OBJECTIVE: The purpose of this study is to report surgical skills for CI cases with modiolus ossification and to investigate the relation between post-operational electroneurophysilogical test result and speech recognition result. Further more, we also attempt to confirm indications for CI in this specific population. METHOD: Based on temporal bone HRCT, 7 subjects were identified as modiolus ossification from 101 cases with cochlear ossification. Modiolus ossification is confirmed by CT scan if CT value in modiolus reaches or exceeds 900 HU with the exception of congenital modiolus ossification or modiolus seal off. Electroneurophysiological test was conducted intra- and pos-operationally speech tests were applied for 7 subjects. RESULT: Normal impedance value was observed by intro-operational measurement in 7 subjects. EABR test was conducted and negtive response was observed in only 1 subject, while other 6 subjects were confirmed with atypical EABR waves which were observed in apical and middle turn region. Hearing threshold test (in sound field) was applied, no auditory response was recorded for the subject without EABR waveform, while hearing threshold in average for the other 6 subjects was 75 dB. Results of speech tests (Mandarin) were followed as 0 for the one without EABR wave, while 100% (simple finals test) and 30% (simple initials test) for the other 6 subjects. CONCLUSION Optimal multichannel CI surgery that inserting and locating electrode array spirally is very frequently interrupted by ossification,which was indentified with atypical EABR wave and relative poor speech recognition results, especially in modiolus ossification case. A post-operative negative EABR response may indicate surgical failure following cochlear implantation.
Adolescent ; Adult ; Child ; Child, Preschool ; Cochlea ; pathology ; Cochlear Implantation ; Evoked Potentials, Auditory, Brain Stem ; physiology ; Female ; Humans ; Infant ; Male ; Middle Aged ; Ossification, Heterotopic ; surgery ; Postoperative Period ; Young Adult

OBJECTIVE: To summarize methods on diagnosis of congenital cochlear nerve canal (CNC) stenosis or atresia and to report results of post-operation such as auditory electrophysiological test and speech test. METHOD: Based on temporal bone HRCT and internal acoustic canal MRI, 27 bilateral congenital CNC stenosis/bony atresia cases were distinguished from 3 700 CI cases. Unilateral cochlear implantations were conducted above 27 cases. Post-operation tests such as auditory nerve response telemetry, EABR test, hearing threshold in sound field and speech recognition test were applied in the cases above. RESULT: Incidence of CNC stenosis/bony atresia was observed at 0.73% (27 in 3700 CI cases). Impedance values were in the normal range accounting for 27 cases. Intro operative auditory nerve response telemetry were conducted accounting for 21 cases while 6 cases which were implanted with Combi40 + were not available for this test. Atypical ART response wave was observed for 14 cases, while no response for 7 cases. EABR test was completed in 27 cases within post-operation during 3 months and atypical EABR was identified in all cases. Hearing threshold in sound field was confirmed at 75 dB which was the average value of 500 Hz,1000 Hz,and 2000 Hz in all 27 cases. Speech recognition test result reached to both 65% (21 cases, simple finals test) and fewer than 10% (21 cases, simple initials test). CONCLUSION By temporal bone HRCT pre-operation, CNC stenosis/bony atresia can be diagnosed. According to both relatively poor auditory and speech test results, further research and discussion are requisite to identify CI indication among the cases above.
Child ; Child, Preschool ; Cochlear Implantation ; Cochlear Nerve ; abnormalities ; Constriction, Pathologic ; Female ; Humans ; Infant ; Male ; Treatment Outcome

OBJECTIVE: To review the classification of cochlear modiolus deficiency and decision on surgical approach for above case,in order to provide mastery for cochlear implant (CI) indication. METHOD: Basing on temporal bone HRCT pre-operation, CI subjects with modiolus deficiency were defined as following groups: (1) deficiency caused by cochlear dysplasia (Mondini malformation); (2) deficiency caused by dysplasia of cochlear and vestibule (Common cavity malformation); (3) deficiency caused by absence of internal acoustic meatus fundus (IP-III malformation). Three types of surgical approach were utilized: type I, electrode array was introduced through facial recess, enlarged the round window, type II, opened the surface of chchlea, electrode array was introduced through facial recess, fenestration on posterior promontory and then inserted around lateral wall of inner-cochlear cavity. type III, electrode array was introduce through fenestration of lateral semicircular canal and then placed close to the bony wall of common cavity. RESULT: One hundred and sixty-six cochlear modiolus deficiency cases were identified into 3 groups as following: 135 Mondini malformation cases into group a, 18 common cavity malformation cases into group b, and 13 IP-III malformation cases into group c. Surgical approach: type I were used in 136 cases (123 Mondini cases and 13 IP-III cases), while approach type II in 12 cases (12 Mondini cases), and approach type III in 18 cases (18 common cavity cases). Income post-operation of CI: For group a (Mondini malformation), post-activation mean hearing threshold in sound field was 65 dB, speech recognition score is 95% (single finals test) and 25% (signal initials test), while it was 80 dB, 60% and 0 for group b (Conmon cavity malformation), and it was 55 dB, 100% and 45% for group c (IP-III malformation). CONCLUSION The income of speech recognition score for cochlear modiolus deficiency was relatively poor, group b was worst and group c was best, while group a moderate.
Cochlea ; abnormalities ; surgery ; Cochlear Implantation ; methods ; Cochlear Implants ; Ear ; Ear, Inner ; abnormalities ; Female ; Humans ; Male ; Postoperative Period ; Round Window, Ear ; surgery ; Semicircular Canals ; surgery ; Speech Perception ; Temporal Bone ; Vestibule, Labyrinth ; abnormalities

