Background and objective:The size of the cochlea varies a lot among the human population bringing the necessity for electrode arrays to be available in various lengths irrespective of the cochlear implant(CI)brand.Thi...Background and objective:The size of the cochlea varies a lot among the human population bringing the necessity for electrode arrays to be available in various lengths irrespective of the cochlear implant(CI)brand.This research software helps in the estimation of the patient’s cochlear duct length(CDL)which is then used for the simulation of the correct length electrode array matching the patient’s cochlear size and as well in getting the patient specific cochlear frequency map.Methods:Visual Studio Express 2012 for Windows Desktop is used in the architecture of this research software.The basal turn diameter of the cochlea("A"value)needs to be measured from the pre-operative computed tomography(CT)image of the patient’s temporal bone.This"A"will be taken as the input for the CDL equations proposed by Alexiades et al for estimating the CDL along the basilar membrane for various insertion depths.Greenwood’s equation is then used in combination with the CDL for the full length of the cochlea in getting the patient specific frequency map.Results:The research software with the help of the"A"value as input,with few button clicks,gives the patient specific CDL for various insertion depths and the Greenwood’s frequency map.The users have the choice to select any electrode array of their choice and place it under the frequency map to see how good it fits to that particular patient’s cochlea.Also,given the possibility to drag and move the electrode array picture to mimic the post-operative actual electrode insertion depth.Conclusions:This research software simplifies the overall process of CDL estimation and in getting the patient specific cochlear frequency map.The clinicians get the chance to simulate placing the various electrode array lengths in patient cochlea in identifying the best fit electrode.This could help in pushing the CI field into the concept of individualized CI electrode array solution that ultimately benefits the patients.展开更多
A three-dimensional inner stereocilium model is established by PATRAN. According to the relevant data, the corresponding pressure is applied to one side of the inner stereocilia. The top displacement of the inner ster...A three-dimensional inner stereocilium model is established by PATRAN. According to the relevant data, the corresponding pressure is applied to one side of the inner stereocilia. The top displacement of the inner stereocilia along the cross section of the basilar membrane （the x-displacement） is similar to the available data in the literature, which verifies the correctness of the model. Based on Castigliano＇s theorem, the displacement of a single stereocilium is achieved under the inverted triangle force. The results are in good agreement with the data obtained from the finite element （FE） model, which confirms the validity of the formula. With the FE model, the effects of the movement of the hair cells and fluid in the cochlear duct on the x-displacements of the inner stereocilia are studied. The results show that the movement of the hair cells affects the x-displacements of the inner stereocilia, especially for the shortest stereocilium, and the fluid in the cochlear duct affects the x-displacements of the inner stereocilia, especially for the middle stereocilium. Moreover, compared with the effects of the hair cells on the stereocilia, the effect of the cochlear duct fluid is greater.展开更多
With cochlear implantation(CI)being the standard of care for profoundly deaf cases,more and more patients with low frequency residual hearing are currently being treated with CI.In view of preserving the residual hear...With cochlear implantation(CI)being the standard of care for profoundly deaf cases,more and more patients with low frequency residual hearing are currently being treated with CI.In view of preserving the residual hearing,the ultimate aim of both the surgeons and the CI companies is to achieve zero-degree of electrode insertion trauma.Variations in the size and shape of cochlea,cross-sectional dimensions of ST,electrode insertion techniques with and without metal stylet rod and the experience level of the operating surgeons,all play a role in the electrode array related insertion trauma.An effective electrode design must include flexible array to accommodate the cochlear shape variation,electrode with variety of array lengths to support the concept of cochlear size specific electrode array and finally smaller cross-sectional dimensions of electrode array in matching the cross-sectional dimensions of ST.As per published reports,FLEX electrode array design offers minimal degree of electrode insertion trauma along with the possibility of patient specific electrode array length matching their cochlear size.Looking at the cross-sectional dimensions of FLEX electrode array along with its volume,it appear to be highly safe to the cochlea by not taking too much volume inside the ST.To offer additional support,otological pre-planning software tool like OTOPLAN is now clinically available in measuring the cochlear size in finding the best electrode array match along with the possibilities of anatomy based post-operative speech processor fitting.展开更多
