Faster automatic ASSR detection using sequential tests.

Objective: Objective Response Detection (ORD) can be used for auditory steady-state response (ASSR) detection. In conventional ORD methods, the statistical tests are applied at the end of data collection ('single-shot tests'). In sequential ORD methods, statistical tests are applied repeatedly, while data is being collected. However, repeated testing can increase False Positive (FP) rates. One solution is to infer that response is present only after the test remains significant for a predefined number of consecutive detections (NCD). Thus, this paper describes a new method for finding the required NCD that control the FP rate for ASSR detection.Design: NCD values are estimated using Monte Carlo simulations.Study sample: ASSR signals were recorded from 8 normal-hearing subjects.Results: The exam time was reduced by up to 38.9% compared to the single-shot test with loss of approximately 5% in detection rate. Alternatively, lower gains in time were achieved for a smaller (non-significant) loss in detection rate. The FP rates at the end of the test were kept at the nominal level expected (1%).Conclusion: The sequential test strategy with NCD as the stopping criterion can improve the speed of ASSR detection and prevent higher than expected FP rates.

A systematic review and meta-analysis of extratympanic electrocochleography in Ménière's disease diagnosis.

Objective: Determine whether a combination of electrocochleography determined summating/action potential (SP/AP) ratio and other audiological measurements has greater sensitivity and specificity than that achieved with electrocochleography SP/AP ratio alone in diagnosing definite Ménière's Disease. Design: Systematic review and meta-analysis. Study sample: Pubmed, Cochrane Library, and Web of Science were searched using search terms "electrocochleography", "ECochG, ,"ECoG", "Ménière's Disease", and "Idiopathic Endolymphatic Hydrops". Inclusion criteria were extratympanic electrocochleography methodology, English language publication between January 2002 and December 2017, and the 1995 American Academy of Otolaryngology and Head and Neck Surgery Ménière's disease diagnostic criteria. Five articles satisfied inclusion criteria and were sufficiently detailed for aggregate quantitative analysis of SP/AP ratio (315 subjects) and combination audiological measures (113 subjects). Results: The diagnostic sensitivity and specificity of the SP/AP amplitude ratio was 47.6% and 83.8% and of combination diagnostic measures 63.5% and 89.3%, respectively. Point estimates of sensitivity (p = 0.248) and specificity (p = 0.969) and the summary Receiver Operator Characteristic Curve (p = 0.407) were not statistically significant. Conclusion: Statistically, combination diagnostic measures do not result in greater accuracy of definite Ménière's disease diagnosis compared to the SP/AP amplitude ratio alone. However, given the small sample size further studies are recommended to arrive at a definitive conclusion.

Accuracy of otoacoustic emissions, and automated and diagnostic auditory brainstem responses, in high-risk infants.

OBJECTIVES: This study aimed to compare the diagnostic reliabilities of transient evoked otoacoustic emissions, automated auditory brainstem responses and brainstem auditory evoked responses for detecting hearing loss, and to use the information regarding hearing level of automated auditory brainstem responses for planning rehabilitation. METHODS: A total of 144 high-risk infants (288 ears) completed the 3 hearing tests. The sensitivity and specificity of otoacoustic emissions and automated auditory brainstem responses were compared using the chi-square test. RESULTS: Automated auditory brainstem response was the most reliable test of hearing levels, with a sensitivity of 91.7 per cent and specificity of 92.1 per cent; the sensitivity of otoacoustic emissions was 78.7 per cent and the specificity was 88.8 per cent. CONCLUSION: Automated auditory brainstem responses have acceptably high sensitivity and specificity. Additionally, the hearing level from automated auditory brainstem responses can help the screeners explain to the parents the importance of further diagnosis and rehabilitation.

The frequency-following response (FFR) to speech stimuli: A normative dataset in healthy newborns.

