Six year effectiveness of a population based two tier infant hearing screening programme.

AIMS: To determine whether a two tier universal infant hearing screening programme (population based risk factor ascertainment and universal distraction testing) lowered median age of diagnosis of bilateral congenital hearing impairment (CHI) >40 dB HL in Victoria, Australia. METHODS: Comparison of whole population birth cohorts pre and post introduction of the Victorian Infant Hearing Screening Program (VIHSP). All babies surviving the neonatal period born in Victoria in 1989 (pre-VIHSP) and 1993 (post-VIHSP) were studied. (1) Pre-1992: distraction test at 7-9 months. (2) Post-1992: infants with risk factors for CHI referred for auditory brain stem evoked response (ABR) assessment; all others screened by modified distraction test at 7-9 months. RESULTS: Of the 1989 cohort (n = 63 454), 1.65/1000 were fitted with hearing aids for CHI by end 1995, compared with 2.09/1000 of the 1993 cohort (n = 64 116) by end 1999. Of these, 79 cases from the 1989 cohort (1.24/1000) and 72 cases from the 1993 cohort (1.12/1000) had CHI >40 dB HL. Median age at diagnosis of CHI >40 dB HL for the 1989 birth cohort was 20.3 months, and for the 1993 cohort was 14.2 months. Median age at diagnosis fell significantly for severe CHI but not for moderate or profound CHI. Significantly more babies with CHI >40 dB HL were diagnosed by 6 months of age in 1993 than in 1989 (21.7% v 6.3%). Compared to the six years pre-VIHSP, numbers aided by six months were consistently higher in the six years post-VIHSP (1.05 per 100 000 births versus 13.4 per 100 000 births per year). CONCLUSIONS: VIHSP resulted in very early diagnosis for more infants and lowered median age of diagnosis of severe CHI. However, overall results were disappointing.     

The distraction test: The last word?

Objective: Universal Newborn Hearing Screening (UNHS) programmes have been widely implemented, but their costs, benefits and long-term logistics remain to be clearly defined. There are few rigorous evaluations of alternative strategies. In this paper, we evaluate the performance of the distraction test component of the two-tiered Victorian Infant Hearing Screening Program (VIHSP). Methods: All babies born in the State of Victoria, Australia in 1993 who survived the neonatal period were screened for the presence of risk factors for hearing loss. Those at-risk were referred for Auditory Brainstem Evoked Response (ABR) screening by a professional audiologist. All others were screened by modified distraction test at age 7-9 months. This birth cohort was followed through age 6 for diagnoses of congenital hearing loss resulting in fitting of hearing aids. Estimates of false-positives, false-negatives, sensitivity, specificity and positive predictive values were determined for the distraction test as a population screen. Ages at diagnosis and aid fitting for screen failures with hearing loss were compared with current goals. Results: For targeted (moderate or greater-aided) losses, the distraction test yielded eight (0.02%) documented false-negatives (one severe and seven moderate) and an estimated 4265 (99%) false-positives. Distraction test sensitivity was 65%, specificity 91% and PPV 0.3%. Mean age at diagnosis for distraction test failures across all severities, including mild losses, was 23 (SD 18) months with a mean age at aid fitting of 26 (SD 20) months. Conclusions: The distraction test screen generated large numbers of false-positives and a significant number of false-negatives, performing particularly poorly with moderate losses. Ages at diagnosis and aid fitting for screen failures were far older than currently accepted goals. There is little evidence that the distraction test can be made to work acceptably as a population-based screen.     

Outcomes of neonatal screening for hearing loss by otoacoustic emission.

