Vestibulospinal component of postural control (vestibular function) in very preterm infants (25 to 27 weeks) at 3, 6, and 12 months corrected age

Postural control, which is important for the development of all movement, balance, and locomotion, depends a great deal on the vestibulospinal component of vestibular function in early childhood. Vestibulospinal input is important for muscle power regulation, which, in turn, influences postural control. The aim of this study was to focus particularly on this component of vestibular function during the first year of life in 67 infants with a very short gestational age (25-27 weeks), to search for possible neonatal confounders, and to see whether it influences the course of muscle power development in preterm infants. Outcome was described as being optimal, suspect, or abnormal. The infants were categorized into the Neonatal Medical Index according to the severity of neonatal illness and separately into three groups for neonatal brain ultrasonography findings (normal to severe abnormalities). At the age of 3 months, 20 infants performed optimally on all items testing vestibular function, increasing to 40 at 6 months and 48 at 12 months. This significant improvement (also seen in muscle power regulation) was primarily caused by better head control (during the traction response and prone position), whereas less shoulder retraction and hyperextension were found in the sitting position. Vestibular function was significantly related to brain ultrasonography classification but not to gestational age, birthweight, the Neonatal Medical Index, or gender.     

The role of birthweight discordance in the intellectual and motor outcome for triplets at early school age

Aim We assessed motor and intellectual outcome in triplets at school age and investigated the predictive value of perinatal and demographic factors. Methods Seventy‐one live‐born newborn infants (24 triplet pregnancies) were prospectively enrolled at birth. At the age of 6 years, 58 children (31 males, 27 females; mean gestational age 31.2wks [SD 2.2wks]; mean birthweight 1622g [SD 440g]) returned for a neurodevelopmental examination. A comparison group for triplets born before 32 gestational weeks comprising 26 gestational age‐, birthweight‐, and sex‐matched singletons was also recruited (mean gestational age 30.1wk [SD 1.5wk]; mean birthweight 1142g [SD 210g]; 12 males, 14 females). The Zurich Neuromotor Assessment was used to examine motor performance, and intellectual abilities were assessed with the Kaufman Assessment Battery for Children (K‐ABC). Results Motor performance and movement quality in these individuals was significantly reduced compared with the test norms for all motor tasks (p<0.001) other than static balance. The mean values on the Mental Processing Composite (95.3, SD 8.4) and the Achievement Scale (90.1, SD 13.8) of the K‐ABC were also lower than those in the test reference (p<0.05 and p<0.01 respectively). Triplets born at less than 32 weeks’ gestation showed poorer pure motor and adaptive gross motor performance (both p<0.05) than, but similar intellectual performance to, the gestational age‐, birthweight‐ and sex‐matched singletons. Poor outcome was predicted by low socio‐economic status and by intertriplet birthweight discordance (both p<0.01). Interpretation Triplets were at an increased risk of mild motor and intellectual impairments. This finding is important for tailoring therapeutic interventions for these children and for parental counselling. Very preterm triplets showed similar outcomes to the singleton comparison children, except that they had poorer motor performance. Low socio‐economic status was a major risk factor for impaired intellectual development. In addition, birthweight discordance may also be considered a predictor for poor long‐term motor and intellectual outcome in triplets.     

Neonatal microstructural development of the internal capsule on diffusion tensor imaging correlates with severity of gait and motor deficits

Neonatal microstructural development in the posterior limbs of the internal capsule (PLIC) was assessed using diffusion tensor imaging (DTI) fractional anisotropy (FA) in 24 very-low-birthweight preterm infants at 37 weeks' gestational age and compared with the children's gait and motor deficits at 4 years of age. There were 14 participants with normal neonatal FA values (seven females, seven males; born at 27.6 weeks [SD 2.3] gestational age; birthweight 1027g [SD 229]) and 10 participants with low FA values in the PLIC (four females, six males; born at 28.4 weeks [SD 2.0] gestational age; birthweight 1041g [SD 322]). Seven of the 10 children with low FA and none of the children with normal FA had been diagnosed with CP by the time of gait testing. Among children with low neonatal FA, there was a strong negative correlation between FA of the combined left and right side PLIC and log NI (r=-0.89, p=0.001) and between FA and GMFCS (r=-0.65, p=0.04) at 4 years of age. There was no correlation between FA and gait NI or GMFCS at 4 years of age among children with normal neonatal FA. This preliminary study suggests neonatal DTI may be an important predictor of the severity of future gait and motor deficits.     