The Frequency-Following Response (FFR) is a neurophonic auditory evoked potential that reflects the efficient encoding of speech sounds and is disrupted in a range of speech and language disorders. This raises the possibility to use it as a potential biomarker for literacy impairment. However, reference values for comparison with the normal population are not yet established. The present study pursues the collection of a normative database depicting the standard variability of the newborn FFR. FFRs were recorded to /da/ and /ga/ syllables in 46 neonates born at term. Seven parameters were retrieved in the time and frequency domains, and analyzed for normality and differences between stimuli. A comprehensive normative database of the newborn FFR is offered, with most parameters showing normal distributions and similar robust responses for /da/ and /ga/ stimuli. This is the first normative database of the FFR to characterize normal speech sound processing during the immediate postnatal days, and corroborates the possibility to record the FFRs in neonates at the maternity hospital room. This normative database constitutes the first step towards the detection of early FFR abnormalities in newborns that would announce later language impairment, allowing early preventive measures from the first days of life.

Normalization of Bone Conduction Auditory Brainstem Evoked Responses in Normal Hearing Individuals.

OBJECTIVES: Auditory brainstem responses (ABR) are used to evaluate the peripheral and central functions of the auditory tract. Air and bone-conduction auditory stimuli are used to evaluate the type and degree of hearing loss. The wave latencies and interpeak latencies (IPLs) are the important diagnostic data in ABR tests. Gender and age of the patients are some of the factors affecting these latencies. This study investigated the effects of age and gender on the wave and IPLs of bone-conduction ABR. MATERIALS AND METHODS: One hundred healthy individuals (50 women and 50 men) aged between 10 and 60 years were enrolled into this study, and both ears of all subjects (200 ears total) were included in the assessments. Based on their age, the subjects were equally divided into five groups, and each group consisted of 10 men and 10 women. RESULTS: The findings showed a significant difference in wave latencies and IPLs between the two genders (p<0.05). Depending on stimulus intensity, wave latencies also showed statistically significant differences between the age groups (p<0.05). However, no significant difference was noted between the age groups regarding IPLs. CONCLUSION: Normative values that covered wave latencies and IPLs evoked at stimulus intensities of 50, 30, and 10 dB nHL were established for the clinical use and use as a reference for the bone-conduction ABR testing procedure.

[Is the current level of investigation for vestibular schwannoma reasonable?] / Utredningsnivån av vestibulära schwannom måste bli rimlig - Nationella riktlinjer behövs.

The main aim of this study was to evaluate if the level of investigation with MRT or BRA (Brainstem Response Audiometry) is adequate in relation to the number of vestibular schwannomas (VS) found in a county like  Dalarna (277 000 inhabitants) in Sweden. The reason to investigate was asymmetrical sensorineural hearing loss (ASHL) defined as a one-sided hearing loss exceeding 10 dB compared to the contralateral side. Between 2007-2014 a total of 55 patients (incidence 2.5/100 000) were diagnosed with a VS in the county. The local ENT department found two thirds of these patients. In the year of 2010, MRT was advocated by SBU (Swedish Agency for Health Technology Assessment and Assessment of Social Services) as the primary step of investigation. During 2011-2014, 981 patients underwent MRT and 482 patients BRA, because of ASHL. Seventeen VS were found, meaning that 58 MRT and 29 BRA were conducted to find one VS. According to earlier studies, only one third of VS show growth tendency. Taking this into consideration, 174 (58 × 3) investigations with MRT will only diagnose approximately 1 patient with a growing VS. We therefore question today's level of investigation and ask for new uniform recommendations on how to investigate for VS in cases of ASHL.

A controlled comparison of auditory steady-state responses and pure-tone audiometry in patients with hearing loss.

We performed a prospective interventional study to evaluate correlations between hearing thresholds determined by pure-tone audiometry (PTA) and auditory steady-state response (ASSR) testing in two types of patients with hearing loss and a control group of persons with normal hearing. The study was conducted on 240 ears-80 ears with conductive hearing loss, 80 ears with sensorineural hearing loss, and 80 normal-hearing ears. We found that mean threshold differences between PTA results and ASSR testing at different frequencies did not exceed 15 dB in any group. Using Pearson correlation coefficient calculations, we determined that the two responses correlated better in patients with sensorineural hearing loss than in those with conductive hearing loss. We conclude that measuring ASSRs can be an excellent complement to other diagnostic methods in determining hearing thresholds.

[Impact of the Overlap Region Between Acoustic and Electric Stimulation]. / Einfluss des Überlappungsbereichs zwischen akustischer und elektrischer Stimulation.

