[Implantation of a program for the early detection of neonatal hearing loss]

Evaluation of very low birth weight (≤ 1,500 g) as a risk indicator for sensorineural hearing loss

INTRODUCTION AND OBJECTIVE

Hearing plays an essential role in the acquisition, development and maintenance of the properties of the speech and language. Birth weight is an indicator of biological maturation of the newborn. Premature newborns with very low birth weight (VLBW<1,500 g) constitute a group with the highest risk of sensorineural hearing loss. Our objective was to ascertain the degree of hearing loss, sensorineural hearing loss and presence of the association to other risk factors for hearing loss in VLBW infants included in the Universal Hearing Loss Screening Programme at the University Mother-Child Hospital of Gran Canaria (Spain) in the 2007-2010 period.

MATERIAL AND METHODS

This was a retrospective study of 364 infants with VLBW, measured by transient evoked otoacoustic emissions and auditory brainstem response.

RESULTS

There were 112 newborn (30.8%) referred for auditory brainstem response. A diagnosis of hearing loss was given to 22 newborns (2.2%), 14 had conductive hearing loss and 8, sensorineural hearing loss (SNHL), of which 2 had bilateral profound hearing loss. The VLBW newborn presented the association to another risk factor in more than a quarter of the sample studied. All those diagnosed with SNHL were premature.

CONCLUSIONS

The percentage of VLBW newborns diagnosed with hearing loss is higher than expected in the general population. All those diagnosed with SNHL were premature and presented one or 2 hearing risk factors associated with VLBW.

[Universal newborn hearing screening in Cantabria (Spain): results of the first two years]

AIMS

We present the results of the first 2 years of universal newborn hearing screening in Cantabria.

MATERIAL AND METHODS

We performed a descriptive study of screening with two levels of transient evoked otoacoustic emissions in 8,836 newborns, diagnostic confirmation with auditory brainstem response, and treatment.

RESULTS

The coverage of the first two levels of otoacoustic emissions was 98.4 % and 99.5 %. The incidence of risk factors was 3.08 %. A total of 6.7 % of those studied in the first stage were referred to the second, and 0.7 % of those studied in the second stage were referred to testing of auditory brainstem responses. Of the patents referred to the second stage, 97.6 % attended, and of those referred to the third stage 87.1 % attended. The positive predictive value after the second session of otoemissions was 7.9 %, and the false positive rate was 3.3 %. Sensorineural and bilateral hearing loss was diagnosed in 11 children, and permanent unilateral hypoacousia was diagnosed in one child, representing an incidence of 1.38/1,000 newborns. Sixty percent were diagnosed before the age of 3 months and 100 % before the age of 7 months. Fifty percent began treatment before the age of 6 months and 90 % before the age of 1 year. Of three cochlear implants indicated, two were implanted at 11 and 13 months. The cost was 1.3 3 per child screened and 867 3 for each case diagnosed.

CONCLUSIONS

All the objectives of the first and second stages of screening were achieved. The continuity index anticipated for the third stage (87.1 vs 95 %) and access to treatment at 6 months (50 % vs 100 %) were less satisfactory, although these results compare favorably with those of previously published studies.

[Program of hearing loss early detection in newborn infants in Cantabria. Results of the first year of activities]

AIMS

To report the findings in the first year of follow-up of the Cantabrian Program to screen newborn babies for congenital permanent hearing loss.

METHODS

The study population consisted of infants born during a year period in Cantabria (Spain). Universal hearing screening by transient evoked otoacoustic emissions (TEOAE) in 2 stage protocol was performed. Infants with failure scores in these 2 stages and those with risk factors for hearing loss were referred for diagnostic evaluation with auditory brainstem response. Hearing aids were recommended for those infants who had bilateral hearing loss and referrals to infant speech and language rehabilitation.

RESULTS

Out of the 4117 eligible babies, 3987 were studied. One hundred and ten (2.6) had risk factors for hearing loss, 3.5% were referred for audiological assessment and 1.2/1000 were diagnosed as having a permanent hearing loss. The false-positive rate was 0.72% after the two-stage screening procedure was performed. Positive predictive value for permanent hearing loss was 10%.

CONCLUSIONS

During the first year working with the Cantabrian Screening Program for congenital permanent hearing loss in newborn babies, the most part of the proposed aims have been achieved.

[Results of one year's application of a universal protocol for the early detection of hearing loss in neonates]

These are the results of the first year of the application of a universal programme for the early detection of neonatal deafness. Our objective is making a diagnosis of all the unilateral or bilateral cases of hearing loss above 35 dB HL, before the age of 6 months. The detection strategy has 2 screening phases with transient evoked otoacoustic emissions (TEOAE) and one diagnostic phase with auditory brain stem response (ABR). The ABR were carried out both on those patients that failed the TEOAE screening and on the neonates with hearing loss risk factors. Of the 1,277 living newborn babies (NB), we evaluated 94%. 3.3% of the NB showed hearing loss risk factors. 90% of the NB passed the first TEOAE in both ears and, after the second TEOAE, only 2.5% of the NB reached the diagnostic phase. We provided early detection and treatment of 0.58% of cases of bilateral severe-deep hearing loss. Finally, the results obtained are examined together with the importance of planning universal hearing screening.