C.-M. Schmidt

Left-right asymmetry in hearing loss following cisplatin therapy in children--the left ear is slightly but significantly more affected.

Objectives: Bilateral symmetric high frequency hearing loss is regarded as one of the main characteristics of cisplatin-induced ototoxicity. Hair-cell damage because of cisplatin is discussed as the leading cause of hearing loss. Our observations in long-term audiological follow-up of children treated with cisplatin did not always show the anticipated symmetry of hearing loss. Design: Pure-tone audiograms of 55 (34 m, 21 f) children receiving chemotherapy with cisplatin at Muenster university hospital were analyzed. We compared pure tone hearing thresholds, transient evoked otoacoustic emissions levels and distortion product otoacoustic emissions levels before and after chemotherapy with cisplatin. Results: After therapy, the 55 children showed slightly higher average hearing levels in the range 2000 to 8000 Hz in the left ear. The side difference was significant at 4000, 6000, and 8000 Hz. In girls, the effect was less pronounced than in boys. Conclusions: This result, on the one hand, indicates that the auditory system is already responding asymetrically at the cochlear level, on the other hand it underscores the need for further research into the pathophysiology of platinum ototoxicity. There are parallels with stronger effects to the left ear in oiseinduced hearing loss as described in literature. Special attention should be given to possible supracochlear pathways of damage. Clinicians should consider that cisplatin associated hearing loss is not necessarily symmetric.

Spontaneous Otoacoustic Emission Enhancement in Children with Reduced Speech-in-Noise Intelligibility

Reduced speech-in-noise intelligibility is one of the main difficulties experienced by children with auditory processing disorder (APD). Previous studies have established a relationship between the function of the medial olivocochlear system (MOCS) and reduced inhibition of otoacoustic emissions (OAE) in children with APD. This study measured spontaneous OAE (SOAE) in 27 children with reduced speech-in-noise intelligibility, and those of a control group matched by gender and age. A significantly higher prevalence of SOAE was found: 85% of the study group presented SOAE, 44% in the control group. An abnormally functioning MOCS with reduced inhibition could lead to an increase in SOAE. Identifying a higher prevalence and number of SOAE may be a helpful objective mean to include in an APD diagnosis test battery.

Feasibility of 1000 Hz tympanometry in infants: Tympanometric trace classification and choice of probe tone in relation to age

OBJECTIVES Universal newborn hearing screening (UNHS) has significantly reduced the age of children undergoing audiological examinations. Middle ear function is usually evaluated with tympanometry using a probe tone of 226 Hz, although higher frequencies are recommended in infants. The aim of this study was to compare the feasibility of 226 and 1000 Hz tympanometry for different trace classification systems in relation to age, risk factors for hearing loss and ear canal volume. METHODS Data from 577 infants (915 ears) <1 year were analyzed. Tympanograms were classified according to the classification systems of Jerger, Marchant et al. and Kei et al. and correlated with ear microscopy as the gold standard. Test quality parameters of tympanometry with probe tones of 226 and 1000 Hz were compared in four different age groups. RESULTS The trace classification following Kei et al. presented the best correlation to ear microscopy and reduced the number of unclassified tympanograms. The use of probe tones of 226 Hz in infants below the age of nine months showed a poor level of sensitivity. CONCLUSIONS We recommend the use of a 1000 Hz probe tone in infants at least up to the age of nine months. In this age group, 226 Hz tympanometry is inappropriate. In children with craniofacial abnormalities and smaller ear canal volumes, 1000 Hz tympanometry could be taken into consideration, even for older children. High-frequency tympanograms should be evaluated according to the classification system of Kei et al., which differentiates between peaked (normal) and flat (abnormal) curves.

Progressive hearing loss after completion of cisplatin chemotherapy is common and more pronounced in children without spontaneous otoacoustic emissions before chemotherapy

OBJECTIVE High frequency hearing loss following cisplatin chemotherapy is frequent in children and often necessitates the fitting of hearing aids. During therapy, hearing is usually monitored. Post-therapeutic follow-up does not routinely include monitoring of hearing, although there are indications that hearing thresholds can decline after therapy. METHODS Pure-tone audiograms taken from 27 children (17 males, 10 females) treated with cisplatin at Muenster university hospital (mean age 9.84 years, standard deviation 3.67 years) including an audiological follow-up at least 6 months after therapy, were analyzed retrospectively. RESULTS In follow-up tests after completion of therapy, 24.1% of all ears showed an increase in mean high frequency hearing thresholds (4-8 kHz). Post-therapeutic hearing deterioration was significant at 4 kHz and significantly more pronounced in children without measurable spontaneous otoacoustic emissions (SOAE) before therapy. Post-therapeutic hearing deterioration did not occur in ears with normal pure tone thresholds (≤ 10dB at all frequencies) after cisplatin therapy. No correlation was found between post-therapeutic hearing deterioration and cranial irradiation. CONCLUSIONS Cisplatin chemotherapy follow-up should include audiological monitoring in all children with elevated pure tone thresholds after therapy. Routine SOAE measurements taken as part of baseline audiometry before the start of chemotherapy can be taken into consideration.