Patients with residual hearing in the low frequencies and ski-slope hearing loss with partial deafness at medium and high frequencies receive a cochlear implant treatment with electric-acoustic stimulation (EAS, "hybrid" stimulation). In the border region between electric and acoustic stimulation a superposition of the 2 types of stimulation is expected. The area of overlap is determined by the insertion depth of the stimulating electrode and the lower starting point of signal transmission provided by the CI speech processor. The study examined the influence of the variation of the electric-acoustic overlap area on speech perception in noise, whereby the width of the "transmission gap" between the 2 different stimulus modalities was varied by 2 different methods. The results derived from 9 experienced users of the MED-EL Duet 2 speech processor show that the electric-acoustic overlapping area and with it the crossover frequency between the acoustic part and the CI should be adjusted individually. Overall, speech reception thresholds (SRT) showed a wide variation of results in between subjects. Further studies shall investigate whether generalized procedures about the setting of the overlap between electric and acoustic stimulation are reasonable, whereby an increased number of subjects and a longer period of acclimatization prior to the conduction of hearing tests deemed necessary.

Auditory neuropathy spectrum disorder (ANSD) in referrals from neonatal hearing screening at a well-baby clinic.

UNLABELLED: Auditory neuropathy spectrum disorder (ANSD) is a particular kind of hearing disorder characterised by normal outer hair cell function and abnormal or absent auditory brain stem responses. Little data are available regarding the prevalence of this condition in healthy newborns. We performed a retrospective medical records review of 791 referrals from universal neonatal hearing screening (UNHS) at a well-baby clinic to investigate the prevalence of ANSD. Hearing screening was performed by automated auditory brain stem response (ABR) testing. A diagnosis of ANSD was established when ABR tracings were absent in the presence of otoacoustic emissions and/or a cochlear microphonic. Amongst 201 infants with confirmed congenital hearing loss, 13 infants were diagnosed with ANSD. The condition was unilateral in six and bilateral in seven infants. A risk factor for hearing loss could be identified in three infants. Abnormalities on magnetic resonance imaging were found in six infants; five of them had cochlear nerve deficiency. CONCLUSION: The prevalence of ANSD was 6.5 % amongst well babies with confirmed congenital hearing loss identified through UNHS. The estimated incidence of ANSD in our population of newborns at the well-baby clinic was 0.09/1000 live births. Magnetic resonance revealed an underlying anatomical abnormality in about half of the patients. WHAT IS KNOWN: • Auditory neuropathy dyssynchrony spectrum disorder (ANSD) is a particular form of hearing loss, mostly encountered in neonatal intensive care unit (NICU) graduates. • Little data are available on the prevalence and risk factors for ANSD in healthy newborns. What is new: • The estimated prevalence of ANSD in healthy newborns is 0.09/1000 live births. • In about half of the healthy newborns with ANSD, a structural abnormality was detected on magnetic resonance imaging of the posterior fossa/brain.

[Compliance with current standards for the early detection of neonatal hearing loss]. / Cumplimiento de la normatividad vigente para la detección temprana de la hipoacusia neonatal.

OBJECTIVE: Assessing compliance with the section "Assessment of hearing" stipulated in the Technical Standard to Detect Alteration in children aged less than 10 years-old in Bogota. METHODS: This was a cross-sectional study which involved reviewing the medical records of all children born between July 1st and December 31st 2010 in two healthcare institutions in Bogota. Records were selected in which any of the following risk factors appeared: neonatal hyperbilirubinaemia involving phototherapy, neonatal exposure to ototoxic substances and/or <1.500 gr low birth weight. It was also ascertained whether children had been referred to an auditory evoked potential test as the prescribed screening test for neonatal hearing, as stipulated in mandatory Colombian technical standards for detecting abnormal growth and developmental in children aged less than ten years-old. RESULTS: Neither of the two institutions was making the aforementioned referral test. DISCUSSION: The results indicated significant difficulties in adherence to the protocol for the early detection of hearing loss regarding pertinent/current neonatal Colombian regulations.

Aging degrades the neural encoding of simple and complex sounds in the human brainstem.