AIM: To assess universal neonatal screening for bilateral hearing impairments averaging 40 dBHL or worse in the better ear, using transient evoked otoacoustic emission screening (TEOAE) testing. METHODS: A three year cohort (14,353 infants born from January 1992 to 1995) was screened and subsequently followed up by hearing surveillance methods, including a distraction test screen from 7 months of age. The entire cohort was used to evaluate the outcome of the screen. A subcohort of 8172 district residents was used to evaluate the continuing worth of the distraction test programme. RESULTS: Nineteen infants (1.3/1000) with a targeted hearing impairment failed the neonatal TEOAE test. Six profoundly deaf infants identified by the TEOAE screen, were fitted with hearing aids at a median age of 16 weeks. One remained without an aid. Of 12 infants with a moderate impairment, only seven accepted hearing aid fitting and the median age of being fitted with an aid increased to 42 weeks. By the time of the analysis 22 children with a targeted hearing impairment (1.5/1000) had been identified from the cohort. Of the three missed neonatally, one was cared for elsewhere, another had a progressive loss, and the third had central deafness. Twenty children were ascertained with a congenital peripheral deafness. Of these, eight (40%) had risk factors identifiable neonatally. Only the child with central deafness was missed by TEOAE screening and subsequently identified by behavioural tests in infancy. The TEOAE screen outperformed the distraction test in terms of processes and yield and was 25% less expensive. CONCLUSIONS: The analysis confirmed the worth within the district of the TEOAE hearing screen. It will thus be continued as a universal neonatal screen with the distraction test being retained as a selective screen in the latter half of infancy.     

Late diagnosis of congenital sensorineural hearing impairment: why are detection methods failing?

This study was designed to look in detail at the paths to diagnosis for a group of 197 children with congenital sensorineural hearing impairment (SNHI), who were diagnosed between 1989 and 1991 in the state of Victoria, Australia. Despite the existence of universal infant screening at 7-9 months by distraction test or questionnaire, the median age at diagnosis for the study group was 18.0 months, with median age at aid fitting of 20.8 months, and median age at commencement of specialised intervention programmes of 22.3 months. Parent questionnaires completed for 143 (73%) of these children showed that 49% had known risk factors for hearing loss yet only 20% of them had been referred for audiological assessment before the 7-9 month screen. Only 63% of those eligible for the 7-9 month screen had received it. Of those children who were screened by distraction test 46% passed as did 57% of those screened by questionnaire. Twenty four parents (17%) described how they had initially 'denied' their own observations of their infants' abnormal hearing behaviour. When concerns were raised with professionals, 10% of parents were falsely reassured without audiological assessment. Detection methods are failing through a combination of poor screen test efficacy, incomplete population coverage, and parental and professional denial.     

Hearing screening practices among a national sample of primary care pediatricians

The objective of this study was to describe variations in hearing screening using a survey mailed to a national sample of primary care pediatricians prior to the 2003 American Academy of Pediatrics (AAP) hearing screening guidelines. Of the 390 primary care respondents, only 303 (78%) performed audiometry, routinely beginning at age 3 (32%), 4 (44%), or 5 (17%); 81% defined abnormal audiometry primarily as failure to hear at a specified decibel level: 15 dB hearing level (HL) (<1%), 16 to 20 dB HL (10%), 21 to 25 dB HL (23%), 26 to 30 dB HL (44%), 31 to 40 dB HL (16%), and more than 40 dB HL (6%). This study serves as a baseline for comparison with postguideline practices.     

Six month impact of false positives in an Australian infant hearing screening programme

Aims: To assess short and longer term parent reported impacts of false positive referrals in the Victorian Infant Hearing Screening Program (VIHSP). Methods: Mailed retrospective case-control survey of infants consecutively referred to VIHSP between December 1998 and April 1999 for whom audiology did not confirm permanent hearing loss, comprising 137 infants screened with a neonatal risk factor questionnaire and 148 older infants screened with two consecutive behavioural (distraction) tests. The two control groups comprised non-referred screened infants matched by domicile, age, and gender. Main outcome measures were parent reported emotions experienced before and after child''s audiology test, parent estimated impact of hearing loss, the Child Vulnerability Scale, audiology assessment satisfaction questionnaire, and questions relating to their child''s hearing and language development. Results: Final sample: at risk cases (AR) 108 (79% response), at risk controls 64 (51%); distraction test cases (DT) 103 (70%), distraction test controls 53 (41%). Parents across all groups believed that hearing loss would have major effects on a child''s language (91–96%), schooling (81–91%), and employment opportunities (67–75%). Before audiology, 71% (AR) and 72% (DT) of case parents were anxious/worried, falling to 4% and 15% afterwards. After the test 82% (AR) and 79% (DT) reported relief, but 19% and 18% continued to feel worried. Ongoing concerns about hearing, language, development, and general health were comparable for AR cases compared to controls, and for DT cases compared to controls. Conclusions: Hearing screening tests are generally well received. Parents are realistic about the impact of childhood hearing loss and report a range of negative emotions when a false positive hearing screen requires referral. Although most are reassured by a normal test, a substantial number report continuing concern.     

