Spontaneous movements in the supine position of preterm infants with intellectual disability

Objective: Spontaneous movements at 2 months of corrected age in preterm infants with intellectual disability (ID) were investigated by assessing individual motor elements separated from movements involving the entire body. Methods: Video recordings of 20 preterm infants with ID (16 males, 4 females; median gestational age 26 weeks; median birth weight 810 g) were analyzed and were compared with those of 21 normal preterm infants (8 males, 13 females; median gestational age 30 weeks; median birth weight 1216 g). Results: In the preterm infants with ID at 2 months corrected age, startle response, lateral decumbent position, predominant shoulder rotation, and maintaining hip adduction were more frequently observed and hand sucking, maintaining shoulder abduction, to-and-fro shoulder abduction, to-and-fro elbow flexion, isolated hip adduction, to-and-fro hip abduction, and leg lift were less frequently seen than in the normal preterm infants (Fisher’s exact test, p < 0.05). Conclusion: Abnormal spontaneous movements at 2 months of age in preterm infants with ID result from persistent immature movements and non-emergence of mature movements.     

Physical condition of preterm infants with periventricular leukomalacia

The aim of this study is to determine the general condition of preterm infants with severe brain lesions and to compare it with that of normal preterm infants. The Score for Neonatal Acute Physiology (SNAP) was calculated in nine preterm infants with periventricular leukomalacia (PVL) whose initial electroencephalograms showed grade IV depression (PVL group), 18 preterm infants who did not require mechanical ventilation during the neonatal period, Spontaneous respiration (SR group), and 18 preterm infants who required mechanical ventilation (MV group). The sum of the following four items in SNAP was separately calculated and called the ‘lung score’: PaO₂, PaO₂/FiO₂ ratio, PaCO₂, and oxygenation index. In addition to SNAP, we evaluated some neonatal variables. SNAP is lower in the SR group than in the PVL (P<0.05) or MV (P<0.01) groups. The lung score was also lower in the SR group than in the PVL (P<0.05) or MV (P<0.01) groups. On the other hand, the residual score (SNAP minus lung score) was not significantly different among the three groups. The physical condition of infants with PVL was not poor, although respiratory distress was often observed.     

Spontaneous movements in the supine position of healthy term infants and preterm infants with or without periventricular leukomalacia

Aim: The individual motor elements presumed to be essential for motor development were determined from spontaneous movements involving the entire body of normal term and preterm infants. Then, diagnostic items for motor abnormality in infants with periventricular leukomalacia (PVL) were investigated. Methods: Video recordings of 24 healthy term infants, 21 normal preterm infants (8 males, 13 females; median gestational age 30 weeks; median birth weight 1216 g) and 14 preterm infants with PVL (6 males, 8 females; median gestational age 30 weeks; median birth weight 1360 g) were analyzed. Results: In healthy term infants, predominant shoulder rotation was noticed until 1 month of age. After 2 months of age, isolated movements of the shoulder, elbow, hip, knee, and ankle frequently emerged. In preterm infants with PVL at the corrected age of 2 months, startle response and predominant shoulder rotation were more frequently seen and isolated neck, shoulder, elbow, hip, knee, and ankle movements were less frequently seen than in the normal preterm infants (Fisher’s exact test, p < 0.025). Interpretation: At 2 months of age, isolated movements evolve, and their failure to occur is suggested to be a useful sign for the diagnosis of cerebral motor disorders.     