文摘Background and objective:The size of the cochlea varies a lot among the human population bringing the necessity for electrode arrays to be available in various lengths irrespective of the cochlear implant(CI)brand.This research software helps in the estimation of the patient’s cochlear duct length(CDL)which is then used for the simulation of the correct length electrode array matching the patient’s cochlear size and as well in getting the patient specific cochlear frequency map.Methods:Visual Studio Express 2012 for Windows Desktop is used in the architecture of this research software.The basal turn diameter of the cochlea("A"value)needs to be measured from the pre-operative computed tomography(CT)image of the patient’s temporal bone.This"A"will be taken as the input for the CDL equations proposed by Alexiades et al for estimating the CDL along the basilar membrane for various insertion depths.Greenwood’s equation is then used in combination with the CDL for the full length of the cochlea in getting the patient specific frequency map.Results:The research software with the help of the"A"value as input,with few button clicks,gives the patient specific CDL for various insertion depths and the Greenwood’s frequency map.The users have the choice to select any electrode array of their choice and place it under the frequency map to see how good it fits to that particular patient’s cochlea.Also,given the possibility to drag and move the electrode array picture to mimic the post-operative actual electrode insertion depth.Conclusions:This research software simplifies the overall process of CDL estimation and in getting the patient specific cochlear frequency map.The clinicians get the chance to simulate placing the various electrode array lengths in patient cochlea in identifying the best fit electrode.This could help in pushing the CI field into the concept of individualized CI electrode array solution that ultimately benefits the patients.
基金supported by the National Natural Science Foundation of China(Nos.11272200 and 11572186)
文摘A three-dimensional inner stereocilium model is established by PATRAN. According to the relevant data, the corresponding pressure is applied to one side of the inner stereocilia. The top displacement of the inner stereocilia along the cross section of the basilar membrane （the x-displacement） is similar to the available data in the literature, which verifies the correctness of the model. Based on Castigliano＇s theorem, the displacement of a single stereocilium is achieved under the inverted triangle force. The results are in good agreement with the data obtained from the finite element （FE） model, which confirms the validity of the formula. With the FE model, the effects of the movement of the hair cells and fluid in the cochlear duct on the x-displacements of the inner stereocilia are studied. The results show that the movement of the hair cells affects the x-displacements of the inner stereocilia, especially for the shortest stereocilium, and the fluid in the cochlear duct affects the x-displacements of the inner stereocilia, especially for the middle stereocilium. Moreover, compared with the effects of the hair cells on the stereocilia, the effect of the cochlear duct fluid is greater.
文摘With cochlear implantation(CI)being the standard of care for profoundly deaf cases,more and more patients with low frequency residual hearing are currently being treated with CI.In view of preserving the residual hearing,the ultimate aim of both the surgeons and the CI companies is to achieve zero-degree of electrode insertion trauma.Variations in the size and shape of cochlea,cross-sectional dimensions of ST,electrode insertion techniques with and without metal stylet rod and the experience level of the operating surgeons,all play a role in the electrode array related insertion trauma.An effective electrode design must include flexible array to accommodate the cochlear shape variation,electrode with variety of array lengths to support the concept of cochlear size specific electrode array and finally smaller cross-sectional dimensions of electrode array in matching the cross-sectional dimensions of ST.As per published reports,FLEX electrode array design offers minimal degree of electrode insertion trauma along with the possibility of patient specific electrode array length matching their cochlear size.Looking at the cross-sectional dimensions of FLEX electrode array along with its volume,it appear to be highly safe to the cochlea by not taking too much volume inside the ST.To offer additional support,otological pre-planning software tool like OTOPLAN is now clinically available in measuring the cochlear size in finding the best electrode array match along with the possibilities of anatomy based post-operative speech processor fitting.