Six month impact of false positives in an Australian infant hearing screening programme.

AIMS: To assess short and longer term parent reported impacts of false positive referrals in the Victorian Infant Hearing Screening Program (VIHSP). METHODS: Mailed retrospective case-control survey of infants consecutively referred to VIHSP between December 1998 and April 1999 for whom audiology did not confirm permanent hearing loss, comprising 137 infants screened with a neonatal risk factor questionnaire and 148 older infants screened with two consecutive behavioural (distraction) tests. The two control groups comprised non-referred screened infants matched by domicile, age, and gender. Main outcome measures were parent reported emotions experienced before and after child's audiology test, parent estimated impact of hearing loss, the Child Vulnerability Scale, audiology assessment satisfaction questionnaire, and questions relating to their child's hearing and language development. RESULTS: Final sample: at risk cases (AR) 108 (79% response), at risk controls 64 (51%); distraction test cases (DT) 103 (70%), distraction test controls 53 (41%). Parents across all groups believed that hearing loss would have major effects on a child's language (91-96%), schooling (81-91%), and employment opportunities (67-75%). Before audiology, 71% (AR) and 72% (DT) of case parents were anxious/worried, falling to 4% and 15% afterwards. After the test 82% (AR) and 79% (DT) reported relief, but 19% and 18% continued to feel worried. Ongoing concerns about hearing, language, development, and general health were comparable for AR cases compared to controls, and for DT cases compared to controls. CONCLUSIONS: Hearing screening tests are generally well received. Parents are realistic about the impact of childhood hearing loss and report a range of negative emotions when a false positive hearing screen requires referral. Although most are reassured by a normal test, a substantial number report continuing concern.     

Rezeptiver Wortschatzumfang bilateral schallempfindungsgestörter Kinder im Verlauf

Objective

The aim of this study was to assess receptive vocabulary development in children with aided residual hearing, but without major co-morbidities.

Patients and Methods

A total of 26 boys and 27 girls (t1: 2.0–7.4 years old) with bilateral sensorineural hearing loss (average at frequencies of 0.5, 1, 2, 4 kHz >21 dB in the better hearing ear) were recruited out of the 1994 implemented Göttinger Hör-Sprachregister (Gö HSR). The mean age at diagnosis was 51.4 months (SD 19.6; min. 14; max. 85), the mean hearing aiding age: 51.9 months (SD 19.6). The children had an average nonverbal intelligence in Raven’s Coloured Progressive Matrices and in CMMS respectively. The individual assessment of receptive vocabulary was carried out at three time points using standardized test measures. The raw test scores were converted to T-scores (M=50; SD=10; normed for hearing children). The first psychometric examination took place after the ascertainment of the hearing loss (t1). Two follow-ups (t2, t3) were performed at 6–9 month time intervals.

Results

No child with a hearing loss >61 dB HL obtained an age appropriate receptive vocabulary score. On average, the study group exhibited an age-delayed lexical performance at t1 (M=38.7; SD=14.7) which significantly improved over time reaching the lower norm level at t3 (M=44.7; SD=18.0; p<0.001). The number of children with below norm performance did not change (t1=53%, t3=47%). The mildly hearing impaired children (21–40 dB) exhibited an age adequate receptive test score at t1 (except for three children). These three children with delayed results scored normally by t3. The children with moderate hearing loss (41–70 dB) improved significantly (t1–t3; p<0.001). The mean vocabulary performance of severe, bilaterally impaired children (>70 dB HL) did not increase.

Conclusion

Even a hearing loss <40 dB may negatively affect receptive vocabulary development. Receptive vocabulary outcome was not highly variable.     

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.     