Ictal electroencephalographic findings of neonatal seizures in preterm infants

The aim of this study is to clarify the characteristics of ictal EEG findings of neonatal seizures in preterm infants. Seizures associated with ictal EEG changes were recognized in nine infants with gestational age of less than 37 weeks. Propagation, migration, shifting, changes in morphology of ictal EEG discharges were evaluated. Seizure manifestation was divided into the following categories; motor seizure, apneic seizure, automatic seizure and seizure without clinical symptoms. The types of the seizures were motor seizures in five infants, apneic in two, automatic in one and those without clinical symptoms in five. All seizures were of focal onset. The foci of seizures were temporal in six infants, occipital in two, central in one, and frontal in one. The morphology of ictal discharges was low voltage spikes or sharp waves in six infants, spikes in two, theta waves in one and high-voltage spiky theta in one. The propagation of ictal discharges was focal in five infants and regional in five. The migration of ictal discharges was observed in two infants and a shift in two. There was no clear relation between seizure manifestation and ictal EEG foci, duration of seizures and morphology or propagation of ictal discharges.     

Spontaneous movements of preterm infants is associated with outcome of gross motor development

Aims

We conducted a longitudinal cohort study to analyze the relationship between outcome of gross motor development in preterm infants and factors that might affect their development.

A nationwide survey of bilirubin encephalopathy in preterm infants in Japan

ObjectivesTo examine the clinical characteristics of bilirubin encephalopathy in preterm infants (pBE) in Japan.MethodsWe performed a two-step nationwide questionnaire survey. The initial survey determined the number of children with pBE. Using a structured questionnaire, the second survey clarified the clinical manifestations and characteristics of children with pBE, including the perinatal history, neonatal complications, neurological features, verbal communication, diet, and magnetic resonance imaging (MRI) and auditory brainstem response (ABR) findings.ResultsThe initial survey included 190 pBE infants, indicating an incidence of approximately 10 per year. Clinical information was available for 142 of them. The median gestational age was 26 weeks and the median birthweight was 883 g. As to neonatal complications, 20% had none, 25% had one complication, 54% had two or more. Head control was observed in 45% and functional gait in 8%. Purposeful hand use was seen in 41% of patients and verbal communication in 40%. MRI showed T2 hyperintensities in the globi pallidi in 111 of 136 patients, especially between 7 and 18 months of corrected age. ABR abnormalities were present in 88 of 117 patients.ConclusionspBE was infrequent but constantly observed during the study period, especially in very preterm infants, even in those with no severe neonatal complications. Severely impaired gross motor function and relatively preserved manual function and verbal communication were characteristic. MRI and ABR abnormalities will facilitate diagnosis.     

Re-evaluating preterm infants with the Bayley-III: Patterns and predictors of change

This study investigates the Third Edition of the Bayley Scales of Infant and Toddler Development (Bayley-III) and (1) mean difference scores, (2) test–retest correlation coefficients, (3) changes in rates of delay and classification from “delayed” to “not delayed,” and (4) infant birth, neonatal and sociodemographic predictors of change in scores from the first to second year of life among 131 preterm infants. Cognitive, Receptive Language and Fine Motor Subscale scores decrease and mean Gross Motor Subscale scores remain consistent from the first to second year of life. Bayley-III test–retest reliability ranged from small/fair to moderate from 8 to 20 months corrected age. Classification of delay is not stable over the first two years of life. One in 6 infants’ Language Index scores changed from a classification of not delayed at 8 months to delayed at 20 months. One in 10 infants’ Gross Motor Subscale scores changed from a classification of delayed at 8 months to not delayed at 20 months. Small for gestational age status predicts improved to nearly consistent Bayley Language Index and Receptive Subscale scores. Public insurance and history of sepsis predict decline in Bayley Language Index and Receptive Subscale scores from 8 to 20 months. Lower gestational age, race, and history of necrotizing enterocolitis and/or intestinal perforation also predict decline in Bayley Cognitive Index from 8 to 20 months. Predictors of decline in performance confirm known neonatal risk factors, are consistent with emerging evidence of detrimental immune related processes, and highlight the importance of inclusion of sociodemographic variables in understanding development in preterm infants.     

