Age Intervention Research Articles

Treatment of undescended testicles—how, when and where?

The optimal mode of treatment of undescended testes and the optimal age for intervention has been discussed for decades, without reaching a worldwide consensus. Numerous publications report on the anatomical outcome of various treatment modalities, where ‘success’ is defined as a testis in the scrotum, without obvious atrophy. The real goal of treatment, to achieve normal or at least improved spermatogenesis in the undescended testis, has not attracted the same number of clinical scientists. The reason is obvious – treatment is carried out in childhood, while the final outcome as to testicular function has to await full pubertal development, many years later. Prospective, randomised and controlled studies, from childhood to adulthood, comparing different modes of treatment and different ages for intervention would be required to reach final conclusions. Such studies have so far not been published. However, cryptorchidism is the most common abnormality of newborn boys, with an incidence at birth of 3–9%, decreasing to 1–2% of all boys at 3–6 months of age. Therefore, clinical guidelines are needed, even if the final conclusions from long-term prospective studies are lacking. Therapeutic traditions have governed the management of undescended testes more than scientific facts. This is probably the reason why both the mode and the timing of treatment show strong local variance. Thus, in many parts of Europe, hormonal treatment at 2–4 years of age is recommended, while surgery at an early age is preferred in North America. This strategy of early treatment is based on histopathological observations of decreased number of spermatogonia in seminiferous tubules in undescended testes from age 2 years and on. However, hard evidence for better spermatogenesis achieved by very early surgery has been scarce. Over the past few years, evidence has accumulated that hormonal therapy (mostly through injection of human chorionic gonadotropin, hCG) is not very effective (as measured by a scrotal position after treatment), and may even damage future spermatogenesis through increased apoptosis. Emerging evidence also suggests that surgery before one year of age results in better postoperative testicular growth than orchiopexy at age 3 years. These findings and others prompted a meeting of Nordic experts in the fields of paediatric endocrinology, urology, pathology and anaesthesiology as well as testicular physiology. Consensus on treatment was reached, based on present knowledge: Surgery is preferred to hormonal therapy, and surgery should be carried out before 1 year of age. Since surgery at that age requires specially trained paediatric urologists/surgeons and anaesthesiologists, it should only be performed in centres with such facilities. The reasons behind the recommendations are presented in this issue of Acta Paediatrica as one common consensus statement by all participants, joined by five reviews on different aspects on the treatment of undescended testicles. I am convinced that both practicing paediatricians and specialized experts in the field will find these articles very interesting. We are very grateful that one of the front clinical scientists in the area, Professor John Hutson, from the Royal Children’s Hospital in Melbourne, has written a commentary to this series of papers.

The Ages of Intervention in Regions With and Without Universal Newborn Hearing Screening and Prevalence of Childhood Hearing Impairment in Australia

This article aims to (1) examine the impact of newborn hearing screening on age of hearing aid fitting, and (2) estimate the prevalence of permanent childhood hearing impairment and its profile across age and degree of impairment in Australia. The data were drawn from the Australian Hearing national database on all aided children under 21 years of age as at December 2006. The results indicated that children who were screened and diagnosed soon after birth were fitted by a median age of 3.4 months in New South Wales. The prevalence of moderate and more severe hearing loss (threefrequency average in the better ear of ≥ 40 dB HL) rises from 1.04/1000 live births at 3 years of age to 1.57/1000 live births for children between 9 and 16 years of age. The prevalence of mild degrees of hearing loss (threefrequency average in the better ear < 40 dB HL) rises from 0.28/1000 live births at 3 years of age to 1.68/1000 live births at 9 years of age and older. The findings show that early detection leads to early amplification. The change in prevalence with age implies that newborn hearing screening needs to be supplemented by hearing screening at later ages of early childhood so that timely amplification can be provided.