BACKGROUND: Older adults, with or without normal peripheral hearing sensitivity, have difficulty understanding speech. This impaired speech perception may, in part, be due to desynchronization affecting the neural representation of acoustic features. Here we determine if phase-locked neural activity generating the brainstem frequency-following response (FFR) exhibits age-related desynchronization and how this degradation affects the neural representation of simple and complex sounds. PURPOSE: The objectives of this study were to (1) characterize the effects of age on the neural representation of simple tones and complex consonant-vowel stimuli, (2) determine if sustained and transient components of the FFR are differentially affected by age, and (3) determine if the inability to encode a simple signal predicts degradation in representation for complex speech signals. RESEARCH DESIGN: Correlational. STUDY SAMPLE: Thirty four adults (aged 22-77 yr) with hearing thresholds falling within normal limits. DATA COLLECTION AND ANALYSIS: Stimuli used to evoke FFRs were 1000 Hz tone bursts as well as a consonant-vowel /da/ sound. RESULTS: The neural representation of simple (tone) and complex (/da/) stimuli declines with advancing age. Tone-FFR phase coherence decreased as chronological age increased. For the consonant-vowel FFRs, transient onset and offset response amplitudes were smaller, and offset responses were delayed with age. Sustained responses at the onset of vowel periodicity were prolonged in latency and smaller in amplitude as age increased. FFT amplitude of the consonant-vowel FFR fundamental frequency did not significantly decline with increasing age. The ability to encode a simple signal was related to degradation in the neural representation of a complex, speechlike sound. Tone-FFR phase coherence was significantly related to the later vowel response components but not the earlier vowel components. CONCLUSIONS: FFR components representing the tone and consonant-vowel /da/ stimulus were negatively affected by age, showing age-related reductions in response synchrony and amplitude, as well as prolonged latencies. These aging effects were evident in middle age, even in the absence of significant hearing loss.

Cumplimiento de la normatividad vigente para la detección temprana de la hipoacusia neonatal / Compliance with current standards for the early detection of neonatal hearing loss

Objetivo Evaluar el cumplimiento del apartado de "Valoración de la Capacidad Auditiva" estipulado en la Norma Técnica para la Detección de las Alteraciones en el menor de 10 años en la ciudad de Bogotá, Colombia. Método Se realizó un estudio transversal. Se revisaron las historias clínicas de todos los niños nacidos entre el 01 de julio y el 31 de diciembre de 2010, en dos instituciones de salud de la ciudad de Bogotá. Se seleccionaron aquellas en las que se presentaba cualquiera de los siguientes factores de riesgo: hiperbilirrubinemia neonatal con requerimiento de fototerapia, exposición neonatal a ototóxicos, bajo peso al nacer (<1 500 gramos) y se verificó la remisión a Potenciales Auditivos Evocados como prueba de detección de la hipoacusia neonatal de acuerdo a lo estipulado de manera obligatoria en la Norma Técnica para la Detección de las Alteraciones de Crecimiento y Desarrollo en el Menor de Diez Años. Resultados En ninguna de las dos instituciones se realizó la remisión a la prueba mencionada. Discusión Los resultados del estudioindican graves dificultades en la adherencia al protocolo de detección temprana de la hipoacusia neonatal vigente en la normatividad Colombiana.

Objective Assessing compliance with the section "Assessment of hearing" stipulated in the Technical Standard to Detect Alteration in children aged less than 10 years-old in Bogota. Methods This was a cross-sectional study which involved reviewing the medical records of all children born between July 1st and December 31st 2010 in two healthcare institutions in Bogota. Records were selected in which any of the following risk factors appeared: neonatal hyperbilirubinaemia involving phototherapy, neonatal exposure to ototoxic substances and/or <1.500 gr low birth weight. It was also ascertained whether children had been referred to an auditory evoked potential test as the prescribed screening test for neonatal hearing, as stipulated in mandatory Colombian technical standards for detecting abnormal growth and developmental in children aged less than ten years-old. Results Neither of the two institutions was making the aforementioned referral test. Discussion The results indicated significant difficulties in adherence to the protocol for the early detection of hearing loss regarding pertinent/current neonatal Colombian regulations.

Auditory steady-state responses in normal hearing adults: a test-retest reliability study.