Universal hearing screening using transient otoacoustic emissions in a community health clinic

Since 1993, targeted screening of high risk Camden and Islington babies has been carried out in hospital using the transient otoacoustic emission (TEOAE) technique and auditory brainstem responses (ABR). Because targeted screening is difficult to implement, a community pilot study using TEOAE was started in 1995, covering 7% of the resident population. Although uptake has not been above 80%, client satisfaction has been high and numbers requiring more detailed tertiary assessment have been modest (0.5% of the population screened). A comparison was made between the cost of a universal neonatal screen using TEOAE and distraction testing at 7 months of age. The neonatal screen would be no more expensive to implement universally, even when equipment costs are included. A combination of a universal neonatal screen with distraction testing at 7 months for those not screened is likely to give 96% coverage of hearing screening in the first year of life.

     

Qualitative analysis of parents' experience with early detection of hearing loss.

AIMS: To determine key themes from parents' comments on paths to diagnosis and intervention for their children with hearing loss, following introduction of at-risk neonatal hearing screening and modification of distraction test screening for infants not at-risk. METHODS: Parents of children born in 1993 in Victoria, Australia, who were eligible for screening via the Victorian Infant Hearing Screening Program and who were subsequently diagnosed with a permanent congenital hearing loss and fitted with hearing aids prior to the year 2000 were asked to complete a semi-structured questionnaire shortly after aid fitting. Two researchers independently analysed parent comments using the constant comparative method. RESULTS: Parents of 82 children (61%) replied to the questionnaire. Themes analysis revealed a generally positive response to neonatal ABR screening, with a mixed response to the distraction test; powerful emotions experienced by parents at diagnosis including denial and shock; frustration arising from delays in diagnosis, and communication difficulties with providers. Special difficulties testing children with other medical and developmental problems, confusion about tympanostomy tube insertion, and difficulty with wearing hearing aids were also reported. Some children had experienced problems in the school setting. Experience of post-diagnostic services was generally positive. CONCLUSIONS: Parents need greater support both during the testing of screen failures and at the time of diagnosis. Providers need more training in how to communicate findings to parents, particularly at times when parents are experiencing strong emotions. Parents need more strategies to enable hearing aid wearing in very young children. Some children with additional medical, developmental, and behavioural problems need specialised approaches to testing.     

Universal neonatal hearing screening: the Siena (Italy) experience on 19,700 newborns

BACKGROUND: Hearing loss (HL) is likely to be the most common congenital abnormality in humans, with a reported prevalence of 1 to 3 per 1000 live births. Early detection and intervention is critical to prevent the adverse consequences of a delayed diagnosis on speech, language and cognitive development. As 33-50% of all congenital HLs cannot be detected in a selective hearing risk, use of universal neonatal hearing screening (UNHS) programs is expanding. AIMS: We tested the value of a UNHS protocol, based on a two-stage strategy of Transient Evoked Otoacoustic Emissions (TEOAEs) in all infants, followed by diagnostic auditory brainstem response (ABR) testing in those infants who did not meet TEOAE pass criteria and those infants at high risk for hearing loss. METHODS: TEOAES (292 DP Echoport OAE Analyzer) served as the initial screen, followed by diagnostic ABR (Amplaid MK12) in newborns that did not meet pass criteria for TEOAEs. Additionally, all infants at high audiologic risk according to the Joint Committee on Infant Hearing received a diagnostic ABR evaluation. Of 21,125 total live births, 19,700 were tested (April 1, 1998-July 31, 2006). Accuracy of the UNHS strategy in predicting congenital HL was evaluated by calculating sensitivity, specificity, positive predictive value and negative predictive value. RESULTS: Prevalence for all HLs in the neonatal period was 1.78/1000 l.b. (35/19,700), with bilateral HL in 1.42/1000 l.b. (28/19,700) [low risk rate: 0.43/1000 l.b. (8/18,356); high risk infants rate: 14.88/1000 l.b. (20/1344)]. All the HL infants were diagnosed <3 and received intervention <6 months age. ROC curves results showed 100% sensitivity (95% C.I.: 89.0-100) and 99.3% specificity (95% C.I.: 99.2-99.4) of the two-stage strategy in detecting congenital HLs [area under the ROC curve: 0.997 (95% C.I.: 0.995-0.997)]. CONCLUSIONS: (1) The epidemiology of congenital HLs widely justifies UNHS; (2) a two-stage TEOAE and diagnostic ABR screening for congenital HL is feasible, minimally invasive and accurate in the early detection of congenital HL; and (3) a congenital HL screening strategy based exclusively on the use of TEOAEs should always consider the possibility of false negative cases.     