Amplitude spectral analyses of disorganized patterns on electroencephalograms in preterm infants

The aim of this study is to clarify the differences of EEG activities according to the presence or absence of disorganized patterns using amplitude spectral analysis. We compared EEGs of 17 preterm infants with disorganized patterns with those of 34 matched controls. Amplitude was defined as a square root of EEG power analyzed by fast Fourier transform algorithm, and was calculated in the 9 frequency bands. Six EEG segments of 10 s were collected from the part of EEG with continuous high voltage slow waves in the absence of artifacts. The results were separately evaluated according to the post-conceptional age at EEG recordings. In patients with disorganized patterns, reduced amplitude of delta waves in the central areas and increased amplitude of beta waves in the occipital areas were observed at 29–30 weeks of post-conceptional age. The results were almost similar at 31–32 weeks of post-conceptional age. Amplitude in theta or alpha frequency bands was not different between those with and without disorganized patterns either at 29–30 or 31–32 weeks of post-conceptional age. Amplitude spectral analyses will contribute to objective evaluation of disorganized patterns.     

Early communicative behaviors and their relationship to motor skills in extremely preterm infants

Despite the predictive value of early spontaneous communication for identifying risk for later language concerns, very little research has focused on these behaviors in extremely low-gestational-age infants (ELGA < 28 weeks) or on their relationship with motor development. In this study, communicative behaviors (gestures, vocal utterances and their coordination) were evaluated during mother–infant play interactions in 20 ELGA infants and 20 full-term infants (FT) at 12 months (corrected age for ELGA infants). Relationships between gestures and motor skills, evaluated using the Bayley-III Scales were also examined. ELGA infants, compared with FT infants, showed less advanced communicative, motor, and cognitive skills. Giving and representational gestures were produced at a lower rate by ELGA infants. In addition, pointing gestures and words were produced by a lower percentage of ELGA infants. Significant positive correlations between gestures (pointing and representational gestures) and fine motor skills were found in the ELGA group. We discuss the relevance of examining spontaneous communicative behaviors and motor skills as potential indices of early development that may be useful for clinical assessment and intervention with ELGA infants.     

The link between motor and cognitive development in children born preterm and/or with low birth weight: A review of current evidence

The current review focuses on evidence for a link between early motor development and later cognitive skills in children born preterm or with Low Birth Weight (LBW). Studies with term born children consistently show such a link. Motor and cognitive impairments or delays are often seen in children born preterm or with LBW throughout childhood and studies have established a cross-sectional association between the two. However, it is not yet clear if, and if so, how, motor and cognitive skills are longitudinally interrelated in these children. Longitudinal studies with this population including measures of motor development during the first year of life and cognitive measures at later measurement points were included. The 17 studies included usually show a link between level and/or quality of motor development during the first year of life and later cognitive skills in children born preterm and/or with LBW. However, given the small number of studies, and a possible effect of early interaction between motor and cognitive skills affecting this relation, more work is clearly needed.     

Positive temporal sharp waves in preterm infants with and without brain ultrasound lesions.

OBJECTIVE: Clinical significance of neonatal positive temporal sharp waves (PTS) is controversial. The aim of this work is to study (1) PTS incidence in preterm infants with or without major ultrasound lesion (MUL) per gestational age (GA), and (2) the relationship between PTS in both sleep states and other electroencephalographic (EEG) findings with poor prognoses. METHODS: 97 preterm infants of <27-36 weeks GA, and 12 full-term healthy infants were presented. Prospective study included (1) neurodevelopmental assessment at 40-42 weeks conceptional age (CA), (2) serial neurosonography, and (3) EEG recording at postnatal week 1, 2, 4 and at 40-42 weeks CA. RESULTS: In 50 neonates without MUL, peak PTS was at 31-32 weeks GA. In 47 neonates with MUL, PTS increased significantly from week 2 after birth, descending at the 4th. Neonates of <33 weeks GA with MUL showed significantly increased PTS at term. A significant relationship was found between PTS and other EEG abnormalities with poor neurologic prognoses. PTS incidence varied with sleep states, being predominant in indeterminate sleep in neonates with MUL. CONCLUSIONS: PTS increased significantly in infants with MUL, mainly at week 2 of postnatal life, persisting high until term CA, and correlated with other abnormal EEG findings. SIGNIFICANCE: PTS are highly sensitive to MUL.     

