Infant's Behaviour Checklist for low birth weight infants and later neurodevelopmental outcome.

Assessment of the characteristics of spontaneous movements and behaviour in early infancy helps in estimating developmental outcomes. We introduced the Infant Behaviour Checklist (IBC) and examined the relationship between the behavioural characteristics of low-birth-weight infants and neurodevelopmental outcomes at 6 years of age. The behavioural characteristics during the neonatal (36-43 weeks, adjusted) and early infancy periods (49-60 weeks, adjusted) were assessed in very-low-birth-weight infants. The IBC includes 44 common behaviours. We assessed the appearance of individual behavioural characteristics at each period according to the neurodevelopmental outcome. Of the 143 infants assessed during the neonatal period, 89 had typical development (TD), 30 had intellectual disability (ID), and 24 had autism spectrum disorder (ASD). In 78 infants assessed during early infancy, 40, 21, and 17 had TD, ID, and ASD, respectively. The frequency of appearance of three behaviour-related items was significantly lower in the ID group than in the TD group. The frequency of appearance of three posture- and behaviour-related items was significantly lower, while that of two posture-related items was significantly higher, in the ASD group than in the TD group. Behavioural assessment using the IBC may provide promising clues when considering early intervention for low-birth-weight infants.

Early motor signs of autism spectrum disorder in spontaneous position and movement of the head.

We examined the characteristics of spontaneous movements at 9-20 weeks postterm age in very low birth-weight infants who later developed autism spectrum disorder (ASD). We analyzed video recordings of spontaneous movements of 39 children who had no clinical issues [typically developing (TD) group], 21 children who showed developmental delay, and 14 children who were diagnosed with ASD (ASD group) at 6 years of age. Head position in each video frame was classified by visual inspection. The percentage of midline head position (PMHP) and number of changes in head position were calculated. Spontaneous limb movements were quantified using six indices. The values of PMHP were significantly lower in the ASD group than in the TD group. The lower PMHP during early infancy is associated with later development of ASD. Poorer performance in maintaining midline position of the head at this period may distinguish infants who later develop ASD from those who show TD.

Early standard development assessment characteristics in very low birth weight infants later classified with autism spectrum disorder.

BACKGROUND: The prevalence of autism spectrum disorder (ASD) symptoms is high among very low birth weight infants (VLBWIs). Early diagnosis of ASD is crucial, because early intervention for ASD is effective. OBJECTIVE: To evaluate early standard development assessment characteristics in VLBWIs later classified with ASD. METHODS: Thirty-five VLBWIs later diagnosed with ASD were compared with 169 children with typical development who were admitted to the neonatal intensive care unit at Nagano Children's Hospital between 2001 and 2005. We retrospectively evaluated developmental quotient (DQ) using the Kyoto Scale of Psychological Development (KSPD) at 6 and 18months post-term age (PTA) and 3year chronological age. RESULTS: KSPD DQ was significantly lower in ASD infants than in typical development infants at all ages. Postural-motor DQs of ASD infants at 18months PTA and 3year chronological age showed some increase compared to that at 6months PTA. CONCLUSION: Early recognition of ASD using standardized development assessment tools in VLBWIs might be possible.

Jerky spontaneous movements at term age in preterm infants who later developed cerebral palsy.

BACKGROUND: Assessment of spontaneous movements in infants has been a powerful predictor of cerebral palsy (CP). Recent advancements on computer-based video analysis can provide detailed information about the properties of spontaneous movements. AIMS: The aim of this study was to investigate the relationship between spontaneous movements of the 4 limbs at term age and the development of CP at 3 years of age by using a computer-based video analysis system. STUDY DESIGN AND SUBJECTS: We analyzed video recordings of spontaneous movements at 36-44 weeks postmenstrual age (PMA) for 145 preterm infants who were born preterm (22-36 weeks PMA with birthweights of 460-1498g). Sixteen of the infants developed CP by 3 years of age, while 129 developed normally. We compared 6 movement indices calculated from 2-dimensional trajectories of all limbs between the 2 groups. RESULTS: We found that the indices of jerkiness were higher in the CP group than in the normal group (p<0.1 for arms and p<0.01 for legs). No decline was observed in the average velocity and number of movement units in the CP group compared with to the normal group. CONCLUSIONS: Jerkiness of spontaneous movements at term age provides additional information for predicting CP in infants born preterm.

Specific characteristics of spontaneous movements in preterm infants at term age are associated with developmental delays at age 3 years.