Prevalence of Childhood Hearing Loss and Secular Trends: A Systematic Review and Meta-Analysis

BackgroundBetter epidemiologic information on childhood hearing loss would inform research priorities and efforts to prevent its progression.ObjectivesTo estimate prevalence and secular trends in children's hearing loss.Data SourcesWe searched MEDLINE and Embase from January 1996 to August 2017.Study Eligibility CriteriaWe included epidemiologic studies in English reporting hearing loss prevalence.Study Appraisal and Synthesis MethodsThe modified Leboeuf-Yde and Lauritsen tool was used to assess methodological quality. Meta-analyses combined study-specific estimates using random-effects models.ParticipantsChildren 0 to 18 years of age.ResultsAmong 88 eligible studies, 43.2% included audiometric measurement of speech frequencies. In meta-analyses, pooled prevalence estimates of slight or worse bilateral speech frequency losses >15 decibels hearing level (dB HL) were 13.1% (95% confidence interval [CI], 10.0–17.0). Using progressively more stringent cutpoints, pooled prevalence estimates were 8.1% (95% CI, 1.3–19.8) with >20 dB HL, 2.2% (95% CI, 1.4–3.0) with >25 dB HL, 1.8% (95% CI, 0.4–4.1) with >30 dB HL, and 0.9% (95% CI, 0.1–2.6) with >40 dB HL. Also, 8.9% (95% CI, 6.4–12.3) had likely sensorineural losses >15 dB HL in 1 or both ears, and 1.2% (95% CI, 0.5–2.1) had self-reported hearing loss. From 1990 to 2010, the prevalence of losses >15 dB HL in 1 or both ears rose substantially (all P for trend <.001).LimitationsThe studies had high heterogeneity and offered limited information for hearing loss types and secular trend.Conclusions and ImplicationsChildhood slight or worse hearing loss is prevalent and may be increasing. Advances in understanding hearing loss trajectories, causes, and prevention would require international repositories and longitudinal studies with audiometric data beginning in childhood.Systematic Review Registration NumberPROSPERO 2016 CRD42016034148.     

A national two year follow up study of extremely low birthweight infants born in 1996-1997

Objective: To study neurodevelopmental outcome in a two year cohort of extremely low birthweight (ELBW) infants at 18 months corrected age, to compare the development of the ELBW infant subcohort with that of control children, and to find risk factors associated with unfavourable outcome. Study design: All 211 surviving ELBW infants (birth weight < 1000 g) born in Finland in 1996–1997 were included in a national survey. The ELBW infants (n = 78) who were born and followed in Helsinki University Hospital belonged to a regional subcohort and were compared with a control group of 75 full term infants. A national follow up programme included neurological, speech, vision, and hearing assessments at 18 months of corrected age. Bayley infant scale assessment was performed on the subcohort and their controls at 24 months of age. Risk factors for unfavourable outcome were estimated using logistic and linear regression models. Results: The prevalence of cerebral palsy was 11%, of all motor impairments 24%, of ophthalmic abnormalities 23%, and of speech delay 42%. No impairment was found in 42% of children, and 18% were classified as severely impaired. The prevalence of ophthalmic abnormalities decreased with increasing birth weight and gestational age, but the prevalence of other impairments did not. In the subcohort, a positive correlation was found between the date of birth and Bayley scores. Conclusion: Ophthalmic abnormalities decreased with increasing birth weight and gestational age, but no other outcome differences were found between birthweight groups or in surviving ELBW infants born at 22–26 weeks gestation. The prognosis in the regional subcohort seemed to improve during the short study period, but this needs to be confirmed.     

