Neonatal screening for hearing disorders in infants at risk: incidence, risk factors, and follow-up.

OBJECTIVE: To determine the incidence and risk factors for hearing disorders in a selected group of neonates and the feasibility of selective hearing screening. SETTINGS: Multicenter prospective trial at five centers in Germany. METHODS: Enrollment criteria: in addition to previously defined risk factors by the Joint Committee on Infant Hearing (family history of hearing loss, in utero infections, craniofacial anomalies, birth weight <1500 g, critical hyperbilirubinemia, ototoxic medications, bacterial meningitis, postnatal asphyxia, mechanical ventilation >5 days, stigmata, or syndromes associated with hearing loss), the impact of maternal drug abuse, birth weight <10th percentile, persistent pulmonary hypertension, and intracranial hemorrhage more than or equal to grade III or periventricular leukomalacia on infant hearing were evaluated. The screening procedure was performed by automated auditory brainstem response (A-ABR; ALGO 1-plus; Natus Med Inc, San Carlos, CA). STATISTICS: univariate analyses of risk factors versus A-ABR results and a multivariate regression analysis were used; additionally, the total test time was recorded. RESULTS: Seven hundred seventy recordings from 777 infants enrolled consecutively constitute the basis of this analysis. Mean gestational age was 33.8 +/- 4.3 weeks, birth weight 2141 +/- 968 g; 431 infants being male and 339 female; 41 (5.3%) infants exhibited pathologic A-ABR results (16 bilateral and 25 unilateral). Meningitis or sepsis, craniofacial malformations, and familial hearing loss were independent significant risk factors. Median total test time was 25 minutes. Follow-up examinations in 31 infants revealed persistent hearing loss in 18 infants (13 infants sensorineural, 5 from mixed disorders), 7 requiring amplification. CONCLUSION: Hearing screening in high-risk neonates revealed a total of 5% of infants with pathologic A-ABR (bilateral 2%). Significant risk factors were familial hearing loss, bacterial infections, and craniofacial abnormalities. Other perinatal complications did not significantly influence screening results indicating improved perinatal handling in a neonatal population at risk for hearing disorders.

[Clinical and audiological findings in children with auditory neuropathy]. / Klinische und audiologische Befunde von Kindern mit auditorischer Neuropathie und ihre Versorgung mit einem Cochlea-Implantat.

BACKGROUND: Auditory neuropathy is a disorder characterised by preservation of outer hair cells function with normal otoacoustic emissions (OAEs), but with absent auditory brainstem responses (ABR). Perisynaptic synchronisation disorder is one of the possible pathogenesis underlying auditory neuropathy. In this paper we describe the clinical presentation and audiological findings in pediatric auditory neuropathy and its management. PATIENTS AND METHODS: 9 children with auditory neuropathy could be included in the study. An audiological evaluation was performed in all children including behavioural audiometry, measurement of the OAEs as well as electrocochleography (ECoG) and ABR recordings. Children who failed to get any benefit from conventional amplification received a cochlear implant. Prior to implantation the responses to electrical stimuli were examined with the promontory test and with the electrically evoked ABR. RESULTS: One child showed auditory neuropathy only on one side with normal hearing thresholds on the contralateral ear. Another child had normal hearing thresholds after the follow up period. Four children received a hearing aid. But variable hearing reactions were observed. Thus in three cases a CI is planned. In three children cochlea implantation was done. Following implantation a remarkable improvement in hearing/speech capabilities with the CI compared to conventional hearing aids were observed in all three cases. Beside, these three children developed open set speech discrimination and are using now oral language for communication. CONCLUSIONS: Auditory neuropathy is a disorder which presents with different clinical and audiological findings. Thus the management of this disorder must be an individual one. In light of our findings we support the use of cochlear implants as an option for children with auditory neuropathy in cases where conventional amplification does not work sufficiently.

[Congenital hearing loss. Molecular genetic diagnosis of connexin genes and genetic counselling]. / Kongenitale Schwerhörigkeit. Molekulargenetische Diagnostik der Connexin-Gene und genetische Beratung.

