Effects of Unilateral Hearing Loss on Speech-Evoked Auditory Brainstem Responses and Reading: A Preliminary Study.

PURPOSE: The purpose of this study was to determine whether the speech-evoked auditory brainstem responses (sABRs) obtained by stimulating the ear with normal sensitivity in children with unilateral hearing loss (UHL) were different from that of children with normal hearing (NH), and to explore correlations between the sABR findings and measures of reading. METHOD: Eleven children with UHL and 11 children with NH were tested via the BioMARK sABR protocol using the syllable /da/; latency and amplitudes of Waves V, A, C, D, E, F, and O were measured. Participants also were tested on the Phonemic Synthesis Test (PST) and the Woodcock Reading Mastery Test-Revised (WRMT-R), particularly the Reading Readiness, Basic Skills, and Comprehension subtests. RESULTS: Multivariate analysis of variance testing showed a significantly higher amplitude for Wave A for the NH group as compared to the UHL group. Separate ANOVAs also found significantly lower scores for the UHL group compared to the NH group on Basic Skills and Comprehension subtests of the Woodcock. Significant positive Spearman rho correlations were found for the UHL group between wave amplitudes for V, A, and O and the Reading Readiness score, and between wave amplitudes for V, A, D, and O and the Reading Comprehension score. A significant correlation also was found between the Total Reading score and wave amplitudes for V and A. No such correlations were found between wave amplitude and Woodcock scores for the NH group. Further testing of the UHL data found significant relationships between the pure-tone average of the hearing loss ear and the Basic Skills, Comprehension, and Total Reading scores from the WRMT-R. There was also a significant correlation between the PST score and Wave C amplitude. CONCLUSION: There may be a connection between speech encoding and measures of reading in children with UHL.

Three Cases of Recovery from Sensorineural Hearing Loss in the First Year of Life: Implications for Monitoring and Management.

BACKGROUND: Three infants with different risk factors, behavioral and physiologic audiometric histories, and diagnoses were fit with amplification between 3 and 8 months of age. Two of the three met criteria for cochlear implantation. PURPOSE: This article aims to heighten awareness of the rare possibility of recovery from sensorineural hearing loss in infants with varying histories and emphasize the importance of a full diagnostic test battery in all infants diagnosed with sensorineural hearing loss every 3 months until objective and subjective thresholds are stable to ensure appropriate intervention. RESEARCH DESIGN: Case reports. RESULTS: All three infants demonstrated improvement or full recovery of hearing and cochlear function by approximately 12 months old. Their change in hearing was discovered due to frequent follow-up and/or caregiver report. One of these infants was tentatively scheduled to have cochlear implant surgery 2 months later. CONCLUSION: Appropriate early intervention for infants with hearing loss is critical to ensure maximum accessibility to speech and language cues. The Federal Drug Administration approves cochlear implantation in infants as young as 12 months. When providing audiometric management of infants with sensorineural hearing loss, it is imperative to conduct a full diagnostic test battery every 3 months (including tympanometric, acoustic reflex, and otoacoustic emission measurement) until objective and subjective thresholds are stable. There was no apparent pattern of factors to predict that the infants highlighted in these cases would recover. Discussion among pediatric audiologists and otologists and comparison of data from clinics across the U.S. is needed to identify predictive patterns and determine appropriate, consistent monitoring of infants with sensorineural hearing loss.

Detection of Deafness in Puppies Using a Hand-Held Otoacoustic Emission Screener.

The purpose of this study was to evaluate the use of a hand-held otoacoustic emissions screener to detect deafness in puppies. Specifically, distortion product otoacoustic emissions were recorded from 34 puppies (both sexes) of a variety of breeds, from 6-10 wk of age, and the results were compared to brainstem auditory evoked responses (BAER) recorded from the same puppies. Recordings were obtained from both ears in awake or lightly anesthetized puppies, and the results from each ear were compared. In all 62 ears that had normal BAERs, the distortion product otoacoustic emissions screener gave a response of "Pass." The three puppies that had flat BAER recordings in one or both ears provided a screener result of "Refer." In two ears with unusual BAERs (waveforms with reduced amplitudes and prolonged latencies) and a "Refer" response from the screener, there was compacted debris in one external ear canal, and the other ear canal was normal. The screener technology has proven application in human infants and is an attractive alternative to BAER testing in puppies because of expense and ease of use.

Serial auditory-evoked potentials in the diagnosis and monitoring of a child with Landau-Kleffner syndrome.

BACKGROUND: A boy, aged 2 1/2 yr, experienced sudden deterioration of speech and language abilities. He saw multiple medical professionals across 2 yr. By almost 5 yr, his vocabulary diminished from 50 words to 4, and he was referred to our speech and hearing center. PURPOSE: The purpose of this study was to heighten awareness of Landau-Kleffner syndrome (LKS) and emphasize the importance of an objective test battery that includes serial auditory-evoked potentials (AEPs) to audiologists who often are on the front lines of diagnosis and treatment delivery when faced with a child experiencing unexplained loss of the use of speech and language. RESEARCH DESIGN: Clinical report. RESULTS: Interview revealed a family history of seizure disorder. Normal social behaviors were observed. Acoustic reflexes and otoacoustic emissions were consistent with normal peripheral auditory function. The child could not complete behavioral audiometric testing or auditory processing tests, so serial AEPs were used to examine central nervous system function. Normal auditory brainstem responses, a replicable Na and absent Pa of the middle latency responses, and abnormal slow cortical potentials suggested dysfunction of auditory processing at the cortical level. The child was referred to a neurologist, who confirmed LKS. At age 7 1/2 yr, after 2 1/2 yr of antiepileptic medications, electroencephalographic (EEG) and audiometric measures normalized. Presently, the child communicates manually with limited use of oral information. CONCLUSIONS: Audiologists often are one of the first professionals to assess children with loss of speech and language of unknown origin. Objective, noninvasive, serial AEPs are a simple and valuable addition to the central audiometric test battery when evaluating a child with speech and language regression. The inclusion of these tests will markedly increase the chance for early and accurate referral, diagnosis, and monitoring of a child with LKS which is imperative for a positive prognosis.

A comparison of video versus conventional visual reinforcement in 7- to 16-month-old infants.

PURPOSE: To compare response patterns to video visual reinforcement audiometry (VVRA) and conventional visual reinforcement audiometry (CVRA) in infants 7-16 months of age. METHOD: Fourteen normal-hearing infants aged 7-16 months (8 male, 6 female) participated. A repeated measures design was used. Each infant was tested with VVRA and CVRA over 2 different sessions. The total number of head turns prior to habituation, hit rate (response consistency), false alarm rate, and sensitivity for each reinforcement condition were evaluated. RESULTS: No significant differences were found between the 2 reinforcement methods for total number of head turns, hit rate, false alarm rate, or sensitivity. Overall, results showed no difference between the 2 reinforcer conditions in infants 7-16 months of age. CONCLUSION: The results of the present study suggest that infants in the 7- to 16-month-old age range respond similarly to VVRA and CVRA as measured by response consistency and false alarm rate. VVRA is, therefore, a viable option for testing hearing in infants. However, prior to clinical implementation, the effectiveness of VVRA should be explored in infants with hearing loss.