A Multicentre Database for Normative Brainstem Auditory Evoked Potentials (BAEPs) in Children: Methodology for Data Collection and Evaluation.

BACKGROUND: The influence of physiological and methodological factors on recordings of brainstem auditory evoked potentials (BAEPs) is greater in children than in adults. OBJECTIVE: To collect and evaluate BAEP data in normal children, and measure intra- and inter-laboratory variability. METHODS: Seven hundred and fifty unselected BAEP recordings were collected and evaluated from children ranging from neonates to 14-year-olds by eight laboratories in Italy. RESULTS: In newborns, three laboratories showed satisfactory concordance; wave I was more broadly distributed than wave V and IPL I-V. The evaluation of pooled BAEP data from the older children showed that laboratories with age-matched data gave overlapping results; those with unmatched-age data differed significantly. The sound intensities of the laboratories did not significantly affect absolute BAEP latencies or IPLs. Females had shorter latencies than males; the difference was not significant. A single exponential regression model was an adequate but not the best predictor of normal data. CONCLUSIONS: The pooled data were consistent with the physiological maturation of the brainstem acoustic pathway. The BAEPs was reliably normalised using the natural logarithm of age. The differences between Centres were related to sample size, measurement accuracy, and inclusion and selection criteria. SIGNIFICANCE: The creation of multicentre common database from an unmatched data collection is feasible and reliable enough for clinical diagnosis and multicentre clinical research.

The Milan Project: a newborn hearing screening programme.

AIM: Since 1997 a newborn hearing screening programme has been implemented by the U.O. Neurologia-Neurofisiopatologia and Dipartimento di Neonatologia of the Istituti Clinici di Perfezionamento ICP in Milan for both babies with no risk and those at risk of hearing impairment. This programme was named the Milan Project. METHODS: The protocol for no-risk babies consisted of three stages: in the first two stages, newborns were tested with transient click-evoked otoacoustic emissions (TEOAE), in the third one with conventional auditory brainstem responses (ABR). The first TEOAE test was performed by 36 h of age, before discharge, the second one after 15-30 d in case of referral, and the third one, by ABR, for those babies who failed the second TEOAE stage. Newborns at audiological risk were submitted to conventional ABR before the third month of corrected age. Some of this latter population was also submitted to the TEOAE test. The entire tested population (no-risk babies and newborns at audiological risk) consisted of 19 777 babies: 19 290 without risk ("no risk") and 487 at risk ("at risk"). RESULTS: During the course of the Milan Project, hearing impairment (ABR threshold equal to or greater than 40 dB nHL) was identified in 63 newborns (19 from the no-risk and 44 from the at-risk population), with a prevalence of 0.32%. Bilateral hearing impairment (BHI) was found in 33 newborns (10 from the no-risk and 23 from the at-risk population), corresponding to 0.17%. Among infants with bilateral hearing impairment, 30.3% had no risk factors. The prevalence of hearing impairment was determined on days 15-30 after birth. CONCLUSIONS: The results show that the implementation of a hospital-based, universal neonatal hearing screening programme for babies with and without audiological risk is feasible and effective. The effectiveness of the programme has increased as a function of the years since its inception, with a strong decrease in the referral rate. Further improvement is obtained if the TEOAE measurements are repeated in cases of referral scoring before discharge.

Epileptic seizures, epilepsy and epileptic syndromes in newborns: a nosological approach to 94 new cases by the 2001 proposed diagnostic scheme for people with epileptic seizures and with epilepsy.

PURPOSE: To assess the advantages of the 2001 ILAE proposed diagnostic scheme for classification of newborns with epileptic seizures over the 1989 ILAE classification. METHOD: Clinical features, seizure semiology and duration, neurological evaluation, ictal and interictal EEG, brain imaging and outcome at the end of the neonatal period (44 weeks post-conceptional age) of 94 newborns with EEG confirmed seizures were analyzed. The 2001 ILAE classification was applied where possible. RESULTS: Twenty patients died before the end of the neonatal period. In the remaining patients, applying axis 3, we classified 54 newborns as having epileptic seizures that do not require a diagnosis of epilepsy; 14 as symptomatic partial epilepsy; 5 within the neonatal epileptic syndromes and one as benign neonatal seizures (NS). Axis 4 in all newborns provided a valuable tool in order to better define the individual patient. CONCLUSIONS: Compared to the 1989 ILAE classification, which allowed a syndromic diagnosis in only 6/94 patients, the remaining being classified as Epilepsies and Syndromes undetermined whether focal or generalized, the 2001 ILAE diagnostic scheme, applied at the end of the neonatal period, offers a variety of approaches to classification, allowing an early distinction between epilepsy and single or isolated clusters of seizures, with therapeutic and prognostic implications.

Comparison of two methods of TEOAE recording in newborn hearing screening.

This paper summarizes the results of trials performed in two hospitals, comparing the scoring of transient evoked otoacoustic emissions (TEOAEs) on the same neonates and within the same test session, recorded by the fully automatic device EchoScreen (Madsen Electronics/Fischer-Zoth GmbH) and ILO Otodynamics Ltd system. These trials form part of a larger project (Project Sentinel), whose primary aim is to stimulate the creation of new neonatal hearing screening programmes. Four thousand two hundred and forty-eight neonates were tested with both devices (8494 ears), in randomized order. The response scores obtained with the two devices are in full agreement in 98.72% of the tested ears. Considering the recording time, the fully automatic Echo Screen was, on average, about 3.6 times faster than the ILO88, bearing in mind, however, that when using ILO88, the end of the recording is decided by the operator on the basis of some mandatory decision rules.