BACKGROUND: About 50% of congenital non-syndromic hearing impairment is caused by genetic factors. Research on the genetics of deafness has revealed a vast number of relevant genes. Mutations in the GJB2 gene have been shown to be the most common in several populations. METHODS: Mutation analysis of the genes for connexin 26, 30 and 31 (GJB2, GJB6 and GJB3) was performed in 67 patients with profound hearing loss. RESULTS: Of the participants, 9% had two pathogenic mutations in the GJB2 gene. Pedigree information indicates that in these families further offspring have a 25% to a 100% chance of having hearing impairment. CONCLUSIONS: Patients with non-syndromic hearing impairment should be offered molecular diagnostics of the GJB2 gene. Genetic counseling is mandatory for mutation carriers in order to advise them on the individual consequences of the gene test results.

[Tympanic effusion]. / Der Paukenerguss.

Since epidemiologic studies have shown, that the majority of middle ear effusions disappear spontaneously and sequelae a less frequent than expected, a more conservative treatment strategy is advisable. In this review pathogenetic factors are discussed and a treatment policy is recommended as it appears logic to the authors. It is stressed that exact audiologic data are difficult to obtain in children. If an effusion persists at least for 3 months, adenoidectomy, paracentesis and aspiration of the middle ear fluid has to be considered. The insertion of middle ear ventilation tubes is not the first step in our treatment. Special strategies for treatment have to be applied in some groups such as children with Francheschetti or Down Syndrome and children with cleft palates as well as in children with retardation in speech development.

[Indications and surgical treatment of large middle ear abnormality]. / Indikation und chirurgische Behandlung der grossen Mittelohrmissbildung.

Children with atresia of the external auditory canal should undergo hearing assessment and fitting of a bone conduction hearing aid as early as possible to allow speech to develop normally. Surgery is done between 5 and 6 years of age, guided by high-resolution computed tomography, which provides a more precise diagnosis based on the abnormalities seen. The temporomandibular joint lies more posteriorly than normal due to aplasia or hypoplasia of the tympanic bone, so that the middle ear must be approached through the mastoid, resulting in a less favourable coupling to the middle ear structures. In unfavourable cases bone anchored hearing aids, creation of a meatus for fitting a hearing aid or a bone conduction hearing aid must be considered.

[Ototoxicity of cisplatin in children]. / Cisplatinototoxizität im Kindesalter.

BACKGROUND: The ototoxicity of cisplatin has long been well known for its damage to hair cells. However, the results of published studies vary widely with respect to the intensity and frequency of auditory damage. METHODS: We analyzed the data of 13 young children that have been treated with cisplatin for varying tumor diseases in established combination chemotherapy. The study focused on these major questions: How high is the rate of cisplatin-related incidents of hearing loss in relation to age, sex, nature of tumor, and total dosage of the administered cisplatin? How much does the supplementary application of further ototoxic medications affect the ototoxicity itself? RESULTS: Eight of 13 children examined showed regular hearing capacities in conformity with their age-group, 3 showed a bilateral, and one child showed an one-sided loss of auditory capacity. Deterioration of preexisting auditory damage was observed in one child. No relation to age, sex, nature of tumor, or dosage of administered cisplatin was established. Bilateral hearing loss occurred in three of these children, which indicates that possible synergy of aminoglycoside antibiotics and cisplatin should be investigated with respect to ototoxicity. CONCLUSION: The results indicate that cisplatin, especially in combination with other ototoxic drugs, can lead to severe hearing loss in young children. Since factors other than the possible synergy discusses above favorable to the development of auditory damage cannot be specified, every child under cisplatin therapy should undergo auditory checkups at brief intervals.

[Hearing disorders in children with Down's syndrome]. / Hörstörungen beim Down-Syndrom.