Effectiveness of Population-Based Newborn Hearing Screening in England: Ages of Interventions and Profile of Cases

The objective of this study was to determine the effectiveness in routine practice of the first phase of a national population-based newborn hearing screening and follow-up program that seeks to identify infants with bilateral permanent hearing loss of > or =40-dB hearing loss. The study was a part of the independent evaluation of the 23 first phase sites (annual birth population approximately 120,000) of the national newborn hearing screening program in England. For each infant identified with the defined hearing loss, the measures of interest were degree and type of hearing loss, presence of risk factors, age of first audiologic assessment, age of identification of hearing loss, age of enrollment in an early support program, and age of hearing aid fitting. Data collection took place over the first 2 years of the program. Data were provided on 169 infants with permanent bilateral moderate or greater hearing loss identified through screening 169487 infants. Fifty-four percent of all cases were from an "at-risk" population. Three fourths of these "at-risk" infants spent > or =48 hours in the NICU. For the whole sample, the median age at first audiologic assessment was 5 weeks; the median age of identification of the hearing loss and of enrollment in early support program was 10 weeks irrespective of the degree of hearing loss; and the median age at hearing aid fitting was 16 weeks. Infants with moderate hearing loss were fitted with hearing aids significantly later than those with severe and profound hearing loss. Properly implemented, a newborn hearing screening program based on whole populations and routine service provision can deliver satisfactory outcomes in terms of age of referral, identification, and intervention. The distribution of degree and type of hearing loss and proportion with risk factors was similar to that expected. The numbers identified were such as to suggest that very few cases were missed by the screening program.

Syntactic Movement in Orally Trained Children With Hearing Impairment

This study explored the comprehension and production of sentences derived by syntactic movement, in orally trained school-age Hebrew-speaking children with moderate to profound hearing impairment, aged 7;8-9;9 years. Experiments 1 and 2 tested the comprehension of relative clauses and topicalization sentences (with word orders of OVS [object, verb, subject] and OSV [object, subject, verb]) using a sentence-picture matching task. Experiments 3 and 4 tested the production of relative clauses using two elicitation tasks. Experiment 5 tested the comprehension of relative clauses with and without resumptive pronouns. As a group, the children with hearing loss failed to understand object relatives and OVS topicalization sentences. In the production tasks they either avoided producing a sentence with syntactic movement, by using a relative clauses with a resumptive pronoun instead of a gap or by producing a sentence without a relative clause, or produced ungrammatical sentences. They understood correctly object relatives with resumptive pronouns, which are not derived by movement. Both comprehension and production of the hearing-impaired group was significantly different from that of the hearing control group. Individual performance was strongly correlated with the age of intervention: only children who received hearing aids before the age of 8 months performed well in the comprehension tasks. Type of hearing aid, duration of use of a cochlear implant, and degree of hearing loss did not correlate with syntactic comprehension.

Evaluation of the Austrian Newborn Hearing Screening Program

Universal Neonatal Hearing Screening (UNHS) has been gradually implemented since the mid-nineties in Austrian maternity wards and neonatal intensive care units. This study evaluated the effect of UNHS on reducing age at identification as well as age of intervention for children with congenital and perinatal sensorineural hearing impairment. This was a retrospective analysis of clinical data of 394 Austrian children diagnosed with an at least mild degree (> 20 dB hearing level) of permanent sensorineural hearing loss. Age at identification and age at intervention were compared between children who underwent UNHS ('with UNHS') and those who did not undergo UNHS ('without UNHS'). The median of age of identification was 37.6 months in children without UNHS, and 3.9 months in children with UNHS. By six months of age, 69% of hearing-impaired children who underwent UNHS, were identified but only 6% of those without UNHS. At one year, the corresponding percentages are 80% and 12%, respectively. In children without UNHS, the degree of hearing loss was the most predictive factor of age at identification (median of age at diagnosis for profound hearing loss: 15 months; severe: 26 months; moderate: 52 months; mild: 73 months). In children with UNHS, age of identification was unrelated to degree of hearing loss (medians between 3.7 and 4.4 months). In the majority of children intervention began within one month after diagnosis, regardless of whether or not the child was identified by UNHS. UNHS greatly increases the proportion of children whose hearing impairment is diagnosed before six months of age. However, in some 20% of children, hearing impairment was diagnosed later than one year of age, despite having failed the screening. Additionally, data from this study suggest that about 15% of childhood hearing losses manifest themselves after the hearing screening period. Efforts are thus required for the early detection of these children as well.