AIM: The aim of this study was to investigate the relationship between the characteristics of spontaneous movements in preterm infants at term age and developmental delay at 3 years of age. METHOD: We analysed video recordings of the spontaneous movements in the supine position of 124 preterm infants (44 males, 80 females) at 36 to 44 weeks postmenstrual age (PMA). The infants were born preterm (22-36wks PMA; birthweight 489-1696g) and had not received a diagnosis of a neurological or developmental disorder by the age of 3 years. The recorded spontaneous movements were quantified using six movement indices, which were calculated from two-dimensional trajectories of all limbs. The infants were divided into three developmental groups, normal, borderline, or delayed, based on their developmental quotient as calculated using the Kyoto Scale of Psychological Development 2001 (Kyoto Scale) at 3 years of age. Group differences in the movement indices were analysed. RESULTS: In the delayed group, average velocity of arms and legs were significantly lower (p<0.05 and p<0.01 respectively), the numbers of movement units of arms and legs were significantly lower (p<0.05 and p<0.01 respectively), kurtosis of acceleration of arms and legs was significantly higher (p<0.05 in each case), and correlation between limb velocities was higher (p<0.05) than in the normal group. INTERPRETATION: In children who exhibited developmental delay at 3 years of age, the spontaneous movements at term age can be described as less active with intermittent occurrences of abrupt and synchronized movements of the limbs. Recognition of these characteristics of spontaneous movements at term age may be used as a predictor for subsequent cognitive and behavioural development in preterm infants.

Qualitative brain MRI at term and cognitive outcomes at 9 years after very preterm birth.

OBJECTIVE: A prospective study was performed to assess the relationship between the appearance of cerebral MRI at term and the cognitive functioning at 9 years old in very preterm born infants. METHODS: Seventy-six very preterm born infants (birth weight <1500 g or gestational age ≤32 weeks) obtained cerebral MRI at term-equivalent period, which was assessed by using established composite scores for the white and gray matter; cognitive outcomes at 9 years old were assessed in 60 subjects by using Wechsler Intelligence Scale for Children, Third Edition. RESULTS: Mildly low scores on the different IQ indices (<85) were observed in 23.3% (verbal IQ), 41.7% (performance IQ), and 30.0% (full-scale IQ) of the cohort, whereas moderately low scores (<70) were noted in 3.3% (verbal IQ), 11.7% (performance IQ), and 11.7% (full-scale IQ); cerebral palsy was diagnosed in 10.0%, whereas special assistance at school was required in 56.7%. Abnormal white matter appearances predicted mildly low verbal, performance, and full-scale IQs; moderately low performance and full-scale IQs; cerebral palsy; and the requirement for special assistance at school. Abnormal white matter appearances predicted mild cognitive impairment even after the adjustment for known clinical risk factors. In contrast, abnormal gray matter appearances did not predict any of the outcome measures. CONCLUSIONS: In a cohort of very preterm born infants, abnormal white matter appearance on term MRI showed consistent associations with cognitive impairments at 9 years old, further supporting the benefit of obtaining term MRI for very preterm born infants.

Neurodevelopmental outcomes of very low birth weight and extremely low birth weight infants at 18 months of corrected age associated with prenatal risk factors.

BACKGROUND: Very premature infants occasionally have neurodevelopmental disabilities. However, there have been quite limited data on prenatal risk factors associated with their neurodevelopmental outcomes. AIM: To clarify the relationship between prenatal risk factors and neurodevelopmental outcomes of very premature infants. STUDY DESIGN: The study design is a retrospective review. SUBJECTS: One hundred seventy Japanese women with a singleton pregnancy and their infants whose birth weight being less than 1500 g were included. We classified those infants into 118 appropriate for gestational age (AGA) and 52 small for gestational age (SGA) infants. OUTCOME MEASURES: Infants' neurodevelopmental outcomes at 18 months of corrected age were evaluated by the Kyoto Scale of Psychological Development 2001 (KSPD). We analyzed and compared the infants' outcomes and prenatal risk factors between two groups. RESULTS: Mortality and rate of infants unevaluable by KSPD because of severe impairment were not significantly different between those groups. However, the developmental quotient score of the cognitive-adaptive area in SGA infants born between 25 and 31 weeks of gestation was significantly lower than that in AGA infants randomly selected as gestation-matched controls. More advanced gestational age and heavier birth weight protected against adverse neurodevelopmental outcomes in both groups. Moreover, male infants were related to the excess risk of adverse neurodevelopmental outcomes in the SGA group. CONCLUSION: In view of the neurodevelopment of the infants, it seems that the most efficient obstetric strategy for improving prognosis of premature infants should be targeted to prolong the pregnancy period as long as the reassuring fetal status and maternal stable health condition are being confirmed.