Ventricular dilatation in relation to outcome at 2 years of age in very preterm infants: a prospective Finnish cohort study

Aim The aim of this study was to analyse the relation between ventricular dilatation at term and neurodevelopmental outcome at 2 years corrected age in infants of very low birthweight (VLBW) or very low gestational age (VLGA). Method A total of 225 VLBW or VLGA infants (121 males, 104 female; mean birthweight 1133g, SD 333g; mean gestational age 29wks, SD 2wks 5d) born in Turku University Hospital were included. Ventricular–brain ratio and the widths of each lateral ventricular horn were determined using ultrasonography, and the volume of the ventricles was measured by magnetic resonance imaging at term. The 2‐year outcome measures included scores for the Hammersmith Infant Neurological Examination, the presence of cerebral palsy (CP), the Mental Developmental Index (MDI) of the Bayley Scales of Infant Development (2nd edition), and the presence of severe hearing or vision impairments or any neurodevelopmental impairment (NDI). Results CP was diagnosed in 15 participants (6.7%) and severe hearing deficit in 12 participants (5.3%). No severe vision impairment was found. Mild and severe cognitive delay was found in 24 (10.7%) and 8 (3.6%) of the VLBW or VLGA infants respectively. Isolated ventricular dilatation did not increase the risk for developmental impairments. However, ventricular dilatation with additional brain pathology was significantly associated with CP, MDI score below 70, and NDI. A ventricular–brain ratio above 0.35 was a sensitive measure of developmental impairment. Interpretation Ventricular dilatation at term increases the risk of poor developmental outcome only when associated with other brain pathology. The ventricular–brain ratio is a useful clinical tool for determining the prognosis in VLBW and VLGA infants.     

Normative data and the effect of correction for prematurity on test scores in the psychomotor development of extremely low birthweight infants

This study was concerned with the problem how we should allow for gestational age at birth when evaluating psychomotor development in extremely low birthweight (ELBW) infants. The consequences of the use of corrected and uncorrected developmental test scores as to the degree of prematurity were studied in 27 consecutive ELBW children who had been categorized as being normal on neurological and psychological testing at 5 1/2 years. The present study provides evidence that the overall trend of psychomotor development in normal ELBW children is not accelerated, but is guided by maturation of the central nervous system. This study also suggests that there are no significant differences in the predictive value of corrected and uncorrected DQ scores after 2 years of age with respect to IQ scores at 5 1/2 years.     

Neonatal seizures in very preterm and very low birthweight infants: mortality and handicaps at two years of age in a nationwide cohort

In a nationwide, prospective survey on very preterm and/or very low birthweight infants (less than 32 weeks of gestational age and/or less than 1500 g birthweight) we studied the outcome at the corrected age of two years of children with neonatal seizures. Of the 1338 infants, originally enrolled in the study, 72 had neonatal seizures; of these 44 died and 11 developed a major handicap. Using a multivariate statistical method, a significantly increased risk of death as well as handicap was found in infants with seizures compared to infants without seizures. Nevertheless, 16 of the 28 survivors with neonatal seizures were considered normal at the corrected age of two years.     

Impaired motor performance and movement quality in very-low-birthweight children at 6 years of age

Motor performance and movement quality were quantitatively examined (Zurich Neuromotor Assessment: timed motor performances and associated movements) in 87 prospectively enrolled very-low-birthweight (VLBW; <1250g) children (38 males, 49 females; mean birthweight 1016.2g [SD 141.5]:, range 720-1240g; mean gestational age 28.7wks [SD 2], range 25.7-33.4wks) at 6 years of age. All motor tasks were below the reference population: pure motor (median z-score) -0.46; adaptive fine motor (pegboard) -0.99; adaptive gross motor -0.88; static balance -0.48; and associated movements -1.90. All tasks correlated with the degree of neurological abnormalities (p相似文献   