Trade-offs between seedling growth, thinning and stand stability in Sitka spruce stands: a modelling analysis

The forest industry is increasingly adopting alternative silvicultural systems, involving regeneration beneath an existing forest canopy, rather than clear-felling and replanting. To apply these silvicultural systems in windy regions such as Britain and Ireland, it is essential that the interactions between thinning intensity, stand stability and seedling growth are properly understood. Here, we present a modelling analysis of the three key relationships between: (i) stand density and the proportion of incident radiation transmitted through a forest canopy as a stand is thinned; (ii) transmitted radiation and seedling growth, and (iii) stand density and stand stability. These relationships were examined using separate models of radiative transfer (MAESTRO), seedling growth, and stand stability/wind risk (ForestGALES). Output from the three models was synthesised to calculate whether a given stand thinned to a pre-defined stability limit would allow sufficient light to penetrate the canopy for seedling growth. A minimum transmittance of 20% was identified as a requirement for seedling growth, which corresponds to removing 45% of stand basal area. A thinning of this intensity left some stands susceptible to unacceptable wind damage, especially in old or previously thinned stands on soils where rooting is impeded. The results emphasised the fact that rooting conditions, thinning history and age of intervention are major constraints on the silvicultural options. In general, older stands are not suitable for conversion to continuous cover forestry (CCF) systems, and the transformation process should begin at pole stage, when heavy thinning does not leave the stand unstable. The analysis approach used here illustrates the potential for combining models to address complex forest management issues.

Observations on the use of the avian chorioallantoic membrane (CAM) model in investigations into angiogenesis.

The chorioallantoic membrane (CAM) is widely used as a model to examine angiogenesis, and anti-angiogenesis. Its advantages over mammalian systems include low cost, and ease of preparation, as well as the absence of a mature immune system. Although the use of this model presents a major opportunity to compare data generated in different laboratories, thereby expediting the evaluation of new drugs, angiogenic potential of cells and tissues, and body fluids, as well as to provide meaningful information concerning the molecular mechanisms involved, the wide range of methodologies used, especially in the quantification of the response, make any comparison essentially invalid. In this review, the major methodologies for all aspects of the use of the CAM in angiogenesis-related studies have been described. These include the source of the CAM, the methods for culture, and methods for evaluation of normal growth and of the response to an intervention. Methods for applying an intervention, the age for intervention and the duration of an intervention are documented. The structure and growth characteristics, the nature of possible responses to stimulation and inhibition of angiogenesis, and the complications of non-specific reactions have been examined. The need for a standardized approach to the use of the CAM model is obvious. One set of possible parameters is suggested.

Early intervention after universal neonatal hearing screening: impact on outcomes.

This article summarizes the developmental outcomes of Colorado children with significant hearing loss. Some of the research compares children born in hospitals that have implemented universal newborn hearing screening programs for newborns. Other research compares the developmental outcomes of children who have been early-identified with hearing loss. Early-identification is defined as identification of hearing loss within the first six months of life. Late identification in the Colorado studies is defined as age of identification of hearing loss after the age of six months. In a few of the Colorado studies, age at initiation of intervention was used. Within the Colorado system, age of identification can be interpreted as almost synonymous with age of intervention, as the vast majority of children enter intervention services with two months after the identification of the hearing loss. Children who were early-identified and had early initiation of intervention services (within the first year of life) had significantly better vocabulary, general language abilities, speech intelligibility and phoneme repertoires, syntax as measured by mean length of utterance, social-emotional development, parental bonding, and parental grief resolution. Two other studies (Nebraska and Washington state) of early- versus later-initiation of intervention services report findings similar to the Colorado studies. Direct comparisons with the historical literature are not possible because the developmental delays of what would now be termed "later-identified" were too low to report developmental ages for the birth through five-year-old population.