The effects of alternative positioning on preterm infants in the neonatal intensive care unit: A randomized clinical trial

There is a paucity of studies that have investigated the developmental benefits of positioning in the neonatal intensive care unit. The purpose of this study was to investigate the effects of a new, alternative positioning device compared to traditional positioning methods used with preterm infants. In this randomized, blinded clinical trial, one hundred preterm infants (born ≤32 weeks gestation) from a level III neonatal intensive care unit in the United States were enrolled at birth. Participants were randomized to be positioned in the alternative positioning device or to traditional positioning methods for their length of stay in the neonatal intensive care unit. Infants were assessed using the NICU Network Neurobehavioral Scale between 35-40 weeks postmenstrual age. Clinical and feeding outcomes were also captured. Linear and logistic regressions were used to investigate differences in neurobehavioral outcome, feeding performance, and medical outcomes. Infants in the alternative positioning arm of the study demonstrated less asymmetry of reflex and motor responses on the NICU Network Neurobehavioral Scale (p = 0.04; adjusted mean difference = 0.90, 95% CI 0.05–1.75) than those positioned using traditional positioning methods. No other significant differences were observed. Reduction in asymmetry among preterm infants is an important benefit of alternative positioning, as symmetrical movement and responses are crucial for early development. However, it will be important to follow this sample of preterm infants to determine the effects of early positioning on neurodevelopmental outcome in childhood.     

Sleep wake cycling in early preterm infants: Comparison of polysomnographic recordings with a novel EEG-based index

ObjectiveTo document the occurrence of genuine sleep stages in the early preterm babies, and to develop an EEG-based index for following sleep wake cyclicity.MethodsTwelve preterm babies were recruited from a study that assessed ventilator strategies. We used altogether 18 polysomnography recordings that were collected at mean conceptional age of 29.3 (25.9–32.7) weeks. Spontaneous activity transients (SAT) were detected automatically and their cumulative coverage in each 20 s interval was computed from the EEG derivations C3–A2 and O2–A1. Mean SAT% values between sleep stages were compared.ResultsAll babies exhibited all sleep stages, however the sleep was remarkably fragmentary in infants due to their respiratory issues. The EEG index, SAT% showed temporal behavior that strikingly well compared with the sleep stage fluctuations in the hypnogram. In the statistical analysis we found significant differences in all recordings between the deep (quiet) sleep and the REM sleep.ConclusionGenuine sleep states exist in the early preterm babies, and changes in sleep stages are reflected in the EEG activity in a way that can be readily measured by assessing fluctuation of the automatically detected, EEG based index, the SAT%.SignificanceThe findings open a possibility to construct automated analysis or monitoring of sleep wake cyclicity into brain monitors in neonatal intensive care unit.     

Intervention effects on emotion regulation in preterm infants with very low birth weight: A randomize controlled trial