Phonological development in very‐low‐birthweight children: an exploratory study

Aim Very‐low‐birthweight (VLBW; birthweight <1500g and/or gestational age <32wks) children are at risk for speech problems. However, there are few studies on speech development in VLBW children at an early age. The aim of this study was to investigate phonological development in 2‐year‐old VLBW children. Method Twenty VLBW children without major neurosensory impairment (7 males, 13 females; mean birthweight 971g, SD 315; mean gestational age 28wks, SD 1.81) and 20 term children (7 males, 13 females; mean birthweight 3503g, SD 416; mean gestational age 40wks, SD 1.26) were compared on measures of phonological development derived from 20‐minute spontaneous speech samples of standardized mother–child play interaction as well as on standardized tests of cognitive and psychomotor development, language, and behaviour. Results VLBW children had significantly fewer acquired consonants (median 9, p=0.02) and a significantly lower phonological mean length of utterance (pMLU; median 4.1, p<0.01) than term children (median acquired consonants 10, median pMLU 5.0). Interpretation This study provides evidence for poor phonological development in even healthy VLBW children, compared with term‐matched children, independent of their cognitive, psychomotor, and language development, and their behavioural functioning.     

SIGNIFICANCE OF PRENATAL, PERINATAL AND POSTNATAL FACTORS IN THE DEVELOPMENT OF AGA PRETERM INFANTS AT FIVE TO SEVEN YEARS

The effects of prenatal, perinatal and postnatal events on developmental outcome at five to seven years of preterm infants with birthweights appropriate for gestational age were investigated in two separate cohorts: one a longitudinal study of 97 infants, the other a cross-sectional study of 249 infants. Among the prenatal variables, the number of minor congenital anomalies was negatively correlated with neurological development, as was the deformation score. The pregnancy optimality score was not significantly related to outcome. Among the perinatal variables, gestational age and birthweight had some significant correlations with development, but birth and neonatal optimality scores were only inconsistently significant in relation to outcome. Socio-economic status was strongly related to language and intellectual development. Infants with gestations of 32 to 36 weeks had a more favourable neurological and intellectual outcome than those born before 32 weeks: however, the former group comprised about 80 per cent of the population studied, so the majority of children with lower function were found in that group.     

Evaluation of the effect of thyroxine supplementation on behavioural outcome in very preterm infants

Two-hundred infants of <30 weeks gestational age were included in a randomized double-blind controlled trial to study the effect of thyroxine administration on neurodevelopmental outcome in very preterm children. The infants were given either a fixed dose of thyroxine (8 microg/kg birthweight/day) or placebo for the first 6 weeks of life. This paper evaluates the effect of thyroxine administration on behavioural outcome at the age of 2 years. More externalizing, especially destructive, behaviours were found in the group given thyroxine than in the placebo group. This difference was more pronounced in boys and in children born after 27 weeks' gestation. The thyroxine-treated children with behavioural problems had lower plasma-free thyroxine levels than the thyroxine-treated children without behavioural problems. This finding suggests that the presence of more behavioural problems in the group given thyroxine was not an immediate consequence of the treatment.     

TERM INFANTS WITH HYPOXIC-ISCHEMIC ENCEPHALOPATHY: OUTCOME AT 3.5 YEARS

A total of 167 term neonates with a diagnosis of hypoxic-ischemic encephalopathy (HIE) had detailed neurodevelopmental follow-up at 3.5 years of age. All 66 children with mild HIE were free from handicap; all seven with severe HIE were severely handicapped; and of the 94 with moderate HIE at birth, 21.3 per cent were handicapped. Mean IQ was significantly related to the category of HIE. Within the moderate HIE category, the neurological examination at discharge from the Neonatal Intensive Care Unit was more useful than the presence of neonatal convulsions in identifying children with subsequent developmental delay. Abnormalities on this examination related significantly to an increased number of handicapped children, decreased motor and language skills, and lower IQs. Although neonatal convulsions were associated with an increased number of handicapped children, they did not significantly affect most other developmental outcome measures. In term infants with documented HIE at birth, major neurodevelopmental dysfunction at 3.5 years depended more on prospectively established category of HIE than on other perinatal or social factors.     

