Effect of hearing aids on hearing

We examined 114 patients aged 10 to 91 years with different kinds of hearing aids fitted in one ear only, the unaided ear acting as a control. They were re-examined several times during a period of follow-up from 1 to 9 years comparing the relative change in hearing due to hearing aid usage with various degrees of amplification of the aid. We compared the degree of hearing loss in the aided and unaided ear looking for evidence of a possible change in hearing related to the frequency of hearing aid usage in hours per day and in years, the maximum power output (MPO) and the gain of the aid. According to our findings there is no change in hearing between the aided and the unaided ear at the alpha = 0.05 probability level at least for 8 years. There is no effect of the long-term amplification of the hearing aid on deterioration of hearing comparing the aided ear and the unaided ear, but with high MPO of the aid, the patient should be followed up more frequently than with low MPO amplification.     

极重度聋及其听力康复技术

根据世界卫生组织(WHO-1997)的听力障碍分级标准,极重度聋是指好耳侧500Hz、1000Hz、2000Hz、4000Hz处的纯音听阈均值大于80dB HL。较我国1987年第一次残疾人口调查时采用的听力残疾分级标准有较大改变,一是增加了测试频率4000Hz,二是听阈标准由90dB HL降低至80dB HL。2006年,我国第二次全国残疾人口抽样调查采用了新的听力残疾分级标准,既考虑到我国原先使用的标准又做到了与国际接轨。我国新标准将世界卫生组织标准中的极重度聋细分为听力残疾一级和听力残疾二级,听阈在81～90dB HL为二级,在90dB HL以上为一级。严重的听力障碍…     

Implantable hearing aids for moderate-to-severe hearing loss

Common modalities of aural rehabilitation include external hearing aids, cochlear implantation, and bone anchored hearing aids. In recent years, there has been research, development, and application of implantable and semi-implantable hearing aids. These devices act by vibration of the ossicular chain by piezoelectric or electromagnetic energy. Although only recently approved by the U.S. Food and Drug Administration, implantable hearing aids are evolving as a plausable option for patients with sensorineural or conductive hearing loss. Here, we review all current devices and surgical techniques for implantation.     

Rehabilitation of patients with hearing disorders using hearing aids and tactical hearing measures

After a brief summary of the problems of rehabilitation of hearing-impaired subjects, the optimal conditions for rehabilitation with hearing aids are presented: a) The right timing is crucial. b) Optimal provision of hearing aids must be carried out in close co-operation between the patient, the hearing aid technician and the otolaryngologist. c) Easy handling of the hearing aid and the use of attachments must be guaranteed. d) The hearing-impaired person must be fully informed as to the extent and type of hearing loss. He/she must accept the affliction and know about the possibilities of rehabilitation. The patient's motivation is a pre-requisite for all further steps. e) The patients must learn tactical measures to make optimal use of their hearing ability in relation to their environment. Hearing tactics consist of hearing training and a change in the attitude of the hearing-impaired patients themselves and their attitude towards their surroundings.     

听力障碍新生儿随访中听力恢复正常的原因分析

目的：分析新生儿普遍听力筛查中3个月内诊断为听力障碍婴儿其听力恢复正常的原因。方法：2001年11月～2005年6月在上海市出生并接受新生儿普遍听力筛查未通过者,转至上海市儿童听力障碍诊治中心接受听力学评估,均在出生3个月内诊断为听力障碍,并进行听力学跟踪随访至少6个月,对听力恢复正常者进行分析。结果：出生3个月内诊断为听力障碍者681例,随访6～24个月听力恢复正常者94例（115耳）,占13．8％。听力恢复正常者中发现有鼓室积液56例（64耳）,占59．6％;未发现有明确器质性原因者38例（51耳）,占40．4％。听力恢复正常115耳中听力障碍轻度105耳,占91．3％;中度8耳,占7．0％;中重度2耳,占1．7％;重度和极重度无恢复正常者。结论：出生3个月内诊断有听力障碍的患儿,随年龄增长其听力恢复正常的可能性以轻、中度聋为大。恢复原因主要是分泌性中耳炎自愈和听中枢生理性发育逐渐成熟。     

Frequency compression hearing aid for severe-to-profound hearing impairments

(1) Objective: Objective of this study is to know how a frequency compression hearing aid with new concepts is beneficial for severe-to-profound hearing impairments. (2) Methods: Clinical trials of this hearing aid were conducted for 11 severe-to-profound hearing impaired listeners. These 11 wore the frequency compression hearing aid in their daily life and reported subjectively on its performance. Speech recognition tests with five listeners and audio-visual short sentence recognition tests with three listeners were also conducted. This hearing aid can separately adjust the fundamental frequency from the spectral envelope of input speech and can adjust frequency response by use of a post-processing digital filter. (3) Results: Five listeners out of these 11 came to prefer this hearing aid in their daily life and are still wearing it. The results of the speech recognition tests show that the speech recognition scores were not improved for all listeners and the results of the audio-visual short sentence recognition tests do that the audio-visual recognition scores were improved for two listeners. (4) Conclusion: There were some severe-to-profound hearing impaired listeners who preferred the frequency compression hearing aid finally. It is also suggested that the benefits of this hearing aid may be evaluated correctly using not only speech but also visual materials.     