The test-retest reliability of the auditory steady-state response (ASSR) has received limited attention. Therefore, the aim was to assess the test-retest reliability of an 80-Hz multiple-ASSR system in normal-hearing subjects by a comprehensive set of statistical methods. Twenty-nine participants (15 females) aged between 18 and 30 years contributed to two sessions (test-retest), and the ASSR thresholds were determined with a descending search protocol using a 10-dB precision. The test-retest reliability was assessed by a three-layered approach which consisted of Pearson product-moment correlation, analysis of variance (ANOVA), and standard error of measurement (SEM). The correlations for ASSR thresholds ranged from poor (0.34) for 500 Hz CF to moderate (0.55) for 1000, 2000, and 4000 Hz CF. A two-way ANOVA of the difference scores (ASSR threshold minus behavioral threshold) demonstrated no significant difference between test and retest. The SEM determined the normal tolerance for clinical error of repeated thresholds and the ASSR SEM values fell well within +/-10 dB HL. This investigation shows that the multiple ASSR-technique produces a clinically acceptable test-retest reliability for normal-hearing adults.

The frequency of auditory neuropathy detected by universal newborn hearing screening program.

OBJECTIVE: Auditory neuropathy/auditory dyssynchrony (AN/AD) has become a well-accepted clinical entity. The combined use of oto-acoustic emissions (OAEs) and auditory brainstem response (ABR) testing in the universal newborn hearing screening (UNHS) has led to the easy recognition of this disorder. Although, we are now able to diagnose AN/AD reliably, little is known about its epidemiology, etiology, and especially the frequency of its occurrence. The primary goal of this study was to determine the frequency of AN/AD in the Western Anatolian region of Turkey. The secondary goal was to compare the detection rate of AN/AD before and after the implementation of the UNHS in the audiology department of Dokuz Eylul University Hospital. METHOD: Between 2005 and 2007, among the 23,786 newborns who were screened by automated click evoked oto-acoustic emissions (a-CEOAE) and automated auditory brainstem responses (a-ABRs), 2236 were referred to our department. All necessary audiological tests were performed for all the referred newborns. Among them, babies with deficient or abnormal ABR in combination with normal OAEs were considered as having AN/AD. These babies were evaluated with additional diagnostic audiological tests. Furthermore, comparison of the incidence of children diagnosed with AN/AD before and after the implementation of UNHS in our audiology department was also performed. RESULTS: Among the referred newborns, 65 had abnormal or deficient ABR test results. Ten of these 65 newborn babies (mean diagnostic age: 5.7 months) with hearing impairment showed electrophysiological test results that were consistent with AN/AD. The frequency of AN/AD in these 65 children with hearing loss was 15.38%. Moreover, the frequency of AN/AD within UNHS was found to be 0.044%. Seven of the 10 babies with AN/AD had hyperbilirubinemia as a risk factor, which is a high rate to be emphasized. On the other hand, the retrospective investigation of children diagnosed with AN/AD in the same audiology department between 1999 and 2005 (i.e. before the implementation of UNHS) revealed only 7 children, with an average diagnostic age of 34 months. CONCLUSION: After implementing the UNHS, the incidence of AN/AD in the audiology department increased from 1.16 to 4.13. Furthermore, the age of diagnosis of AN/AD decreased from 34 months to 5.7 months. This study shows that AN/AD, when screened, is a comparatively common disorder in the population of hearing-impaired infants. While newborn hearing screening provides early detection of babies with hearing loss, it also helps to differentiate AN/AD cases when the screening is performed with both a-ABR and automated oto-acoustic emission (a-OAE) tests. Thus, the routine combined use of a-ABR and a-OAE tests in UNHS programs, especially for the high-risk infants, can provide better detection of newborns with AN/AD. Furthermore, hyperbilirubinemia is merely an association and maybe etiologically linked.

Universal newborn hearing screening programs in Italy: survey of year 2006.