Abnormal white matter appearance on term FLAIR predicts neuro-developmental outcome at 6 years old following preterm birth.

UNLABELLED: Preterm infants are at significant risk of neuro-developmental disorders at school-age. MRI is a potentially useful screening tool of such disorders. Using FLAIR imaging in the preterm infants at term, here we demonstrate that abnormal low-intensity signal in the white matter predicts the neuro-developmental outcome at 6 years. STUDY DESIGN: Clinical factors associated with white matter appearance on MRI obtained at term were investigated in 210 preterm infants. RESULTS: Low-intensity signal on FLAIR imaging was commonly observed (69%) at <2 months corrected-age. Its incidence correlated with corrected-age at scan, maternal pyrexia and cystic periventricular leukomalacia. Low-intensity signal on FLAIR significantly correlated with performance and full-scale developmental quotients, whereas diffuse high-intensity signal on T2-weighted imaging correlated only with the full-scale developmental quotient at 6 years (n = 75, WISC-R). FLAIR imaging, but not T2-weighted imaging, predicted mild neuro-developmental delay. CONCLUSIONS: FLAIR appeared to detect subtle white matter injury related with neuro-developmental disorders at school-age, whereas T2-weighted imaging seemed to identify relatively more severe injury. FLAIR is a potentially sensitive screening tool that is readily available and easily interpretable.

Periventricular low intensities on fluid attenuated inversion recovery imaging in the newborn infant: Relationships to chronic white matter lesions.

BACKGROUND: Neurological disadvantages due to hypoxic ischemic encephalopathy (HIE) are still very serious problems. In order to support the infant with HIE, it is important to evaluate the severity of the brain injury early. The authors performed a magnetic resonance imaging (MRI) study of the neonatal brain in order to assess the clinical value of periventricular low intensities (PVLI) detected on fluid attenuated inversion recovery (FLAIR) imaging. METHODS: A total of 451 MRI from 167 preterm and 113 term infants were sorted into groups according to the corrected age at the time of scanning. Intensities in the white matter were then divided into five grades according to the severity of the finding on FLAIR imaging. Chronic abnormalities such as periventricular hyperintensities (PVHI) were also analyzed. RESULTS: In early MRI, which was obtained before 2 months corrected age, the incidence of PVLI was 63%, while it was only 3% and 0% in the middle (2-8 months) and the late (8-18 months) scans, respectively. Instead of PVLI, PVHI were commonly observed both on late FLAIR imaging (89%) and late T2-weighted imaging (72%). The severity of the white matter damage diagnosed on early FLAIR imaging had a significant correlation with that of late FLAIR imaging. CONCLUSIONS: F-PVLI on early FLAIR imaging would be a good predictor of chronic white matter damage. FLAIR imaging would be also useful in follow-up of infants because of its high sensitivity to the chronic white matter lesion.

Periventricular low intensities on fluid attenuated inversion recovery imaging in the newborn infant: relationships to the clinical data and long-term outcome.

BACKGROUND: The author's previous study showed that it is possible to predict the severity of white matter injury in early infancy by using fluid attenuated inversion recovery (FLAIR) imaging. A follow-up study was performed in order to assess the correlation between the incidence of periventricular low intensities on FLAIR imaging (F-PVLI) and the clinical data including the physiological variables at birth and the long-term outcome of the infant. METHODS: The authors reviewed MRI of 328 newborn infants, which were obtained before 2 months corrected age. Abnormal findings in the periventricular white matter and other part of the brain were recorded. Periventricular abnormal intensities were sorted into four groups according to the FLAIR grade, which comprised normal, F-PVLI 1 (focal), F-PVLI 2 (extensive), cystic periventricular leukomalacia (C-PVL), and diffused leukomalacia. RESULTS: Significantly more periventricular abnormal intensities were detected by FLAIR imaging than by conventional T1 and T2 weighted imaging. In the groups of F-PVLI 2 and C-PVL, the birth weight (BW), gestational age (GA), blood pH and base excess at birth were significantly lower than in the normal group. However, when the study population was defined into very low birth weight infants, F-PVLI 2 had significantly larger BW and GA than normal. The FLAIR grade had a strong correlation with the developmental outcome at 12 and 36 months corrected age. CONCLUSIONS: F-PVLI is a silent but very important white matter injury, which has many features in common with C-PVL. FLAIR imaging could be a strong tool in screening newborn infants at high risk of neurological impairment.