Hearing loss in children with osteogenesis imperfecta

Osteogenesis imperfecta (OI) is a genetic disorder of connective tissue. Progressive hearing loss is one of the principal symptoms of OI, affecting about 50% of adult patients. Hearing loss may also occur in childhood and results in additional disability in education and psychosocial adaptation and aggravates the physical handicap. This can be avoided by appropriate otological and audiological treatment. In a nationwide search, 254 Finnish patients with OI were identified indicating a prevalence of 4.9/100 000. Of the 60 children, 45 aged between 4 and 16 years accepting to participate the study on hearing, were evaluated by a questionnaire and clinical audiometry. Hearing loss was defined as pure tone average (PTA_{0.5–2 kHz}) more than 20 dB hearing level (HL). A clinical geneticist determined the type of OI among the 45 patients. Two sporadic OI cases with conductive hearing loss were ascertained (4.4%): An 11-year-old girl with type IV OI with a PTA_{0.5–2 kHz} of 35/40 dB HL and a 15-year-old boy with type IV OI with a PTA_{0.5–2 kHz} of 27/18 dB HL. In addition, a 6-year-old girl with familial OI type I had either a congenital sensorineural deafness or early progressive deafness with PTA_{0.5–2 kHz} of 97/103 dB HL, probably of unrelated aetiology. Conclusion Hearing loss in children with osteogenesis imperfecta is less frequent than generally suspected. Nevertheless, it is recommended that audiometry is performed in children with osteogenesis imperfecta even without symptoms of hearing loss at the age of 10 years, and repeated every 3 years thereafter. Received: 13 October 1999 and in revised forms: 20 December 1999, 13 January 2000 and 24 January 2000 / Accepted: 25 January 2000     

Hearing impairment: a population study of age at diagnosis, severity, and language outcomes at 7-8 years

Background: Better language outcomes are reported for preschool children with hearing impairment (HI) diagnosed very early, irrespective of severity. However, population studies of older children are required to substantiate longer term benefits of early detection. Aims: To study impact of age of diagnosis and severity of HI in a population cohort of 7–8 year old children. Methods: Eighty eight 7–8 year old children born in Victoria, who were (a) fitted with hearing aids for congenital HI by 4.5 years and (b) did not have intellectual or major physical disability were studied. Main outcome measures were Clinical Evaluation of Language Fundamentals (CELF) and Peabody Picture Vocabulary Test (PPVT). Predictors were pure tone average (0.5, 1, 2 kHz) in better ear at diagnosis and age at diagnosis. Marginal (adjusted) means were estimated with general linear models. Results: Response rate was 67% (n = 89; 53 boys). Mean age at diagnosis was 21.6 months (SD 14.4); 21% had mild, 34% moderate, 21% severe, and 24% profound HI; mean non-verbal IQ was 104.6 (SD 16.7). Mean total CELF score was 76.7 (SD 21.4) and mean PPVT score 78.1 (SD 18.1). Age of diagnosis, adjusted for severity and IQ, did not contribute to language scores. In contrast, adjusted mean CELF and PPVT language scores fell sequentially with increasing severity of HI. Conclusions: More severe HI, but not later diagnosis, was strongly related to poorer language outcomes at 7–8 years. Further systematic study is needed to understand why children with hearing impairment have good or poor outcomes.     

Effects of cognitive, motor, and sensory disabilities on survival in cerebral palsy

Background: Cerebral palsy presents with a range of severity of cognitive, motor, and sensory disabilities, which might affect survival. Aims: To quantify the effects of motor, cognitive, and sensory disabilities, year of birth, birth weight, and gestational age on survival in cerebral palsy. Methods: A cohort of children with cerebral palsy born between 1966 and 1989 to mothers resident in a defined geographical region was subdivided into early impairment (EICP: cerebral insult prenatally or within 28 days of birth) or late impairment (LICP: insult at least 28 days after birth). Deaths are notified by the National Health Service Central Register. Birth and disability details were obtained from clinical records. Survival analyses were carried out. Results: Severe motor disability was associated with a 30 year survival of 42% and severe cognitive disability with a 30 year survival of 62%. Severe visual disability was associated with a 30 year survival of 38%, but the association of survival with hearing disability was weak. EICP had better survival than LICP but the difference was not significant after allowing for severity of functional disabilities. Normal birth weight infants (≥2500 g) showed no birth cohort effect, but the 10 year survival of low birth weight (<2500 g) infants declined from 97% for 1966 to 89% for 1989 births. Conclusions: Survival in cerebral palsy varies according to the severity and number of functional disabilities and by birth weight. Among low birth weight children, survival declined steadily from 1966 to 1989 after allowing for disability. The disabilities reported do not capture all the factors affecting survival of preterm infants.     