Preterm infants are at risk for emotional difficulties and behavioral problems. This study was aimed to investigate the effects of a clinic-based intervention program (CBIP) and a home-based intervention program (HBIP) compared with a usual care program (UCP) on emotion regulation to stress in preterm infants with very low birth weight (VLBW, birth weight <1500 g). A total of 178 VLBW preterm infants had been previously randomly assigned to receive one of three interventions (57 in CBIP, 63 in HBIP and 58 in UCP). The CBIP and HBIP contained identical child-, parent- and dyad-focused interventions that were provided to infants during hospitalization and were respectively delivered at clinics and at home at PMA 36–38 and 40 weeks, and 1, 2, 4, 6, 9, 12 months of corrected age. All infants were prospectively observed for behavioral reactivity and regulation in response to experimentally evoke stress evoked by a toy-behind-barrier procedure at 12, 18, and 24 months of corrected age. Their cognitive and language abilities, and mothers’ responsiveness were also assessed at 12 months as potential covariates. Compared to the UCP-group infants, the HBIP-group infants exhibited shorter durations of visual orientation to a toy (adjusted difference [95% CI] = −1.60 [−3.07 to −0.13], p = 0.03), and the CBIP-group infants exhibited shorter durations of avoidance (adjusted difference [95% CI] = −0.84 [−1.57 to −0.10], p = 0.03) from 12 to 24 months of corrected age. The CBIP and HBIP showed no difference in the stress reactivity from the UCP, however. These results suggest that comprehensive interventions incorporating child-, parent- and dyad-focused services enhanced VLBW preterm infants’ emotion regulation in response to stress at toddler age.     

Rhythmic EEG patterns in extremely preterm infants: Classification and association with brain injury and outcome

Objective

Classify rhythmic EEG patterns in extremely preterm infants and relate these to brain injury and outcome.

Verification of the ability of the new MRI classification system to predict neurodevelopmental outcome in very low-birth-weight infants

BackgroundVery low-birth-weight infants (VLBWI) are at high risk for adverse neurodevelopmental outcomes. A new, feasible and practical classification system for white matter injury has been reported by Martinez-Biarge et al. Therefore, we investigated the relationship between white matter injury and neurodevelopmental outcomes using this system.Materials and methodsWe enrolled a consecutive series of VLBWI birth weights <1500 g between 2012 and 2015. Two radiologists evaluated the brain MRI obtained in the VLBWI at term-equivalent age. MRI findings were classified into six Grades (Grade 0, Ia, Ib, II, III, IV). The frequency of abnormalities in each Grade was examined. The neurodevelopmental outcome of the VLBWI was assessed at two years or older, and we investigated the presence of cerebral palsy (CP) and intellectual disability (ID), and other serious outcomes. We also calculated the simple kappa value before the raters were matched.ResultsAmong 167 VLBWI, 131 met the eligibility criteria. 114 was Grade 0 (87%), 11 was Grade I (8.4%), 3 was Grade II (2.3%), 1 was Grade III (0.8%), and 2 was Grade IV (1.5%). The frequency of any abnormalities of intelligence in Grade 0 was 24%. The frequency of CP in Grade I was 18%. All Grade III and Grade IV cases had mild CP and an ID. The simple kappa value was 0.95.ConclusionThe prognostic value of the MRI scoring tool was limited. However, all Grade III and Grade IV cases had mild CP and ID. The results demonstrated an excellent inter-rater correlation.     

Cerebellar peduncle injury predicts motor impairments in preterm infants: A quantitative tractography study at term-equivalent age

Purpose

Cerebellar injury is well established as an important finding in preterm infants with cerebral palsy (CP). In this study, we investigated associations between injury to the cerebellar peduncles and motor impairments in preterm infants using quantitative tractography at term-equivalent age, which represents an early phase before the onset of motor impairments.

A randomized controlled trial of clinic-based and home-based interventions in comparison with usual care for preterm infants: Effects and mediators