The influence of hearing loss on directional hearing

Fifty patients with cochlear hearing loss were tested with phase audiometry. Thirty-three of the patients had unilateral hearing loss at 500 Hz and 17 bilateral, symmetrical hearing loss at 500 Hz. Those patients who had slight hearing loss (less than 40 dB HL) had as a rule normal directional hearing. Those who had hearing loss exceeding 40 dB HL at 500 Hz usually had abnormal directional hearing. The sound lateralization ability was independent of whether the hearing loss was unilateral or bilateral.     

Evaluation of hearing improvement due to hearing aids

A method to assess the hearing improvement due to hearing aids is described. This method has been used routinely at a local hospital for 2 years on 200 patients. This method is based on the assessment of the speech reception threshold for sentences ("Marburger Satztest") in silence and in various noise levels (speech simulating noise). The following were used for the assessment of the hearing aid: the improvement of the speech reception threshold in silence with or without a hearing aid, the maximum tolerable noise level (i.e. the noise level at which everyday speech becomes subliminal for patients with hearing aids) and the noise level at which the speech reception threshold with the hearing aid is worse than without.     

Wireless and acoustic hearing with bone-anchored hearing devices

Objective: The efficacy of wireless connectivity in bone-anchored hearing was studied by comparing the wireless and acoustic performance of the Ponto Plus sound processor from Oticon Medical relative to the acoustic performance of its predecessor, the Ponto Pro. Study sample: Nineteen subjects with more than two years' experience with a bone-anchored hearing device were included. Thirteen subjects were fitted unilaterally and six bilaterally. Design: Subjects served as their own control. First, subjects were tested with the Ponto Pro processor. After a four-week acclimatization period performance the Ponto Plus processor was measured. In the laboratory wireless and acoustic input levels were made equal. In daily life equal settings of wireless and acoustic input were used when watching TV, however when using the telephone the acoustic input was reduced by 9?dB relative to the wireless input. Results: Speech scores for microphone with Ponto Pro and for both input modes of the Ponto Plus processor were essentially equal when equal input levels of wireless and microphone inputs were used. Only the TV-condition showed a statistically significant (p?<5%) lower speech reception threshold for wireless relative to microphone input. In real life, evaluation of speech quality, speech intelligibility in quiet and noise, and annoyance by ambient noise, when using landline phone, mobile telephone, and watching TV showed a clear preference (p?<1%) for the Ponto Plus system with streamer over the microphone input. Due to the small number of respondents with landline phone (N?=?7) the result for noise annoyance was only significant at the 5% level. Conclusion: Equal input levels for acoustic and wireless inputs results in equal speech scores, showing a (near) equivalence for acoustic and wireless sound transmission with Ponto Pro and Ponto Plus. The default 9-dB difference between microphone and wireless input when using the telephone results in a substantial wireless benefit when using the telephone. The preference of wirelessly transmitted audio when watching TV can be attributed to the relatively poor sound quality of backward facing loudspeakers in flat screen TVs. The ratio of wireless and acoustic input can be easily set to the user’s preference with the streamer’s volume control.     

Spatial hearing of normally hearing and cochlear implanted children

Objective

Spatial hearing uses both monaural and binaural mechanisms that require sensitive hearing for normal function. Deaf children using either bilateral (BCI) or unilateral (UCI) cochlear implants would thus be expected to have poorer spatial hearing than normally hearing (NH) children. However, the relationship between spatial hearing in these various listener groups has not previously been extensively tested under ecologically valid conditions using a homogeneous group of children who are UCI users. We predicted that NH listeners would outperform BCI listeners who would, in turn, outperform UCI listeners.

Methods

We tested two methods of spatial hearing to provide norms for NH and UCI using children and preliminary data for BCI users. NH children (n = 40) were age matched (6-15 years) to UCI (n = 12) and BCI (n = 6) listeners. Testing used a horizontal ring of loudspeakers within a booth in a hospital outpatient clinic. In a ‘lateral release’ task, single nouns were presented frontally, and masking noises were presented frontally, or 90° left or right. In a ‘localization’ task, allowing head movements, nouns were presented from loudspeakers separated by 30°, 60° or 120° about the midline.