Neonatal hearing screening

Severe congenital hearing impairment is an important handicap affecting 0.1% of live-born infants and 1%–2% of graduates of Neonatal Intensive Care Units. The prognosis for intellectual, emotional, language and speech development in the hearing-impaired child is improved when the diagnosis is made early and intervention is begun before the age of 6 months. The usual age at diagnosis of hearing impairment is at least 18–30 months (or even later in cases of less severe hearing impairment) where there are no screening programmes. When screening is carried out using distraction methods at the age of approximately 9 months some hearing-impaired infants are missed and those discovered are at least 15–18 months before intervention begins. Neonatal screening could give hearing-impaired children the best chances for optimal care and development. Universal neonatal hearing screening is necessary, because, when neonatal hearing screening is restricted to high risk groups 30%–50% of infants with hearing loss are not discovered. The methods available for neonatal hearing screening are discussed in this paper.Conclusion In our view automated measurement of auditory brainstem responses is the most valuable method for universal neonatal hearing screening.     

AUDITORY BRAINSTEM RESPONSES (ABR) IN HIGH-RISK NEONATES

ABSTRACT. In the present study, auditory brainstem responses (ABR) were recorded in 60 highrisk neonates in the intensive care unit selected by the following criteria: Birth-weight <2000 g, hyperbilirubinemia requiring phototherapy or exchange transfusion, idiopathic respiratory distress syndrome, artificial ventilation, asphyxia, sepsis or meningitis, intracranial haemorrhage, neurological symptoms and potential ototoxic medication (aminoglycoides, furosemide). The infants tested ranged in gestational age from 27-44 weeks. The ABR testing was performed in a sound-proof room using the Madsen (ERA-74) equipment. Four infants did not reveal responses to 70 dB HL ("nonresponders"), and the total of 10 neonates (16.6%) had abnormal ABR-tests, when the physiological changes related to gestational age and conceptional age (gestational age plus the age after birth) were taken into account. The 10 neonates with abnormal tests were reexamined after discharge, and in six there were no improvement of threshold sensitivity. Three of the "nonresponders" were retested several times within the two years after birth (one died at age 18 months of pertussis), and none of them revealed ABR at stimulus intensity of 70 dB HL. They all attend an audiological training program started at age of six months as a consequence of the early diagnosis of impaired auditory function. It is our opinion that a routine ABR-evaluation should be performed on high risk neonates (criteria mentioned above) in the newborn intensive care unit. Retesting of infants with abnormal responses within three months, and several times within the next two years if abnormal responses persist, is important. Transient impairment of auditory functions is not uncommon in these infants. However, the children with persisting hearing impairment should be discovered early to attend an early audiological training program.     

Auditory profile in children recovering from bacterial meningitis

In the present study BERA profile of 30 post-meningitic children was compared with 15 normal children of the same age and it was observed that 36.6% children in the age range of 6 months to 36 months were found to have varying degree of sensorineural deafness. Severe bilateral sensorineural hearing loss (>80 dB) was observed in 6.6% children and moderate (40–80 dB) hearing loss in 30% of children. Abnormalities were bilateral in both the samples of children with severe hearing loss (>80 dB) whereas among 9 children who had moderate hearing loss abnormalities were bilateral in one patient and unilateral in the remaining 8 children. A relationship between higher incidence of sensorineural deafness and younger age of children, and occurence of seizures during meningitis were noted. But no relationship was observed with either sex, hydrocephalus, subdural effusion or with low CSF sugar and high CSF proteins.