Minimal Hearing Loss: From a Failure-Based Approach to Evidence-Based Practice.

PURPOSE: A representative sample of the literature on minimal hearing loss (MHL) was reviewed to provide evidence of challenges faced by children with MHL and to establish the need for evidence-based options for early intervention. METHOD: Research articles published from 1950 to 2013 were searched in the Medline database using the keywords minimal hearing loss, unilateral hearing loss, and mild hearing loss. References cited in retrieved articles were also reviewed. RESULTS: In total, 69 articles contained relevant information about pediatric outcomes and/or intervention for unilateral hearing loss, 50 for mild hearing loss, and 6 for high-frequency hearing loss. Six challenges associated with MHL emerged, and 6 interventions were indicated. Evidence indicates that although some individuals may appear to have no observable speech-language or academic difficulties, others experience considerable difficulties. It also indicates that even though children with MHL may appear to catch up in some areas, difficulties in select domains continue into adulthood. CONCLUSIONS: Evidence indicates significant risks associated with untreated MHL. Evidence also demonstrates the need for early intervention and identifies several appropriate intervention strategies; however, no single protocol is appropriate for all children. Therefore, families should be educated about the impact of MHL and about available interventions so that informed decisions can be made.

Transient-evoked otoacoustic emissions from ears with tympanostomy tubes.

OBJECTIVE: Otoacoustic emissions (OAEs) are low-level acoustic signals which emanate from the cochlea and can be recorded in the ear canal. The two types of OAEs are spontaneous and evoked otoacoustic emissions. METHODS: In this retrospective study, transient-evoked otoacoustic emissions (TEOAEs) were measured in 385 ears from 204 children with normal hearing and tympanostomy tubes. RESULTS: The results indicate that, when using the Quick Screen option on the Oto-Dynamics ILO88 Otoacoustic Emission Analyzer, postoperative TEOAEs were present at all measured frequencies in 81% of the ears. The remaining 19% of ears showed the absence of an observable emission at one or more of the measured response frequencies. The overwhelming factor contributing to an absent emission was insufficient stimulus energy at 4 kHz. The use of T-type tympanostomy tubes also appeared to decrease the probabilities obtaining normal TEOAEs in ears with normal peripheral auditory function. The use of grommet-type tympanostomy tubes, the type of middle ear effusion, the age and gender of the child, and the physical volume of the ear canal as measured by tympanometry with the tympanostomy tube patent and in place had negligible effects on the measurement of TEOAEs. CONCLUSIONS: Clinicians must be cautious when interpreting click-evoked TEAOEs if the patient has a T-tube in place and may need to modify this testing to rule out high-frequency hearing loss when using TEOAEs with these patients. For those patients who have tympanostomy tubes and fail to meet the "pass criteria" for TEOAEs at 4 kHz in the Quick Screen option, TEOAE should be repeated either in the Diagnostic mode or by using a 4 kHz tone-burst stimulus centered at 4 kHz to recover the loss of energy in this region due to the high-frequency roll-off of the stimuli used in the Quick Screen option.

Newborn hearing screening: costs of establishing a program.

OBJECTIVE: To evaluate the costs and performance characteristics associated with the start-up phase of Universal Newborn Hearing Screening Programs, one utilizing automated auditory brainstem response (AABR) and the other using transient evoked otoacoustic emissions (TEOAE). STUDY DESIGN: Economic and performance data were collected at the initiation of both screening programs. Data were collected until 1500 newborn infants were screened or until a referral rate for further audiologic evaluation at hospital discharge of less than or equal to 5% was achieved. Data collected included screening pass/fail rates, referral rates and personnel, equipment, and supply utilization. Actual costs of personnel, equipment, and supplies were used. Statistical comparisons of proportions using z-statistic with the one-tailed test and an alpha of 0.01 were made. RESULTS: Screening in the AABR program was performed by neonatal nurses, whereas screening in the TEOAE program was performed by master's level audiologists. The average age at initial screen was 29 hours for TEOAE, and 9.5 hours for AABR. Eighty-four percent of infants was screened within 24 hours in the AABR program, in contrast to 35% in the TEOAE program. Throughout the duration of the study, the referral rate at hospital discharge remained approximately 15% for the TEOAE program. The AABR referral rate began at 8% and was less than 4% at the completion of the study. Pre-discharge total costs for initiating and establishing the programs were US$49,316 for TEOAE and US$47,553 for AABR. Cost per infant screened was US$32.23 and US$33.68, respectively. When post-discharge screening and diagnostic evaluation costs were included, the total cost per infant screened was US$58.07 for TEOAE and US$45.85 for AABR. CONCLUSION: AABR appears to be the preferred method for universal newborn hearing screening. AABR was associated with the lowest costs, achieved the lowest referral rates at hospital discharge, and had the quickest learning curve to achieve those rates.