CONCLUSION: Our results suggest a rapid diffusion of newborn hearing screening programs in Italy and indicate that three conditions seem to play a crucial role in the implementation of Universal Newborn Hearing Screening (UNHS) programs: the size (>800 births/year) and location (metropolitan urban areas) of the hospital, and the presence of an audiologist in the UNHS coordinating team. OBJECTIVES: The aim of this paper is to provide data on the degree of implementation and coverage of UNHS programs in Italy. MATERIALS AND METHODS: Data were collected through a Screening Survey Questionnaire that was sent to all birthing hospitals active in Italy in 2006 and was filled in by the chief of the hospital or by the UNHS program coordinator. RESULTS: In Italy UNHS coverage had undergone a steep increase from 29.3% in 2003 (156,048 newborns screened) to 48.4% in 2006 (262,103 screened). The majority of UNHS programs were implemented in the two most economically developed areas, i.e. in the north-west area (79.5%, 108,200 of 136,109 births), and in the north-east area (57.2%, 52,727 of 92,133 births), while a limited diffusion still remains in some areas, typically in the islands (11.3%, 7158 of 63,460 births).

The influence of the detection paradigm in recording auditory steady-state responses.

OBJECTIVES: The purpose of this study was to evaluate the risks of uncontrolled use of an objective detection criterion in recording auditory steady-state responses (ASSRs). The influence of decisions such as when to accept a response and stop the recording was assessed by analyzing the number of false- and true-detected responses. DESIGN: A large sample of 500 multiple-stimulus ASSR recordings of normal-hearing and hearing-impaired adults and babies was processed offline. Three types of detection paradigms were evaluated. A first type had a fixed recording length with significance testing after the last sweep. A second type allowed a variable recording length and implied sequential application of the statistical decision criterion. The recording was stopped after significance was reached for y consecutive sweeps. The third type was analogous to the second, with the additional requirement of a minimum of eight recorded sweeps. Furthermore, the effect of significance level and averaging procedure were assessed. Error rates were calculated for the different detection paradigms at eight control frequencies. At the signal frequencies, detection rates and recording times were determined, keeping the error rates fixed. Moreover, ASSR thresholds were compared for a selection of detection paradigms. RESULTS: When a variable recording length was allowed and a significance level of p = 0.05 was applied, the error rate increased to unacceptable levels because of the effect of repeated testing. The error rate decreased as the required number of consecutive significant sweeps increased and approximated 5% only when eight consecutive significant sweeps were required (with a maximum of 32 recorded sweeps). With an error rate of 5%, the highest detection rate was associated with a fixed recording length of 32 sweeps combined with weighted averaging. A substantial decrease in detection rate was noted when less than 24 sweeps were recorded per intensity. All paradigms with a variable recording length had rather comparable detection rates and recording times. With an error rate of only 1%, small responses could not be distinguished from the noise. The reduction in recording time using a variable instead of a fixed recording length was very limited when a conventional multiple-stimulus approach was used. Test duration would be reduced considerably when the test set-up would allow an independent presentation and recording of the eight signals and responses. Differences in overall detection rate had a small effect on the ASSR thresholds. CONCLUSIONS: The error rate, detection rate, and recording time can improve or deteriorate significantly, even with small adaptations of the detection protocol. When a variable recording length is allowed, the acceptance criterion of the statistical test needs to be adjusted to ensure a tolerable error rate. However, most commercial devices do not offer this option. Then, it is advisable to use a fixed recording length and to judge the significance of the responses at the end of the recording. Although response detection is objective, the measurement protocol has to be well-considered and a critical approach is required when interpreting the responses.

EVestG: responses in depressed patients.

Depression is a mood disorder characterized by a sustained period of low mood or loss of interest or pleasure in activities. Dysfunction of the limbic system is implicated in depression. Different areas of this system have bidirectional links with the vestibular nucleus. The diagnosis of depression is subjective. Electrovestibulography (EVestG) might be able to assist in the diagnosis of depression in a more objective way. A dynamic measure of the excitatory (ipsilateral) responses during the background, acceleration and deceleration phases of an active tilt are compared with a small group (n=5) of depressive patients and age matched controls (n=10).

Ligurian experience on neonatal hearing screening: clinical and epidemiological aspects.

