The Study Of Molecule Pathogenesis And Curative Effect Of Cochlear Implantation Recipients

Cochlear implantation (CD is one of effective method for severe and profound sensory deafness. CI has been used successfully to restore hearing in more than 4000 deafness in China, but there is no systematical study on the etiological factors of these patients, especially on the molecule pathogenesis. Besides, the influence of various hereditary etiological factors on the curative effect of CI is not extremely definite. This study will evaluate the integrity of cochlear nerve and nervous pathway, and investigates the molecule pathogenesis of deafness. At the same time, we offer the hereditary deafness patients and their families the genetic counseling, in order to decrease the cases of hereditary deafness. We discuss the difference of curative effect between different hereditary deafness and control group. Part one: Evaluation of audiology and imageology data of patients before CIObjective To investigate the effect of preoperative audiology and imageology data in anticipating indication and contraindication of CI. Methods Retrospectively study the preoperative audiology and imageology data of CI recipients in our department. Results Of 246 cases, at least one of Audiological tests has auditory response, but 16 cases do not induce definite auditory response so that can not judge the integrity of the cochlear nerve and nervous pathway .There are 38 cases with inner ear malformation in CT and MRI films. There are one case with inner acoustic meatus narrow and one case with fibrous degeneration partially in Cochlea after trauma. 16 cases have no response to audiological test, and MRI films indicate that configuration of inner acoustic meatus and cochlear nerve is normal in 14 cases. Conclusion We can judge correctly by binding audiological tests with imageology data. Part two: Study of the molecule pathogenesis of deafness in CI recipientsObjective To analyze the molecular pathogenesis of deafness in 127 CI recipients. Methods The molecule pathogenesis of 127 CI recipients from our department was analyzed, including mtDNA A1555G mutation, PDS gene, GJB2 (Cx26) gene andGJB3 (Cx31) gene for mutations. Results: Among 127 deaf patients, 31 cases were found to have GJB2 mutation. Three patients were found to carry mtDNA A1555G mutation. Among 10 patients with large vestibular aqueduct, 9 cases were found to have mutation. One novel mutation, GJB2 235delC/598G>A was identified in this study. The GJB3 (Cx31) was the only gene without detecting any mutation, but with 4 kinds of polymorphism. Conclusions The first most frequently occurring mutations were found in the Cx26 (31/127, 24.4%).GJB2 gene mutations were the major cause for autosomal recessive non-syndromic hearing impairment (NSHI). Part three: The curative effect of CI in patients with autosomal recessive NSHI.Objective To analyze the curative effect of CI in patients with autosomal recessive NSHI, including GJB2 (Cx26) gene mutation and large vestibular aqueduct syndrome. Method The evaluations of curative effect include auditory threshold with CI. The postoperative outcomes of these cases with autosomal recessive NSHI were compared patients with negative results of screening of gene mutation (control group). Result The postoperative outcomes of CI with GJB2 (Cx26) gene mutation and LVAS had no significant difference in comparison with control group (P>0.05). Conclusion CI could be performed in the patients with GJB2 (Cx26) gene mutation and LVAS. Postoperative outcomes of hearing and speech in the patients with GJB2 (Cx26) gene mutation and LVAS were satisfied.PART FOUR: Complications and their management and analysis of contents of informed consent in CIObjective To study the complications and the management and sequelae of each complication encountered in 262 CI recipients. To study contents of informed consent of 262 CI recipients, and to design a new reasonable informed consent used for CI. Methods Retrospectively study the complications and the contents of informed consent of CI recipients in our department. Results There were 4 major surgical complications (e.g., persistent eardrum perforation, facial paralysis, leakage of cerebrospinal fluid with meningitis). There were 40 minor surgical complications, respectively. These complications were managed with conservative treatment or minor intervention. The 9 of 11 CI device complications have been managed withrevision or reimplantation. While the complications contents in the informed consents of the CI were not complete and normative. Conclusion CI is a relatively safe surgical operation. Most surgical complications are minor and can be treated with conservative treatment or minor surgical intervention. It is very important to choose patients according to the indication of CI. It is very important to normalize the contents and format of CI surgical informed consents.