Objective To find out the influence of different suffix vowel(abbreviation:SV) on the duration of/s/(a voiceless fricative) with acoustic detection method. Methods Two men and two women who were fluent in Mandarin Chinese were recruited in this study. The words included /s/and the suffix vowel /a/,/u/or/i/.The CSL4150 software from Kay Co. was used to analyze the words. Then we compared the durations of/s/when the suffix vowel was /a/,/i/and/u/,respectively. The influence of difference suffix vowel on the duration was exam_ined, and gender effects were also studied on the duration. ResuIts As a voiceless fricative, when the suffix vowel was /a/,the duration for males was 200. 2, and 276. 8 ms for females, respectively. When the suffix vowel was /i/, the duration for males was 218. 2, and 326. 5 ms for females, respectively. When the suffix vowel was /u/,the dura_tion for males was 214. 5, and 302. 9 ms for females, respectively. ConcIusion When the suffix vowel is different, the duration of stop, resistance and in number is different, and also affected by gender.

Objective To study the analysis of auditory rehabilitation outcomes of patients with cochlear nerve canal stenosis after cochlear implantation(CI).Methods A cohort of 30 patients with bilateral profound senso-rineural hearing loss who were diagnosed with cochlear neural canal stenosis by high-resolution CT were tested with evoked compound action potential (ECAP)and evoked auditory brainstem response (EABR)during and 3 ,6 , 9 months after CI.Audiometry in sound field was also assessed before and 3 ,6 ,9 months after CI.Among the co-hort,1 7 patients over 3 years old underwent postoperative speech recognition rate test.All the auditory rehabilita-tion outcomes were analyzed.Results ① For all 30 patients,there were no obvious differences of ECAP and EABR waveforms tested in 3,6 and 9 months after CI.②The thresholds in sound field in 3,6,9 months after CI were 65 ±8 dB HL,62 ±4 dB HL and 61 ±7 dB HL,respectively.The thresholds in sound field were significantly im-proved after than before CI (100 ±5 dB HL).③ The single vowel recognition rates of 17 patients in 3 ,6 and 9 months after CI were 55%±7%,56%±8% and 80%±4%,respectively.The single vowel recognition rate was significantly improved in 9 months after than before CI(52%±8%).The single consonant recognition rates of 17 pa-tients in 3 ,6 and 9 months after CI were 9%±3%,8%±4% and 9%±2%,respectively.The single consonant recognition rates were not significantly improved after than before CI (8%±2%).Conclusion ① For patients with bi-lateral cochlear neural canal stenosis,neither ECAP nor EABR waves were produced during or after CI.The language com-munication of patients is limited as a result of their poor subjective thresholds in sound field and speech recognition rates.

Objective To introduce the development of facial recess of 210 cases who recieved cochlear implantation and experienced the opening of the facial recess under the direction of high resolation computed tomography(HRCT).Methods The facial recess was assessed and measured using the HRCT before cochlear implantation in 210 patients who suffered from severe and profound sensorineural hearing loss.A statistic analysis was performed according to the age group,and the findings during the operation were compared with that before the surgery.Results The facial recess of 13 cases (6%) did not developed.The mean volume of the rest facial recess was 4.26 mm3 in 197 cases,while in 12.0 years group(group C) it was 3.09 mm3.The differences among three groups were statistically significant. The findings during the operation was agreed with the assessment results prior to the surgery.Conclusion 94% facial recesses developed in all 210 cases.Employment of HRCT scan prior to the surgery allows auurate determination of the location of facial recess to ensure successful surgery.

