ABSTRACT
Objective@#To discuss the benefit of using transmastoid slotted labyrinthotomy approach (TSLA) and customized electrode for common cavity deformity (CCD) patients, and to evaluate the audiological outcomes.@*Methods@#A retrospective analysis of the intraoperative monitoring data and postoperative auditory outcomes of 10 CCD cases who received cochlear implantation in Beijing Tongren Hospital,Capital Medical University from April 2016 to December 2017, was conducted using TSLA and customized electrod as a test group.At the same time, 10 cases of age and gender matched children with severe or severe sensorineural hearing loss and normal inner ear structures were recorded as a control group. Four questionnaires were collected from the two groupspre-operative, 6 months and 1 year after start-up. The Wilcoxon signed rank sum test was used to compare the scores of different time points. Rank sum test of two independent samples was used to compare the scores between different groups.@*Results@#None of the patients exhibited CSF leakage or facial paralysis after operation. The average impedance of 8 CCD children in the experimental group was below 5 kΩ. The total extraction rate of auditory neural response telemetry (ART) of all stimulating electrodes was 55% (33/60), and the amplitude of the electricity induced complex action potential (ECAP) of electrodes at different positions ranged from 50.69 to 170.3 μV.The average surgical time of the TSLA group was 46.4 min, shorter than the traditional approach.There was significant difference between the scores of pre-operative, 6 months and 1 year after start-up for the TSLA group(categories of auditory performance,CAP: 2.0 (2.0,3.0) vs. 4.0 (3.8,4.0) , Z=-3.109, P=0.002; speech intelligibility rating,SIR: 2.0 (2.0,2.3) vs. 3.0 (2.8,4.0) , Z=-2.952, P=0.003; meaningful use of speech scale,MUSS: 4.0 (3.3,6.0) vs. 9.0 (6.0,11.8) , Z=-3.421, P=0.001; meaningful auditory integration scale, MAIS or infant-toddler and meaningful auditory integration scale, IT-MAIS: 5.5 (3.8,9.0) vs. 15.5 (10.8,18.5) , Z=-3.522, P=0.000 for the latter two).In addition, The scores of the TSLA group were significantly worse than the control group at 6 months and 1 year after start-up.The high-resolution CT scan showed good adhesion of the electrodes without displacementone week and one year after surgery.@*Conclusions@#For CCD patients, TSLA and customized electrode is recommended due to lower surgical difficulty and post-operative risk, shortened surgical time; Intraoperative ART monitoring can be used to determine the integrity of the auditory pathway. Children with common cavity deformity have a longer period of auditory rehabilitation, and the individual differences in speech rehabilitation are significantly different, which is significantly worse than those with normal structure.
ABSTRACT
Encouraging results have been reported in implanted patients with cochlear malformations, but relevant information about results in the common cavity is not enough. This case study is to report postimplantation performance in a boy with common cavity inner ear malformation. The subject received a Nucleus 22-channel cochlear implant at the age of 34 months. Radiological assessments using CT and MRI revealed bilateral common cavity deformities. Twelve electrodes were inserted premeditatedly, and eleven electrodes were active in his pseudomonopolar mode map. A wide pulse width needed to be used because the T level was high, and facial twitching was present at the higher C level. Speech perception and speech-language evaluations were conducted at pre and postoperative 6-month intervals for up to 4 years. He showed limited sound response and could not perform the formal speech perception tests for initial several months. However, he was able to complete the Body-Parts and ESP tests (low version) at 1 postoperative year and achieved the score of 80% for NU-CHIPS at 2 years after implantation. His open-set word recognition ability has shown continuous improvement over time. PBK score was 80% on phonemes and 50% on words at 2 years, Common Phrases score was 90% at 3 years following implantation. He also developed age appropriate language skills after 3 years of implantation. This report demonstrates that this child could remarkably benefit from cochlear implant even with severe cochlear malformation.