This study examined the effects and mediators of a clinic-based intervention program (CBIP) and a home-based intervention program (HBIP) compared with usual care in very-low-birth-weight (VLBW) preterm infants on developmental and behavioral outcomes at 24 months of age (corrected for prematurity). In this randomized controlled trial, VLBW preterm infants received either CBIP (n = 57), HBIP (n = 63), or usual care (n = 58) from hospitalization to 12 months. At 12 months, infant emotional regulation was assessed using the toy-behind-barrier procedure and dyadic interaction was observed during free play. At 24 months, infant developmental and behavioral outcomes were assessed using the Bayley Scales of Infant and Toddler Development- 3rd edition and the Child Behavior Checklist for Ages 1.5–5, respectively. Compared with infants under usual care, the CBIP-group infants showed higher cognitive composite scores (difference, 95% confidence interval (CI) = 4.4, 0.8–7.9) and a lower rate of motor delay (odds ratio (OR), 95% CI = 0.29, 0.08–0.99); the HBIP-group infants had lower sleep problem scores (difference, 95% CI = −1.4, −2.5 to −0.3) and a lower rate of internalizing problems at 24 months (OR, 95% CI = 0.51, 0.28–0.93) (all p < .05). The CBIP's effect on cognitive outcome was attenuated when maternal or dyadic interactive behavior was considered; whereas the HBIP's effect on sleep and internalizing behavior was attenuated when duration of orientation to a toy or object was considered. In conclusions, interventions enhanced the cognitive, motor, and behavioral outcomes of VLBW preterm infants. The effects on cognitive and behavioral outcomes might be mediated by early-improved mother–infant interaction and infant emotional regulation, respectively.     

Unstable longitudinal motor performance in preterm infants from 6 to 24 months on the Bayley Scales of Infant Development--Second edition

Preterm birth increases the risk for neurologic and developmental disabilities and therefore long-term follow-up is important. This prospective follow-up study aims to describe longitudinal motor performance in preterm infants from 6 to 24 months and to detect the influence of risk factors on motor performance trajectories.We included preterm infants (n = 348) with a gestational age of ≤32 weeks. The Bayley Scales of Infant Development, 2nd edition (BSID-II) Motor Scale and the Behaviour Rating Scale were recorded at the corrected ages of 6, 12 and 24 months. The Motor Scale raw score was the dependent variable in random coefficient analysis for risk factors in the cohort if infants with cerebral damage were in- and excluded.The raw score increased, showed the highest correlation (r_p = 0.48-0.67) and was more stable than the PDI and its classification. Fifteen percent of the infants had a stable classification, while 45% changed one class. Male sex and intra-ventricular haemorrhage (IVH) lowered the raw scores. Higher motor quality scores and height increased the raw scores, while the influence of maternal education varied at different time points. Removal of infants with cerebral damage from the cohort did not change the risk factors. The results showed that the raw score trajectories were more stable, but after corrections for norm data, the measurements became highly unstable. This is clinically important when reporting results to parents, guiding intervention and in randomised trials. The risk factors predominantly influenced the level of motor performance raw scores. Maternal education additionally influenced the trajectory and should be included in randomisation procedures.     

NMDA receptor antagonist-induced dopamine release in the ventral pallidum does not correlate with motor activation

The ventral pallidum is the output structure of the nucleus accumbens in the ventral corticostriato-thalamocortical loop. Information processing in this loop is critically involved in motor behavior and reinforcement. The ventral pallidum receives a direct dopaminergic input from the ventral tegmental area, but also glutamatergic input from cortical and limbic areas. It has been assumed that dopamine release in the VP is indeed modulated by glutamate. The present study investigated the effects of NMDA receptor blockade on motor behavior and dopamine release in the ventral pallidum. In a first experiment, rats were implanted with microdialysis probes in the ventral pallidum and were systemically injected or locally perfused via the microdialysis probe with dizocilpine (0.32 mg/kg, 10 and 100 microM, respectively). Effects on dopamine and on locomotion were simultaneously monitored. In a second experiment, ventral pallidum was lesioned by quinolinic acid and the effects of systemic dizocilpine (0.08 and 0.16 mg/kg) on locomotion and stereotyped sniffing behavior were determined. It was found that systemic and local dizocilpine administration increased dopamine release in the ventral pallidum to a similar extent whereas only systemic treatment was accompanied by locomotor stimulation. Lesion of the ventral pallidum did not affect locomotion and stereotyped sniffing behavior induced by systemic dizocilpine treatment. Thus, DA release in the ventral pallidum that is elevated by blockade of NMDA receptors is not relevant for activation of motor behavior.