OBJECTIVES: It has long been known that cochlear implantation may cause loss of residual hearing and vestibular function. Different insertion depths may cause varying degrees of intracochlear trauma in the apical region of the cochlea. The present study investigated the correlation between the insertion depth and postoperative loss of residual hearing and vestibular function. DESIGN: Thirty-nine adults underwent unilateral cochlear implantation. One group received a Med-El +Flex electrode array (24 mm; n = 4), 1 group received a Med-El +Flex electrode array (28 mm; n = 18), and 1 group received a Med-El +Flex electrode array (31.5 mm; n = 17). Residual hearing, cervical vestibular-evoked myogenic potentials, videonystagmography, and subjective visual vertical/horizontal were explored before and after surgery. The electrode insertion depth and scalar position were examined with high-resolution rotational tomography after implantation in 29 subjects. RESULTS: There was no observed relationship between the angular insertion depth (405° to 708°) and loss of low-frequency pure-tone average. Frequency-specific analysis revealed a weak relationship between the angular insertion depth and loss of hearing at 250 Hz (R= 0.20; p = 0.02). There was no statistically significant difference in the residual hearing and vestibular function between the +Flex and the +Flex electrode array. Eight percent of the cases had vertigo after surgery. The electrode arrays were positioned inside the scala tympani and not scala vestibuli in all subjects. In 18% of the cases, the +Flex electrode array was not fully inserted. CONCLUSIONS: The final outcome in residual hearing correlates very weakly with the angular insertion depth for depths above 405°. Postoperative loss of vestibular function did not correlate with the angular insertion depth or age at implantation. The surgical protocol used in this study seems to minimize the risk of postoperative vertigo symptoms.
OBJECTIVES: It has long been known that cochlear implantation may cause loss of residual hearing and vestibular function. Different insertion depths may cause varying degrees of intracochlear trauma in the apical region of the cochlea. The present study investigated the correlation between the insertion depth and postoperative loss of residual hearing and vestibular function. DESIGN: Thirty-nine adults underwent unilateral cochlear implantation. One group received a Med-El +Flex electrode array (24 mm; n = 4), 1 group received a Med-El +Flex electrode array (28 mm; n = 18), and 1 group received a Med-El +Flex electrode array (31.5 mm; n = 17). Residual hearing, cervical vestibular-evoked myogenic potentials, videonystagmography, and subjective visual vertical/horizontal were explored before and after surgery. The electrode insertion depth and scalar position were examined with high-resolution rotational tomography after implantation in 29 subjects. RESULTS: There was no observed relationship between the angular insertion depth (405° to 708°) and loss of low-frequency pure-tone average. Frequency-specific analysis revealed a weak relationship between the angular insertion depth and loss of hearing at 250 Hz (R= 0.20; p = 0.02). There was no statistically significant difference in the residual hearing and vestibular function between the +Flex and the +Flex electrode array. Eight percent of the cases had vertigo after surgery. The electrode arrays were positioned inside the scala tympani and not scala vestibuli in all subjects. In 18% of the cases, the +Flex electrode array was not fully inserted. CONCLUSIONS: The final outcome in residual hearing correlates very weakly with the angular insertion depth for depths above 405°. Postoperative loss of vestibular function did not correlate with the angular insertion depth or age at implantation. The surgical protocol used in this study seems to minimize the risk of postoperative vertigo symptoms.
Authors: Manuel Christoph Ketterer; A Aschendorff; S Arndt; I Speck; A K Rauch; R Beck; F Hassepass Journal: Eur Arch Otorhinolaryngol Date: 2020-10-22 Impact factor: 2.503
Authors: Paul Van de Heyning; Peter Roland; Luis Lassaletta; Sumit Agrawal; Marcus Atlas; Wolf-Dieter Baumgartner; Kevin Brown; Marco Caversaccio; Stefan Dazert; Wolfgang Gstoettner; Rudolf Hagen; Abdulrahman Hagr; Greg Eigner Jablonski; Mohan Kameswaran; Vladislav Kuzovkov; Martin Leinung; Yongxin Li; Andreas Loth; Astrid Magele; Robert Mlynski; Joachim Mueller; Lorne Parnes; Andreas Radeloff; Chris Raine; Gunesh Rajan; Joachim Schmutzhard; Henryk Skarzynski; Piotr H Skarzynski; Georg Sprinzl; Hinrich Staecker; Timo Stöver; Dayse Tavora-Viera; Vedat Topsakal; Shin-Ichi Usami; Vincent Van Rompaey; Nora M Weiss; Wilhelm Wimmer; Mario Zernotti; Javier Gavilan Journal: Front Surg Date: 2022-03-24
Authors: Magdalena Sosna-Duranowska; Grazyna Tacikowska; Elzbieta Gos; Anna Krupa; Piotr Henryk Skarzynski; Henryk Skarzynski Journal: Front Neurol Date: 2021-05-21 Impact factor: 4.003