La rééducation en orthopédie dento-faciale. Point de vue d'un orthodontiste

In dentofacial orthopedics, rehabilitation concerns the performance of the orofacial functions. Orthodontists will therefore speak of rehabilitation of functions, or functional therapy. Orofacial functions seem to obey a hierarchical system in accordance with their physiological importance; the impact of their disorders on both muscular behavior and facial morphogenesis, proportionally to their physiological importance. Therefore, priority will be given at a very early stage to the rehabilitation of respiration: restoring nasal ventilation is indeed an essential condition to obtain balanced oral functions because oral ventilation conditions both muscular posture and the performance of other functions. A little later, affective immaturity symptoms closely linked to various persisting bad suction habits will be looked after. At last, the rehabilitation of phonation and chewing both affected by the previous dysfunctions will participate in acquiring correct lingual position. The age for intervention will before all depend on the dysfunctional etiopathogeny. The morphological context, the importance of the malocclusion, and some orthodontic appliances also play a role in the the dysfunctional requests and the alterations of oral behavior.

The effects of hearing loss and age of intervention on some language metrics in young hearing-impaired children : Ramkalawan T.W.; Davis A.C.BR. J. AUDIOL. (1992) 26/2 (97–107)

The effects of hearing loss and age of intervention on some language metrics in young hearing-impaired children : Ramkalawan T.W.; Davis A.C.BR. J. AUDIOL. (1992) 26/2 (97–107)

The effects of hearing loss and age of intervention on some language metrics in young hearing-impaired children : Ramkalawan T.W.; Davis A.C.Br.J. Audiol. (1992) 26/2 (97–107)

The effects of hearing loss and age of intervention on some language metrics in young hearing-impaired children : Ramkalawan T.W.; Davis A.C.Br.J. Audiol. (1992) 26/2 (97–107)

The effects of hearing loss and age of intervention on some language metrics in young hearing-impaired children.

This study examined the oral language production abilities of a group of young children with bilateral sensorineural hearing impairments (greater than 25 dB HL). The effects of age of intervention-as indexed by age of detection, referral, first appointment and hearing-aid fitting-and of the severity of their hearing impairments on spoken language and communication were the foci of the study. Children were aged between 27 and 80 months with hearing threshold levels ranging from 32 to 98 dB in the better ear. All were audio- and video-taped in their own homes, in an unstructured play setting with the mother. Measures of expressive language ability were extracted including mean length of utterance, vocabulary size, words per min., total utterance attempts per min., proportion of non-verbal utterances and the proportion of questions asked by the child. No significant correlations were found between the children's hearing impairments and their scores on the language measures once age at interview had been statistically controlled. However, significant correlations were found between the language measures and the ages at which the children received intervention for their hearing impairments, in particular for vocabulary and those language measures denoting the rate and quality of the child's interaction during the episode recorded. This finding is consistent with some of the arguments to be found in the small body of data addressing the question of early intervention.

Effects of early intervention on hearing impaired children.

A longitudinal study was conducted of 118 children with severe and profound hearing losses-Children were first tested when they were between 3 and 5 years and again in 3 or 4 years, using measures of receptive and expressive spoken language, receptive language in the child's primary educational modality, receptive and expressive mother-child communication, and social development. A multivariate design was used to investigate the effects of age of intervention, program intensity, and parent instruction on the children's linguistic and social development. Early intervention was associated with higher receptive language scores in the first, but not in the final year. Age of intervention was not related to any other language measure or the measure of social development. Consistent effects were not associated with program intensity or parent instruction.