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Objectives: Neonates admitted to the neonatal intensive care unit (NICU) are at greater risk of permanent hearing loss compared to infants in well mother and baby units. Several factors have been associated with this increased prevalence of hearing loss, including congenital infections (e.g. cytomegalovirus or syphilis), ototoxic drugs (such as aminoglycoside or glycopeptide antibiotics), low birth weight, hypoxia and length of stay. The aetiology of this increased prevalence of hearing loss remains poorly understood. Design: Here we review current practice and discuss the feasibility of designing improved ototoxicity screening and monitoring protocols to better identify acquired, druginduced hearing loss in NICU neonates. Study sample: A review of published literature. Conclusions: We conclude that current audiological screening or monitoring protocols for neonates are not designed to adequately detect early onset of ototoxicity. This paper offers a detailed review of evidence-based research, and offers recommendations for developing and implementing an ototoxicity monitoring protocol for young infants, before and after discharge from the hospital. [ABSTRACT FROM AUTHOR]

Objective:The aims of the present study were to determine the effects of language background on the performance of the pitch pattern sequence test (PPST) and duration pattern sequence test (DPST). As temporal order sequencing may be affected by age and working memory, these factors were also studied.Design:Performance of tonal and non-tonal language speakers on PPST and DPST were compared.Study sample:Twenty-eight native Mandarin (tonal language) speakers and twenty-nine native Malay (non-tonal language) speakers between seven to nine years old participated in this study.Results:The results revealed that relative to native Malay speakers, native Mandarin speakers demonstrated better scores on the PPST in both humming and verbal labeling responses. However, a similar language effect was not apparent in the DPST. An age effect was only significant in the PPST (verbal labeling). Finally, no significant effect of working memory was found on the PPST and the DPST.Conclusion:These findings suggest that the PPST is affected by tonal language background, and highlight the importance of developing different normative values for tonal and non-tonal language speakers. [ABSTRACT FROM PUBLISHER]

Objective: Identification of dead regions is currently based on the results of psychophysical tuning curves (PTC) and the threshold equalizing noise (TEN) test. Summers et al (2003) found poor agreement (56%) between PTC- and TEN test results. Kluk and Moore (2005) argued that these results are explained by beat- and/or combination tone detection. The purpose of this study was to examine the diagnostic dead region relationship between PTCs, modified for beats and/or combination tone detection, and the TEN test with levels calibrated in hearing levels (HL), i.e. TEN[HL]. Design: Twenty-four hearing-impaired ears were evaluated using PTCs and the TEN[HL] test. Results: The results show an agreement of about 75%, depending on the criteria applied, between PTC and the TEN[HL] test. Results also show that PTC probe levels affected diagnostic results in PTCs. Conclusions: Recommended criteria based on the highest agreement score included a PTC shift of 20% and an 8-dB probe elevation above TEN masking levels for the TEN[HL] test. Low agreement scores and level dependent effects in PTCs and the TEN[HL] test suggest that identification of dead regions using a single test is not reliable. [ABSTRACT FROM AUTHOR]

It is well known that two patients suffering from a sensorineural hearing loss with similar audiograms can benefit significantly differently from amplified hearing even if the same settings of the hearing aids are used. The origin of this problem is complex but one part can be caused by the diagnosis itself; all inner-ear hearing losses are assumed similar. Such hypothesis is a simplification that probably leads to suboptimal hearing-aid fitting. For a better understanding of the signal degeneration caused by a cochlear lesion a model layout of the signal transmission in the peripheral hearing organ is presented. This model differentiates between processes in the inner ear caused by the outer hair cells, the inner hair cells, and the endocochlear potential driving the system. The model is intended to predict alteration of the signal caused by different types of cochlear lesions. Ultimately, the model may lead to improved hearing aids and fittings. [ABSTRACT FROM AUTHOR]

The mismatch negativity (MMN) is an electric brain response which is automatically elicited by any discriminable change in a repetitive sound or sound pattern. When this change is made smaller in magnitude, the MMN is attenuated in amplitude, eventually vanishing at around the discrimination threshold. Therefore the MMN provides a unique objective index for a subject or patient's discrimination accuracy. Furthermore, with the MMN, these discrimination thresholds can be separately determined for all the different auditory attributes. Moreover, the individual's ability to discriminate complex sound stimuli and patterns such as different phonemes can also be measured by using the MMN. [ABSTRACT FROM AUTHOR]

Tympanometry is a non-invasive, quick, and inexpensive method for examining the middle-ear function. Its limited value in differentiating otosclerotic from normal middle ears caused researchers to develop new methods for evaluation of middle ears. Resonant frequency had been found to be higher in otosclerotic middle ears than normals. We conducted multiple-frequency tympanometry measurements in 25 surgically confirmed otosclerotic ears and 100 normal ears. Mean middle-ear resonant frequency for the otosclerotic group was found to be 1190 Hz and mean middle-ear resonant frequency of the control group was 934.6 Hz (p<0.001). With a cut off value of 1025 Hz (based on 95% confidence interval), sensitivity was 80% and specificity was 82%. The present findings confirm the advantage of the resonant frequency estimation over conventional tympanometry in detecting middle-ear status and mechanics in patients with otosclerosis. As a conclusion, detecting resonant frequency when evaluating patients for otosclerosis must be an essential part of examination. Nevertheless, further investigation is necessary for better diagnosis of otosclerosis preoperatively. [ABSTRACT FROM AUTHOR]