Results

Normally hearing children improved with age in speech detection in noise, but not in quiet or in lateral release. Implant users performed more poorly on all tasks. For frontal signals and noise, UCI and BCI listeners did not differ. For lateral noise, BCI listeners performed better on both sides (within ∼2 dB of NH), whereas UCI listeners benefited only when the noise was opposite the unimplanted ear. Both the BCI and, surprisingly, the UCI listeners performed better than chance at all loudspeaker separations on the ecologically valid, localization task. However, the BCI listeners performed about twice as well and, in two cases, approached the performance of NH children.

Conclusion

Children using either UCI or BCI have useful spatial hearing. BCI listeners gain benefits on both sides, and localize better, but not as well as NH listeners.     

Natural history of contralateral residual hearing in binaural-bimodal hearing

Conclusions. The range of evaluation tools used in deciding which ear to implant and which to designate for a hearing aid (HA) should be expanded to include additional aspects to those tested by audiometry and basic speech perception. Residual hearing in non-implanted ears remains stable for at least 3 years after unilateral cochlear implantation, but regular refitting and monitoring of the HA function combined with cochlear implant (CI) mapping are mandatory for maximizing benefit from binaural-bimodal hearing. Objectives. To examine whether the clinical decision-making tools currently used to assess hearing are reliable guides when choosing the preferred ear for CI, and to determine the rate of residual hearing deterioration in the non-implanted ear over 36 months post-CI as a guide to recommending subsequent continued use of a contralateral HA as opposed to CI. Patients and methods. This was a retrospective evaluation of patients’ charts. The pre-CI choice of the ear for implantation in a group of 37 binaural-bimodal users was re-evaluated. In a second group of 22 patients, residual hearing deterioration was followed for 36 months post-implantation. Results. In the group of 37 patients, subjective identification of the worse-hearing ear was in agreement with audiometric results in 28 cases, but disagreed with the unaided audiometric results in the other 9. Mean threshold values for the group of 22 patients remained stable over 36 months post-CI, except for the aided threshold at 4.0kHz, which deteriorated by 10.9dB (p=0.003).     

Impedance audiometric characteristics of hearing after hearing improving operations

A complete audiological examination including impedance audiometry conducted in patients with otitis media purulenta chronica (n = 22), adhesive otitis media (n = 20), otosclerosis (n = 14) and family hypoacusis (n = 8) has detected signs of neurosensory hypoacusis (NH). Follow-up results indicated NH progression. Thus, affection of the middle ear manifests with symptoms of conductive and neurosensory hypoacusis. NH was treated surgically with temporary effect.     

Digital hearing aids and future directions for hearing aids

In recent years many technical evolutions have been applied in hearing aids. In this paper differences between analog, programmable and fully digital hearing aids, the basic and supplementary functions of a hearing aid, and some important issues and future directions for digital hearing aids will be mentioned.     

Dexamethasone base conserves hearing from electrode trauma-induced hearing loss

Objective/Hypothesis: Local treatment of the cochlea after electrode insertion trauma with dexamethasone base conserves hearing against trauma‐induced loss. Study Design: Laboratory animal study. Methods: A guinea pig model of electron insertion trauma (EIT)‐induced hearing loss (HL) used 44 guinea pigs sub‐divided into four groups: 1) unoperated, controls (Controls, n = 44); 2) EIT, untreated (EIT, n = 15); 3) EIT plus artificial perilymph (EIT + AP, n = 15); and 4) EIT plus dexamethasone base (EIT + DXMb, n = 14). Cochleae that received EIT were randomly selected with contralateral, unoperated cochleae as internal controls. Auditory brainstem responses (ABRs) in response to 0.5 to 16 kHz pure tones were obtained before surgery, immediately after surgery (0 day), and on post‐EIT days 3, 7, 14, and 30. Hair cell counts were obtained from stained organ of Corti specimens from all four groups (n = 3/group). Data were analyzed using analysis of variance and a Tukey‐Kramer honestly significant difference post hoc test with significance alpha set at <0.05 (hearing) and <0.001 (hair cells). Results: There were significant differences (<0.05) between the ABR thresholds of unoperated (control) and contralateral operated (experimental) ears of EIT and of EIT + AP groups for all tested frequencies. There was no statistical difference (>0.05) in ABR thresholds in the EIT + DXMb versus control groups for 0.5 to 4 kHz tones. DXMb treatment protected hair cells from EIT‐induced damage and loss while AP treatment did not. Conclusion: The absence of significant differences in hearing thresholds between the EIT + DXMb group and control ears in response to 0.5 to 4 kHz tones demonstrates that DXMb is as effective as the aqueous form of dexamethasone in conserving hearing against EIT‐induced loss.