AIM: Early identification and rehabilitation of newborns with congenital hearing impairment (HI) by Universal Neonatal Hearing Screening (UNHS). METHODS: The neonatal population was divided into two groups: babies with No Audiological Risk (NAR), and babies With Audiological Risk (WAR). NAR neonates underwent OAE testing, and in case of a doubtful (Refer) result, ABR testing was carried out. All WAR newborns underwent ABR testing within the third month of life. RESULTS: Between February 1, 2002 and December 31, 2004, UNHS was carried out on 32 502 newborns at the 13 regional birth centres, representing 98.7% of the whole regional neonatal population. The prevalence of HI in the population we tested was estimated at about 1 per thousand, while Bilateral Hearing Impairment (BHI) was estimated at 0.65 per thousand. A 3.7% prevalence of HI and a 2.8% prevalence of BHI was observed among the WAR population. Median age at the end of the diagnostic procedures was 6.7 months in the WAR population and 6.9 months in the NAR population. CONCLUSIONS: Our project is based on two levels of testing, which resulted in a 0.28% false-positive rate with 100% sensitivity and 99% specificity. Our screening is the first Italian experience that has been extended to a whole region and the results prove that regional neonatal hearing screening is feasible.

Summating potential-action potential waveform amplitude and width in the diagnosis of Menière's disease.

OBJECTIVES: It has been suggested that analyzing the width and amplitude of the summating potential-action potential (SP-AP) waveforms can increase the sensitivity of electrocochleography. The objective of this study was to evaluate the ratio of SP to AP amplitude (SP/AP) and SP-AP waveform width, as well as the AP latency difference to condensation and rarefaction clicks, for the diagnosis of Menière's disease. STUDY DESIGN: This was a prospective, controlled study. METHODS: We used transtympanic electrocochleography to evaluate 21 patients with definite Menière's disease and 19 normal-hearing patients with other cochleovestibular disorders, comparing SP/AP, AP latency difference, and SP-AP waveform widths as well as calculating the diagnostic sensitivity of these parameters. RESULTS: Mean SP-AP waveform width was 1.89 ms in the study group and 1.58 ms in the control group. Mean SP/AP was 0.37 in the study group and 0.22 in the control group. The mean product of SP-AP waveform width and SP/AP was 75.26 ms% in the study group and 34.60 ms% in the control group. Mean AP latency difference was 0.13 ms in the study group and 0.07 ms in the control group. For the parameters evaluated, the differences between the groups were statistically significant. In the study group, the sensitivities for the width of the SP-AP waveform, the SP/AP, and the AP latency difference were 33.3%, 52.4%, and 23.8%, respectively. CONCLUSIONS: The use of the parameters evaluated did not increase the sensitivity of the electrocochleography, whether used in isolation or in conjunction with the SP/AP. Determining SP/AP presented the greatest sensitivity.

Epidemiology of early hearing loss detection in Hawaii.

OBJECTIVE: Universal Newborn Hearing Screening began in 2 Honolulu hospitals in 1992, and by 1999, all 14 civilian birthing facilities in Hawaii were providing screening. Examination of 1998 Hawaii data indicated that approximately 13% of infants who did not pass initial hearing screening in the hospital did not return for the indicated follow-up. The purpose of this study was to determine the epidemiologic profile of infants who were born in 1999 and did not return for follow-up. METHODS: A population-based, cohort study of the hearing screening completion rates among the 13 civilian birthing facilities in Hawaii that provided data to the Department of Health was conducted. Analysis included a bivariate analysis of the demographic characteristics of infants who completed the screening/follow-up process compared with those who did not and logistic regression modeling to ascertain the demographic profile of infants at high risk for being lost to follow-up. RESULTS: Of 12 456 infants, hearing screening data could be linked to the birth certificate file, and a final disposition regarding completion of the screening/follow-up process was determined for 10 328 (83%). Less than 2% (n = 176) of the linked infants failed to complete the screening/follow-up procedures. Low birth weight and white infants and infants born to women who had not completed high school were approximately twice as likely not to complete the screening as were their normal birth weight or nonwhite counterparts. CONCLUSIONS: Failure to complete the hearing screening follow-up may be related to cultural differences that have been previously reported in other maternal and child health studies of the diverse populations in Hawaii. The results of this study will allow the Hawaii Newborn Hearing Screening Program to target its efforts and limited resources toward infants who are at higher risk of not completing the screening and who may need special attention to encourage their mothers to complete the screening process, and to move quickly with rescreening infants whose initial tests are positive so that infants are not lost to follow-up.