Demin Han

Lexical tone perception with HiResolution and HiResolution 120 sound-processing strategies in pediatric Mandarin-speaking cochlear implant users.

Objectives: Lexical tone recognition tends to be poor in cochlear implant users. The HiResolution (HiRes) sound-processing strategy is designed to better preserve temporal fine structure, or the detailed envelope information, of an acoustic signal. The newer HiRes 120 strategy builds on HiRes by increasing the amount of potential spectral information delivered to the implant user. The purpose of this study was to examine lexical tone recognition in native Mandarin Chinese-speaking children with cochlear implants using the HiRes and HiRes 120 sound-processing strategies. Tone recognition performance was tested with HiRes at baseline and then after up to 6 mo of HiRes 120 experience in the same subjects. Design: Twenty prelingually deafened, native Mandarin-speaking children, with ages ranging from 3.5 to 16.5 yr, participated. All children completed a computerized tone contrast test on three occasions: (1) using HiRes immediately before conversion to HiRes 120 (baseline), (2) 1 mo after conversion, and (3) 3 mo after conversion. Twelve of the 20 children also were tested 6 mo after conversion. In addition, the parents of 18 children completed a questionnaire at the 3-mo follow-up visit regarding the preference of sound-processing strategies and the childrens experience related to various aspects of auditory perception and speech production using HiRes 120. Results: As a group, no statistically significant differences were seen between the tone recognition scores using HiRes and HiRes 120. Individual scores showed great variability. Tone recognition performance ranged from chance (50% correct) to nearly perfect. Using the conventional HiRes strategy, 6 of the 20 children achieved high-level tone recognition performance (i.e., ≥90% correct), whereas 7 performed at a level not significantly different from chance (50–60% correct). At the final test, either 3 or 6 mo after conversion, all children achieved tone recognition performance with HiRes 120 that was equal to or better than that with HiRes, although some childrens tone recognition performance was worse initially at the 1 or 3 mo follow-up intervals than at baseline. Eight of the 20 children showed statistically significant improvement in tone recognition performance with HiRes 120 on at least one of the follow-up tests. Age at implantation was correlated with tone recognition performance at all four test intervals. Parents of most of the children indicated that the children preferred HiRes 120 more than HiRes. Conclusions: As a group, HiRes 120 did not provide significantly improved lexical tone recognition compared to HiRes, at least throughout the length of the study (up to 6 mo). There were large individual differences in lexical tone recognition among the prelingually deafened, native Mandarin-speaking children with cochlear implants using either HiRes or HiRes 120. Six of the 20 children performed at or near ceiling in the baseline HiRes condition. Of the remainder, approximately half showed significantly better tone recognition when subsequently tested with HiRes 120, although the extent to which this improvement may be attributable to factors other than the change in processing strategy (e.g., general development) is unknown. The children who benefited most from HiRes 120 tended to be those who were implanted at younger ages.

Tone Production in Mandarin-speaking Children with Cochlear Implants: A Preliminary Study

Objective More than a quarter of the worlds population speak tone languages, such as Mandarin Chinese. In those languages, the pitch or tone pattern of a monosyllabic word conveys lexical meaning. The purpose of this study was to investigate tone production in Mandarin-speaking children with cochlear implants (CIs). Material and Methods Speech samples were recorded from seven normal-hearing and four CI children aged 4–9 years. All subjects were native Mandarin speakers. The speech samples were used for acoustic analysis of the tone patterns, i.e. the fundamental frequency contours. In addition, a tone intelligibility test was carried out in which four normal-hearing native Mandarin-speaking adults listened to the speech materials and judged the intelligibility of the childrens tone production. Results The tone production for the seven normal-hearing children was considered to be perfect in the intelligibility test. Acoustic analysis of the speech materials of the normal-hearing children produced the four typical tone patterns of Mandarin Chinese: (i) high and flat; (ii) rising; (iii) low and dipping; and (iv) falling. The tone patterns produced by the children with CIs tended to be flat, with some other patterns being irregular. The results of the tone intelligibility tests also showed degraded intelligibility of tone patterns. Conclusion A potential speech development deficit was documented in prelingually deafened children with CIs whose native language is a tone language. The imperfect tone production of the implant children, which can be attributed to the paucity of pitch information delivered via the current CI stimulation, may have significant implications for communication using tone languages. Further research is warranted to determine factors that may affect tone development in children with CIs.