Neurodevelopmental outcome in cystic periventricular leukomalacia (CPVL) (30 cases)

Thirty infant survivors had a wide spectrum of neonatal cystic periventricular leukomalacia (CPVL) diagnosed by ultrasound scans: 11 minor forms, 12 moderate forms, 7 major forms (categorized by both sagittal extent and coronal thickness). Eight cases were pure CPVL and 22 were associated with minor to moderate peri-intraventricular haemorrhage (PIVH), i.e. from (0-I) to (II-II). Mean gestational age: 31 +/- 2 weeks; mean birthweight: 1,532 +/- 356 g. The length of neurodevelopmental (ND) follow-up ranged from 13 months to 3 years and eight months. Of 11 children with minor CPVL, 9 were normal and two had moderate sequelae. Of 12 moderate CPVL, one was lost to follow-up, one had no motor disturbance but did have severe mental retardation (partial 7 p-), two were normal, one had a minor sequela, three had moderate and four had severe sequelae. Of the 7 major CPVL, one had moderate and 6 had severe sequelae. Cases including posterior lesions or presenting solely with such lesions had a worse outcome. In that range of PIVH, the outcome was related to the severity of CPVL and not to PIVH grade. All major late dilatations were associated with severe ND sequelae. Of 29 infants with early EEG tracings, the 7 children with early severe EEG abnormalities all had severe ND sequelae; 17 persistent EEG abnormalities, even mild, were associated with 9 severe and five moderate ND sequelae, and three normal outcomes. Combining US scans and EEG gives valuable prognostic information in minor and major CPVL, but less in the moderate forms.     

Neonatal neurological dysfunction in a cohort of very preterm and/or very low birthweight infants--relation to other perinatal factors and outcome at 2 years

Neonatal neurological dysfunction was found in only a small part of 1192 infants enrolled in an epidemiologic survey on very preterm (less than 32 weeks) and very low birthweight (less than 1500 gram) infants. A routine neurological examination was performed in the neonatal period by the attending paediatrician throughout all levels of care. The incidence of obvious neurological dysfunction was 8.1% and incidence of suspect neurological dysfunction was 6.1%. Multivariate analysis showed that gestational age, birthweight, low Apgar score, IRDS and, most of all, ICH were significantly associated with neonatal neurological dysfunction (N.D.). The mortality rate was very high in obvious and suspect ND infants (81.1% and 35.6% respectively) compared to neurologically normal infants (17.8%). This phenomenon was also found regarding the handicap rate at two years of age. Only 6% (n = 6) of the 96 infants with obvious ND survived without handicap. Using routine physical examination, a quarter of the very preterm or VLBW infants with later neurological disturbances were identified. A more standardized neurological examination, incorporated in the routine examination of newborns in all levels of care, might improve early identification of infants at risk for handicaps.     

Six-year follow-up of children with intrauterine growth retardation: long-term, prospective study

This prospective study was designed to characterize the neurodevelopmental and cognitive difficulties specific to children with intrauterine growth retardation and to detect early clinical predictors of these difficulties. Eighty-one children with intrauterine growth retardation were monitored up to 6 to 7 years of age using biometric parameters, perinatal risk questionnaires, and detailed neurodevelopmental and cognitive assessments. Forty-one children served as age-matched, appropriate for gestational age controls. A significant difference in growth parameters (P < .001), neurodevelopmental score (P < .05), and IQ (P < .05) was found between the children with intrauterine growth retardation and controls. A specific profile of difficulties in coordination, lateralization, spatial and graphomotor skills, and abundance of associated movements is typical of the children with intrauterine growth retardation and hints at possible later learning disabilities. The clinical parameters best predicting neurodevelopmental outcome were the neonatal risk score (P < .05) and the weight and height at 6 years of age (P < .05). The children with intrauterine growth retardation with neonatal complications had lower neurodevelopmental scores than the controls but no difference in IQ. Intrauterine growth retardation children diagnosed prenatally had the same neurodevelopmental and IQ scores as those diagnosed at birth, probably due to the careful perinatal and obstetric care provided. Children with intrauterine growth retardation demonstrate a specific profile of neurodevelopmental disabilities at preschool age. Early diagnosis and intervention could probably reduce these difficulties to a minimum.     

