test level: ? = 0.05,P <0.05 was statistically significant.Results: All the electrodes of 33 ear were implanted.The number of implanted electrodes was 12 pairs.The electrode position was abnormally 3 ears,and 6 pairs of electrode pairs were abnormal(not at the scala tympani).There was no significant difference in the implantation depth of the electrode between the implant ear and the age.The difference in depth of implantation between the male and the females was statistically significant(t = 2.516,P <0.05).Angular implantation depth and linear implant depth(LID)were positively correlated(R2 = 0.328,P <0.01).The depth of electrode implantation was inversely correlated with the diameter(A)and circumference of the basal turn(R2 = 0.436,0.275,P <0.05).The regression equation of angle implant depth,linear implant depth and cochlear baseplate diameter was Y =725.863 + 20.317X1-67.537X2(X1 is the depth of linear implantation and X2 is thediameter of cochlear bottom rotation),P <0.001 was statistically significant significance.The distance between the implant electrode and the cochlear axis was positively correlated with the THR(r = 0.113,P <0.05).Conclusion:Ear multi-slice spiral CT high-resolution scanning and three-dimensional reconstruction after cochlear implant is an effective evaluation method.The depth of implantation was significantly related to the size of the cochlea and the linear insertion depth.Cochlear rotation diameter,linear implant depth fitted multivariate linear regression equation of the electrode angle implantation depth has a certain effect.It is of certain reference value for the formulation of clinical surgical plans and the choice of electrode materials.The distance from the implant electrode to the cochlear axis was positively correlated with THR.