Tone perception and production in pediatric cochlear implants users

Abstract Conclusions: In prelingually deaf children with cochlear implants, tone perception and production performance are highly correlated. This result is consistent with the hypothesis that tone perception is the prerequisite for good tone production. Objectives: Previous research has shown remarkable deficits in tone perception and production in native tone language-speaking, prelingually deafened children with cochlear implants. The purpose of the present study was to investigate the relationship between tone perception and production in those children. Methods: Twenty-five prelingually deaf children with cochlear implants participated in the study. All subjects were Advanced Bionics CII/90K users with various lengths of implant use. To evaluate tone perception performance, subjects completed a computerized tone contrast test. For tone production performance, an artificial neural network was used to evaluate the accuracy of tones recorded from each of the 25 subjects. Results: Large individual differences in tone perception and production performance were observed in these subjects. Tone perception accuracy ranged from 50.0 to 96.9% correct (chance performance = 50% correct; mean = 71.0% correct). Tone production performance ranged from 19.4 to 97.2% correct (mean = 52.0% correct). A strong correlation was found between tone perception and production performance in this group of subjects (r = 0.805).

Vocal singing by prelingually-deafened children with cochlear implants

The coarse pitch information in cochlear implants might hinder the development of singing in prelingually-deafened pediatric users. In the present study, seven prelingually-deafened children with cochlear implants (5.4-12.3 years old) sang one song that was the most familiar to him or her. The control group consisted of 14 normal-hearing children (4.1-8.0 years old). The fundamental frequencies (F0) of each note in the recorded songs were extracted. The following five metrics were computed based on the reference music scores: (1) F0 contour direction of the adjacent notes, (2) F0 compression ratio of the entire song, (3) mean deviation of the normalized F0 across the notes, (4) mean deviation of the pitch intervals, and (5) standard deviation of the note duration differences. Children with cochlear implants showed significantly poorer performance in the pitch-based assessments than the normal-hearing children. No significant differences were seen between the two groups in the rhythm-based measure. Prelingually-deafened children with cochlear implants have significant deficits in singing due to their inability to manipulate pitch in the correct directions and to produce accurate pitch height. Future studies with a large sample size are warranted in order to account for the large variability in singing performance.

The effects of age at cochlear implantation and hearing aid trial on auditory performance of Chinese infants

Abstract Conclusion: Most of the infants demonstrated rapid improvement in the three different auditory skills within the first year after switch-on. Infants undergoing hearing aid trial and habilitation demonstrated a significant positive effect on the development of auditory skills in comparison with infants without trial and habilitation. Objective: This paper aims to evaluate the auditory performance of infants of different age at cochlear implantation, emphasize the importance of the hearing aid trial and habilitation before implant, and provide baseline data of auditory development. Methods: In all, 259 infants with prelingually profound hearing loss participated in this study. The Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) was used to assess auditory skills in infants at different intervals. Results: The mean scores for the auditory skills improved significantly over time. The mean scores of three skills for each group at each interval were significantly different. The mean scores of the auditory skills were significantly superior for infants undergoing hearing aid trial and habilitation in comparison with those of infants without hearing aid trial and habilitation.