Ventricular Haemorrhages And Hypoxic-Ischaemic Lesions In Preterm Infants: Neurodevelopmental Outcome At 3 1/2 Years

The association of cerebral ultrasound images and developmental outcome at age 3 1/2 years was studied in 50 preterm infants (mean gestational age 31 weeks, mean birthweight 1450 g). 25 children had normal neonatal scans and 25 had abnormal neonatal scans; 11 without and 14 with ventricular dilatation. At one year a repeat scan was done and neurodevelopmental outcome was assessed. Follow-up results at 3 1/2 years stress the importance of long-term follow-up: at one year four of the 50 children had developmental deficits, at 3 1/2 years 13 had such deficits. At 3 1/2 years the risk of neurodevelopmental deficits was extremely high for children with persistent haemorrhagic and/or atrophic ventricular dilatation. There was significant over-representation of children with developmental deficits in the group with abnormal scans, both neonatally and at one year. The incidence of cerebral palsy was high in the group with large haemorrhages extending into the parenchyma and/or periventricular leucomalacia. In the group with periventricular leucomalacia there was also a greater risk of mental retardation with severe behavioural problems. Follow-up at a later age than 3 1/2 years will be necessary to determine the effects on the motor, intellectual and emotional development of these children.     

Prediction of cognitive abilities at the age of 5 years using developmental follow-up assessments at the age of 2 and 3 years in very preterm children

Aim This study investigated prediction of separate cognitive abilities at the age of 5 years by cognitive development at the ages of both 2 and 3 years, and the agreement between these measurements, in very preterm children. Methods Preterm children (n=102; 44 males; 58 females) with a gestational age less than 30 weeks and/or birthweight less than 1000g were assessed at the ages of 2 and 3 years using the second edition of the Bayley Scales of Infant Development, the Child Behaviour Checklist, and a neurological examination, and at the age of 5 years using the third edition of the Wechsler Preschool and Primary Scale of Intelligence. Results Cognitive development at ages 2 and 3 years explained 44% and 57% respectively of full‐scale intelligence at the age of 5 years. Adding psychomotor, neurological, and behavioural outcomes to the regression model could not or only marginally improve the prediction; adding perinatal and sociodemographic characteristics to the regression model increased the explained variance to 57% and 64% respectively. These percentages were comparable for verbal intelligence. Processing speed quotient and especially performance intelligence were predicted less accurately. Interpretation Not all aspects of intelligence are predicted sufficiently by the Mental Development Index at ages 2 and 3 years. Follow‐up of very preterm children until at least the age of 5 years is needed to distinguish between different aspects of cognitive development.     

Victimization: a newly recognized outcome of prematurity

Victimization by peers affects 10 to 20% of school children under the age of 12 years. Physical, verbal, and psychological victimization (being pushed, hit, called names, teased, being the target of rumours, theft, extortion) is associated with short- and long-term adjustment problems, such as peer rejection, social withdrawal, low self-esteem, anxiety, loneliness, and depression, as well as academic problems and school drop-out. Research on populations of school children (primary and secondary) has associated victimization with personal risk factors (the victim's characteristics and behaviour) and interpersonal risk factors (social relationships between peers). Studies on the social adjustment of preterm children at school age show that, even in the absence of a major motor or cognitive disability, this population has several personal risk factors associated with victimization. The objective of this study was to compare the level of victimization experienced by a group of 96 seven-year-old children born extremely preterm (EP, < 29 weeks of gestation; 49 females) against that experienced by a group of 63 term children (34 females) matched for age and sex, maternal level of education, and family socioeconomic status. The children born EP had a mean gestational age of 27.3 weeks (SD 1.2) and a mean birthweight of 1001.1g (SD 223) and normal birthweight children had a mean gestational age of 39.5 weeks (SD 1.5) and a mean birthweight of 3468.7g (SD 431). Physical and verbal victimization were assessed in a school setting by peers with individual sociometric interviews (Modified Peer Nomination Inventory). After controlling for physical growth (height and weight) at the age of 7 years, the data indicate two independent effects: males were more victimized than females, and children born preterm experienced more verbal victimization by their peers than their term classmates, even when participants with a visible motor, intellectual, or sensory disability were excluded. Several hypotheses are presented to account for the higher incidence of verbal victimization of preterm children.     