OBJECTIVE: To investigate the feasibility of the round window stimulation electrical evoked auditory brainstem response (EABR) test, and optimize the parameters of recording and stimulation electrodes positions. METHOD: Ten healthy Hartley guinea pigs (20 ears) were used for the EABR test. The positive stimulation electrodes were placed into the round window niche, the animals were divided into three group according to the negative electrodes position, group A: the electric field was parallel with the projection of cochlear modiolus on the tympanic membrane, group B: the electric field was perpendicular to modiolus projection toward to the mastoid, group C: the electric field was perpendicular to modiolus projection toward to the zygomatic process. A series of optimized recording and stimulation parameters were uesed to reduce the electrical artifact. RESULT: All the 20 ears were normal in the ABR testing, and EABR waves were stable and well-differentiated in the EABR tests out of cochlea. But EABR waves of group A were more stable and differentiated than those of group B and C. In group A, the threshold of EABR was (0.54 ± 0.11) mA, and latency of wave III was (1.71 ± 0.05) ms when the stimulus intensity was 0.8 mA. In group B, the threshold of EABR was (0.62 ± 0.12) mA, and latency of wave III was (1.77 ± 0.03) ms. In group C, the threshold of EABR was (0.70 ± 0.14) mA, and latency of wave III was (1.86 ± 0.04)ms. The threshold of EABR and latency of wave III were significantly different among the three groups by statistic analysis. CONCLUSION EABR waves were stable and well-differentiated in the EABR tests out of cochlea. The EABR waves were recorded more stably and differentiated when the stimulating electrode and recording electrode were paralleled with the projection of modiolus on the tympanic membrane.
Animals ; Cochlea ; physiology ; Electric Stimulation ; Electrodes ; Evoked Potentials, Auditory, Brain Stem ; Guinea Pigs ; Round Window, Ear ; Tympanic Membrane

Objective To summarize 5 otospongiosis cases with profound sensory hearing loss who received cochlear implante(CI) in routine way.To analyze their characteristics in audiology and temporal CT,and the effects after CI.Methods 5 cases of profound sensorineural hearing loss with otospongiosis received pure tone test,otoacoustic emission,auditory brainstem evoked potential and temporal CT before operation.One of the patients received binaural CIs.Mapping was done one month after operation.Follow-up tests were provided 6 months after operation to assess the effects.Results 5 cases showed clinical characteristics of gradual binaural hearing reduction,PTA greater than 90 dB HL,mixed or sensorineural deafness,normal tympanic membranes,reduced peaks in acoustic impedance,and typical CT findings.5 patients(6 ears) were implanted in routine manner.It was difficult to open the cochlea scala tympani.The scala tympani was filled with loose bony tissues.It was about 7～9 mm between the round window and the normal scala tympani.All patients showed the standard wave from in nerves reaction remote monitoring.The patients were followed up from 8 months to 3.1years.The average PTA was 20～37dB HL.The speech discrimination score was 95%～99% for open Chinese audiometry.Conclusion CI was an effective way to help patients with profound sensory hearing loss and otospongiosis.

Objective To explore the threshold and latency of patients receiving cochlear implantation using electrically evoked auditory brainstem responses (EABR), and to evaluate the significance of EABR applied to those patients.Methods The EABR and ECAP were recorded in 14 subjects who were operated for Nucleus24 cochlear implant.They were assigned to Group A and Group B according to the results of ECAP. The threshholds of EABR, the wave latency of III and V and inter-wave latency of III-V of EABR were compared and analyzed between Group A and Group B.Results The threshholds of EABR were higher in Group B than in Group A on electrode No 22 when the pulse width was 25,50,75,100,125 ?s,respectively. There were significant differences between Group A and Group B(P0.05).Conclusion The threshholds of EABR were lower in patients whose ECAP findings were positive. The latencies of III and V,and inter-wave latency of III–V of EABR had no significant difference according to the positive findings of ECAP.

Objective To find out the changes of voice in different noisy background by computer acoustic analysis.Methods 25 young people with normal hearing and normal vocal cords were selected.Sustained /a/ and /i/ were recorded in three different background:quiet, white band noise and speech noise. The software of Multi Speech and Doctor Speech were used. Testing parameters included: Fo, mean amplitudes, standard deviations of amplitudes,F 1, F 2.Results Fundamental frequencies of noisy groups were significantly higher in male-/a/, female-/a/ and female-/i/.F 1 of noisy groups were significantly higher in male-/a/, male-/i/ and female-/i/.Conclusion Fo and F 1 of normal people can be changed by noise of backgroud.