Comparisons between Neural Response Imaging thresholds, electrically evoked auditory reflex thresholds and most comfortable loudness levels in CII Bionic Ear users with HiResolution™ sound processing strategies

Conclusions. The data collected in this study indicated that first Neural Response Imaging (NRI) thresholds had a better correlation with HiResolution™ most comfortable loudness (M) levels than tNRI thresholds. Electrically evoked auditory reflex thresholds (EARTs) had a higher correlation with HiResolution M levels than tNRI thresholds and a lower correlation than first NRI thresholds. NRI is a very useful method for programming the cochlear implants of young children who cannot demonstrate a reliable judgment of loudness. Objective. To investigate how HiResolution sound processing, designed to deliver high-rate stimuli, relates to EARTs and electrically evoked compound action potential measurements produced by low-rate stimuli. Material and methods. Nine profoundly hearing-impaired children and adults aged 6–29 years participated in the study. NRI responses were elicited using pulse trains consisting of biphasic pulses at a pulse width per phase of 32 µs delivered at a frequency of 30 Hz using SoundWave programming software. Stimuli were delivered to the odd electrodes (1, 3, 5, 7, 9, 11, 13 and 15) along the array. tNRI (NRI threshold) and first NRI thresholds were recorded for each stimulating electrode. “Speech bursts” stimuli used in EARTs recording were delivered to four electrodes at a time and stapedial reflexes were recorded from the impedance bridge. The M levels used were those used by each patient in their everyday HiResolution programs. Results. For 8 patients (53 stimulating electrodes) the correlation between tNRI threshold and M level was ru200a=u200a0.675 (pu200a=u200a0.000) and that between first NRI thresholds and M level was r=0.741 (pu200a=u200a0.000). On average the M-level value was 20 CU (Current Unit) lower than the first NRI threshold value and 12 CU higher than the tNRI threshold value. The M-level patterns across the electrode array overall were similar to the tNRI or first NRI threshold patterns. For 7 patients (112 stimulating electrodes) the correlation between EART and M levels was r=0.710 (pu200a=u200a0.000). On average the EART value was 14 CU higher than the M-level value.

Effects of lexical characteristics and demographic factors on mandarin chinese open-set word recognition in children with cochlear implants.

Objective: The purpose of this study was to examine the open-set word recognition performance of Mandarin Chinese–speaking children who had received a multichannel cochlear implant (CI) and examine the effects of lexical characteristics and demographic factors (i.e., age at implantation and duration of implant use) on Mandarin Chinese open-set word recognition in these children. Design: Participants were 230 prelingually deafened children with CIs. Age at implantation ranged from 0.9 to 16.0 years, with a mean of 3.9 years. The Standard-Chinese version of the Monosyllabic Lexical Neighborhood test and the Multisyllabic Lexical Neighborhood test were used to evaluate the open-set word identification abilities of the children. A two-way analysis of variance was performed to delineate the lexical effects on the open-set word identification, with word difficulty and syllable length as the two main factors. The effects of age at implantation and duration of implant use on open-set, word-recognition performance were examined using correlational/regressional models. Results: First, the average percent-correct scores for the disyllabic “easy” list, disyllabic “hard” list, monosyllabic “easy” list, and monosyllabic “hard” list were 65.0%, 51.3%, 58.9%, and 46.2%, respectively. For both the easy and hard lists, the percentage of words correctly identified was higher for disyllabic words than for monosyllabic words, Second, the CI group scored 26.3%, 31.3%, and 18.8 % points lower than their hearing-age–matched normal-hearing peers for 4, 5, and 6 years of hearing age, respectively. The corresponding gaps between the CI group and the chronological-age–matched normal-hearing group were 47.6, 49.6, and 42.4, respectively. The individual variations in performance were much greater in the CI group than in the normal-hearing group, Third, the children exhibited steady improvements in performance as the duration of implant use increased, especially 1 to 6 years postimplantation. Last, age at implantation had significant effects on postimplantation word-recognition performance. The benefit of early implantation was particularly evident in children 5 years old or younger. Conclusions: First, Mandarin Chinese–speaking pediatric CI users’ open-set word recognition was influenced by the lexical characteristics of the stimuli. The score was higher for easy words than for hard words and was higher for disyllabic words than for monosyllabic words, Second, Mandarin-Chinese–speaking pediatric CI users exhibited steady progress in open-set word recognition as the duration of implant use increased. However, the present study also demonstrated that, even after 6 years of CI use, there was a significant deficit in open-set, word-recognition performance in the CI children compared with their normal-hearing peers. Third, age at implantation had significant effects on open-set, word-recognition performance. Early implanted children exhibited better performance than children implanted later.