The developmental effects of an early intervention program for very low birthweight infants

We assessed the efficacy of an early intervention program (EIP) designed to promote the neonatal behavioral organization and developmental progress in infants born prematurely. The study subjects consisted of 48 very low birthweight infants (< or = 1,500 gms) who received care in NICU of Nagasaki University Hospital, Nagasaki, Japan. During 1993-1996, the experimental group (n = 30) received the NBAS (Neonatal Behavioral Assessment Scale) based intervention combined with a therapeutic program (EIP), for 44 weeks starting from 38 weeks of postmenstrual age. The control group (historical control, n = 18) received the standard medical-nursing care without EIP during 1990-1992. Developmental outcome was assessed in both groups using the NBAS examination after EIP at 44 weeks of postmenstrual age, and the Bayley Scales at 12 months corrected age. Multivariate analyses were performed to adjust for baseline variables that might be associated with the developmental outcome: sex, appropriate or light for dates infant, birthweight, gestational age, Apgar score at 1 minute, duration of intubation, and NBAS cluster score before EIP. In the NBAS examination after EIP, the experimental group achieved significantly higher scores in orientation, motor performance, state range and state regulation tasks than the control group. Furthermore, the experimental group showed significantly higher Bayley Mental and Psychomotor Developmental Indices compared with the control group. These results suggested that EIP was effective in promoting the neonatal neurobehavioral development of very low birthweight infants.     

Longitudinal study of neuropsychological outcome in blind extremely-low-birthweight children

This study evaluated neurological and psychological development in 10 blind children over a 4-year period. Five of the children were born preterm with an extremely low birthweight (ELBW) and a diagnosis of retinopathy, whereas the other five were term. All children received their first neurological examination at a mean age of 10 months and then annual follow ups. In addition, the Bielefeld Developmental Test for Blind Infants and Preschoolers (BDTB) was administered every 6 months (from the ages of 18 to 48 months) to assess developmental outcome in different domains (e.g. cognition, language, gross motor abilities). Results showed a higher number of peri- and neonatal complications in blind ELBW children as well as a significantly higher number of neurological symptoms over the 4-year period. At the mean age of 4 years 10 months, blind ELBW children had a significantly lower body weight, body height, head circumference, and body-mass index compared with the term children. Findings on psychological development revealed that blind ELBW children also had significantly lower scores on all domains covered by the BDTB. Finally, the overall score on the BDTB correlated significantly with gestational age, birthweight, duration of mechanical respiration, and days spent in hospital after delivery.     

Early postnatal doppler assessment of cerebral blood flow velocity in healthy preterm and term infants

The aim of the present study was to generate normal reference data for anterior and middle cerebral artery blood flow velocity and resistance index in preterm and term infants during the first 8 hours of life. The study population longitudinally included 120 healthy preterm and term infants (gestational age 24 to 41 weeks), all of appropriate weight for gestational age. The following parameters were studied: peak-systolic velocity, end-diastolic velocity, mean velocity, and resistance index. All parameters were measured in the anterior cerebral artery, in the left middle cerebral artery, and in the right middle cerebral artery with the use of Doppler colour ultrasonography. In addition, we studied the ratio of mean arterial blood pressure to mean velocity in the three cerebral arteries as a further estimate of cerebral relative vascular resistance. We found that cerebral blood flow velocities increased significantly with increasing gestational age and birthweight, both in the anterior cerebral artery and in the right and left middle cerebral arteries. Resistance index, both in the anterior cerebral artery and in the middle cerebral arteries, increased significantly only with increasing gestational age. Relative vascular resistance decreased significantly with increasing gestational age and birthweight in the three cerebral arteries. Significant differences were found (p<0.05) in these values between the anterior cerebral artery and the middle cerebral arteries. The narrow time frame (2 to 8 hours) that we used to evaluate cerebral blood flow velocity often represents a significant moment at which decisions are made that can be fundamental for the outcome of the newborn infant.