Among 4947 children in an outpatients unit for hearing disorders 102 children with Down's syndrome were seen and checked for hearing disorders. 57 had hearing deficiencies, 50 (88 %) conductive hearing loss, 4 (7 %) combined and 3 (5 %) a sensory neural hearing loss. Compared to other publications the number of very young children was very high. 32 patients under two years of age had a hearing disorder. The results underline the necessity of early diagnosis and follow up also in children with normal reactions during the first presentation. Early diagnosis enables early treatment, conservative, surgical or fitting with hearing aids, especially important in the rehabilitation of these children. Hearing aids may be given temporarily imploring communication during the development of the child.

An autoradiographic study of bone grafts in small animals.

Bone remodelling was studied in allografts and isografts by means of autoradiography. Collagen and proteoglycans of the organic bone matrix were labelled with H-3 amino acids and S-35 sodium sulphate. The principles of primary bone formation are followed in graft remodelling as well. Matrix breakdown and reformation are carried out by mononuclear cells. Components of the original matrix can be seen in osteoclasts, perivascular cells, osteoblasts, young osteocytes, and in new bone. The label allows tracing of these components and proves their reuse.

[Test set for the evaluation of hearing and speech development after cochlear implantation in children]. / Evaluationsset zur Hör-/Sprachentwicklung nach Cochlea-Implantation bei Kindern.

BACKGROUND: Since autumn 1998 the multicenter interdisciplinary study group "Test Materials for CI Children" has been compiling a uniform examination tool for evaluation of speech and hearing development after cochlear implantation in childhood. METHODS USED: After studying the relevant literature, suitable materials were checked for practical applicability, modified and provided with criteria for execution and break-off. For data acquisition, observation forms for preparation of a PC-version were developed. RESULTS: The evaluation set contains forms for master data with supplements relating to postoperative processes. The hearing tests check supra-threshold hearing with loudness scaling for children, speech comprehension in silence (Mainz and Göttingen Test for Speech Comprehension in Childhood) and phonemic differentiation (Oldenburg Rhyme Test for Children), the central auditory processes of detection, discrimination, identification and recognition (modification of the "Frankfurt Functional Hearing Test for Children") and audiovisual speech perception (Open Paragraph Tracking, Kiel Speech Track Program). The materials for speech and language development comprise phonetics-phonology, lexicon and semantics (LOGO Pronunciation Test), syntax and morphology (analysis of spontaneous speech), language comprehension (Reynell Scales), communication and pragmatics (observation forms). The MAIS and MUSS modified questionnaires are integrated. CONCLUSIONS: The evaluation set serves quality assurance and permits factor analysis as well as controls for regularity through the multicenter comparison of long-term developmental trends after cochlear implantation.

Comparison of the TEMPO+ ear-level speech processor and the cis pro+ body-worn processor in adult MED-EL cochlear implant users.

A study was conducted to compare the new MED-EL TEMPO+ ear-level speech processor with the CIS PRO+ body-worn processor in the COMBI 40/COMBI 40+ implant system. Speech tests were performed in 46 experienced subjects in two test sessions approximately 4 weeks apart. Subjects were switched over from the CIS PRO+ to the TEMPO+ in the first session and used only the TEMPO+ in the time between the two sessions. Speech tests included monosyllabic word tests and sentence tests via the telephone. An adaptive noise method was used to adjust each subject's scores to approximately 50%. Additionally, subjects had to complete a questionnaire based on their 4 weeks of experience with the TEMPO+. The speech test results showed a statistically significant improvement in the monosyllabic word scores with the TEMPO+. In addition, in the second session, subjects showed a significant improvement when using the telephone with the TEMPO+, indicating some learning in this task. In the questionnaire, the vast majority of subjects found that the TEMPO+ allows equal or better speech understanding and rated the sound quality of the TEMPO+ higher. All these objective and subjective results indicate the superiority of the TEMPO+ and are mainly attributed to a new coding strategy called CIS+ and its implementation in the TEMPO+. In other words, based on the results of this study, it appears that after switching over from the CIS PRO+ to the TEMPO+, subjects are able to maintain or even improve their own speech understanding capability.