The value of preoperative CT scan of tympanic facial nerve canal in tympanomastoid surgery

Abstract Conclusions: The combined analysis of axial, coronal, and sagittal planes can increase the positive rate of diagnosis for dehiscence of the facial nerve canal. Objective: The aim of this study was to evaluate the diagnostic value of high resolution computed tomography (HRCT) scanning of the condition of the tympanic portion of the facial nerve canal in patients with chronic otitis media. Methods: A total of 76 ears of 72 inpatients with chronic suppurative otitis media and with cholesteatoma or granulation tissues in the attic were examined by routine HRCT. The condition (including dehiscence) of the tympanic portion of the facial nerve canal observed by CT on multi-planar images and surgical findings were recorded. Results: The condition of the tympanic portion of the facial nerve canal observed by CT could be confirmed by surgical findings in 67/76 ears, but was not confirmed in 9/76 ears. Axial-transverse images could clearly show the position and length of dehiscence on the lateral wall of the facial nerve, while coronal images were superior to axial-transverse images in showing the bony circumference of the facial nerve, and sagittal images could show the inferior wall of the facial nerve canal more clearly than images on the former planes.

Facial nerve course in congenital aural atresia – identified by preoperative CT scanning and surgical findings

Conclusions. The facial nerve courses shown by preoperative CT imaging coincide with the surgical findings in most congenital aural atresia cases. CT scanning is critical in evaluation of a patients candidacy for atresia surgery. Objectives. To evaluate the diagnostic value of preoperative CT scanning of the facial nerve course in congenital aural atresia. Subjects and methods. All inpatients (135 cases) with congenital aural atresia had routine preoperative CT examination. The facial nerve courses were observed in the operation and compared with the preoperative CT imaging. Results. CT imaging showed that the mastoid portions of the facial nerves in 57% of cases (77/135) were located at the level of the round window, and 17% (23/135) were located at the levels of the oval window and the cochlea. Differential overlapping of the oval window by the facial nerve could also be shown in most of the cases. In the majority of cases (75%, 61/81) the tympanic portions of the facial nerve on CT imaging could be confirmed by surgical findings. In severe overlapping of the oval window or cases with anterior displacement, stapedectomy or tympanoplasty, respectively, could not be performed as usual.

Integrated protocol of auricle reconstruction combined with hearing reconstruction

Abstract Conclusions: Auricle reconstruction combined with hearing reconstruction can help patients with microtia to obtain practical hearing improvement as well as cosmetic improvement. The integrated procedures can facilitate the incision design and obtain a natural-looking three-dimensional shape of the reconstruction auricle. Objectives: To discuss the advantages of an integrated protocol for auricle reconstruction combined with hearing reconstruction. Methods: We retrospectively analyzed the clinical information and follow-up results of 1300 cases (1460 ears) of congenital aural atresia with microtia who underwent auricle reconstruction combined with hearing reconstruction from January 1988 to December 2007 in Tongren Hospital. In the first stage, rib cartilage was harvested to sculpt the framework then implanted into the subcutaneous pockets in the desired position. In addition, hearing reconstruction was carried out by the antrum approach. In the second stage, the auricle framework was elevated to accomplish the auricle reconstruction. Results: In all, 1445 of 1460 ears were closed by primary healing. The other 15 ears were successfully reconstructed with revision surgeries without graft failure complications. The three-dimensional profiles were well defined in 1248 ears. Total satisfaction rate was 85.5%. During the long-term follow-up, no cartilage resorption was found and all auricles retained good cosmetic effects.