Ein neuer Genort für eine autosomal dominante, nichtsyndromale Hörstörung (DFNA57) kartiert auf Chromosom 19p13.2 und überlappt mit DFNB15

BACKGROUND Non-syndromic hearing loss is the most genetically heterogeneous trait known in humans. To date, 54 loci for autosomal dominant non-syndromic sensorineural hearing loss (NSSHL) have been identified by linkage analysis. METHODS In this study a German pedigree has been identified segregating a progressive bilateral loss of lower and middle frequencies. RESULTS A genome-wide screening and linkage analysis revealed the existence of a new NSSHL locus (DFNA57). The phenotype was mapped to a 10 degrees Mbp interval on chromosome 19p13.2 from 7.8 to 18.2 degrees Mbp, a maximum 2-point LOD score of 3.08 was obtained for the marker D19S586. The region overlaps with the recessive locus DFNB15. CONCLUSION The results underline the heterogeneity of hereditary hearing disorders. Identification of genes can help to reach a better understanding of the molecular mechanism of hearing.

Nichtorganische (funktionelle) Hörstörungen bei Kindern

Nonorganic (functional) hearing loss in children is characterized by hearing loss without a detectable corresponding pathology in the auditory system. It is not an uncommon disease in childhood. Typically, there is a discrepancy between elevated pure tone thresholds and normal speech discrimination in everyday life. We evaluated 85 original publications, 27 reviews and 4 textbook articles. Mean age at diagnosis was 11.3 years. Girls were affected twice as often as boys. Patient histories showed a high prevalence of emotional and school problems. Pre-existing organic hearing loss can be worsened by nonorganic causes. A brainstem audiometry should confirm the diagnosis. The differential diagnosis includes auditory processing disorder, elevated thresholds in mental retardation and auditory neuropathy. We recommend taking a personal history including biographical factors, a psychological assessment including intelligence testing and referral to a child psychiatrist. Prognosis seems to be dependent on the severity of the patients school and/or personal problems. Categorization following the Austen-Lynch model can be a valuable prognostic factor.

Communication skills for interviewing hearing-impaired patients.

completion of the surgical rotation. Evaluation of results and impact The mean Likert score of the Year 4 medical students, an indicator of student satisfaction, was poor, at 29.5 (range: 19–41). Mean Likert scores of the Year 3 students were 29.0 (range: 19–38) for students in the control group and 57.0 (range: 45–60) for students in the study group (p < 0.001). Median TFQ scores for the control and study groups were 58% and 88%, respectively (p < 0.005). This new approach to theatre education helps the student to develop a global appreciation of the surgical patient. Appropriate preoperative preparation and patient interaction help the student to develop links between clinical presentation, investigation, treatment and postoperative care. These links are generic and can be applied to different patients. The results of our study would indicate that this new approach is educationally sound and acceptable to students.

Development and evaluation of the new module ‘communication disorders’ in medical education

Background: Communication disorders are not taught as a self-contained topic in medical education, despite their high incidence and the similarities in the way in which they present clinically. Aims: This article describes the development of an elective subject ‘Phoniatrics and Pediatric Audiology’ covering five topics: hearing, language, and voice as well as psychometric tests and swallowing, with the objective of teaching a basic knowledge of the anatomy, physiology, and pathophysiology of the hearing and language system as well as symptoms, diagnostics, examination, and therapy of communication disorders. It contains theoretical background, practical exercises, and demonstrations of patient examinations. Methods: After initial modifications to the course, a statistical evaluation of the last two half-years in 2006 was performed. Results: The majority of students believe that the subject will be useful in their subsequent studies (94.2%) and medical practice (51.9%). All students affirmed that their expectations had been met by the course and they would choose it again. Conclusions: Uniting several communication disorders within a self-contained topic provides the opportunity to understand pathophysiological principles, similarities, and differences between normal and impaired function of the hearing and language system and voice production. In the authors’ opinion, it is a reasonable inclusion in medical training recognizing the importance of communication in todays service society.

A positive wave at 8 ms (P8) and modified auditory brainstem responses measurement in auditory neuropathy spectrum disorder

OBJECTIVE Auditory neuropathy spectrum disorder (ANSD) is characterized by absent or atypical auditory brainstem responses (ABR), recordable otoacoustic emissions and/or cochlear microphonics. Modification of ABR stimuli is discussed to improve wave V synchronization in ANSD patients. DESIGN Ten ANSD children (seven unilateral) underwent ABR measurement with an alternating stimulus (40.5s(-1)), constant rarefaction and condensation stimuli, a reduced click-rate (11.1s(-1)) and a chirp-stimulus. RESULTS The results showed no remarkably better synchronization with modified stimuli. Whereas higher levels showed no synchronization, reproducible positive waves at 8 ms (P8) at intensities of 65-85 dB were found in six patients with all stimuli. CONCLUSIONS We suggest an ipsilateral auditory origin of the positive potentials at 8 ms. They could be characteristic of synchronization abnormalities in some cases of ANSD.

Ein neuer Genort für eine autosomal-dominante, nichtsyndromale Schwerhörigkeit (DFNA33) liegt auf Chromosom 13q34-qter

By investigation of a German family pedigree with non-syndromic hearing impairment of early onset and autosomal-dominant mode of inheritance, linkage to known DFNA loci was excluded, and the existence of a new locus (DFNA33) was revealed. In a subsequent genomic scan the phenotype was mapped to a 6 cM interval on chromosome 13q34-qter. A maximum two-point lod score of 2.96 was obtained for the marker D13S285 with a maximum lod score in the multipoint analysis of 3.28 at 124.56 cM.