Early cognitive assessment in premature infants: the discriminatory value of eye-tracking vs. Bayley Scales.

Introduction: The testing of visuocognitive development in preterm infants shows strong interactions between perinatal characteristics and cognition, learning and overall neurodevelopment evolution. The assessment of anticipatory gaze data of object-location bindings via eye-tracking can predict the neurodevelopment of preterm infants at the age of 3 years; little is known, however, about the early cognitive function and its assessment methods during the first year of life. Methods: The current study presents data from a novel assessment tool, a Delayed Match Retrieval (DMR) paradigm via eye-tracking was used to measure visual working memory (VWM) and attention skills. The eye-tracking task that was designed to measure infants' ability to actively localize objects and to make online predictions of object-location bindings. 63 infants participated in the study, 39 preterm infants and 24 healthy full term infants - at a corrected age of 8-9 months for premature infants and similar chronological age for full term infants. Infants were also administered the Bayley Scales of Infant and Toddler Development. Results: The analysis of the Bayley scores showed no significant difference between the two groups while the eye-tracking data showed a significant group effect on all measurements. Moreover, preterm infants' VWM performance was significantly lower than full term's. Birth weight affected the gaze time on all Areas Of Interest (AOIs), overall VWM performance and the scores at the Cognitive Bayley subscale. Furthermore, preterm infants with fetal growth restriction (FGR) showed significant performance effects in the eye-tracking measurements but not on their Bayley scores verifying the high discriminatory value of the eye gaze data. Conclusion: Visual working memory and attention as measured via eye-tracking is a non-intrusive, painless, short duration procedure (approx. 4-min) was found to be a significant tool for identifying prematurity and FGR effects on the development of cognition during the first year of life. Bayley Scales alone may not pick up these deficits. Identifying tools for early neurodevelopmental assessments and cognitive function is important in order to enable earlier support and intervention in the vulnerable group of premature infants, given the associations between foundational executive functional skills and later cognitive and academic ability.

Evaluation of cerebral oxygenation and perfusion in small for gestational age neonates and neurodevelopmental outcome at 24-36 months of age.

Objective To examine cerebral oxygenation and perfusion in small for gestational age (SGA) compared with appropriate for gestational age (AGA) neonates during the first postnatal week, and to investigate any association with neurodevelopmental outcomes at 24-36 months of age. Methods A prospective matched case-control study was conducted evaluating cerebral oxygenation and perfusion, using near-infrared spectroscopy (NIRS), between SGA and AGA neonates, during the first postnatal week. A neurodevelopmental assessment with Bayley-III was performed at 24-36 months of age. Results Forty-eight SGA and 48 AGA neonates of similar gestation (32.8 ± 2.1 vs. 32.5 ± 1.9) were enrolled. On the first postnatal day, the cerebral oxygenation was equal between SGA and AGA neonates (71 ± 7% vs. 72 ± 8%); however, in the subgroup analysis, males had higher oxygenation compared to female SGA neonates (73 ± 7% vs. 69 ± 7%, P = 0.04). Cerebral perfusion was significantly higher in SGA neonates on the first postnatal day (1.4 ± 0.6 vs. 1.1 ± 0.5, P = 0.04), but this difference was diminished on subsequent measurements. There were no significant differences between the SGA and AGA infants regarding the composite cognitive, communication and motor index scores. The length of mechanical ventilation and late-onset sepsis were significant risk factors affecting the cognitive and communication composite index scores, respectively. Conclusion Cerebral oxygenation was equal between SGA and AGA neonates, while cerebral perfusion was transiently increased in SGA neonates during the first postnatal day. There was no significant association of cerebral oxygenation and perfusion with neurodevelopmental outcomes.

The association of the cerebral oxygenation during neonatal sepsis with the Bayley-III Scale of Infant and Toddler Development index scores at 18-24 months of age.

BACKGROUND: Neonatal sepsis has been associated with poor neurodevelopmental outcome, however the evidence regarding the exact mechanism of the inflammation to the developing neonatal brain are inconclusive. AIMS: To investigate association between cerebral oxygenation during neonatal sepsis and neurodevelopmental outcome. STUDY DESIGN: Follow-up assessment of a previously described prospective case-control study. SUBJECTS: A cohort of late preterm (34-37 weeks' gestation) and preterm (<34 weeks' gestation) infants with sepsis and healthy controls, evaluated at 18-24 months of corrected gestational age with Bayley-III Scales for Infant and Toddler Development (BSID-III). OUTCOME MEASURES: To evaluate the association between cerebral tissue oxygenation index (cTOI) and fractional tissue oxygen extraction (FTOE), measured with near-infrared spectroscopy, during sepsis and the composite cognitive and motor index scores. RESULTS: Thirty-one infants with blood culture confirmed neonatal sepsis and thirty-five controls were recruited. The cerebral oxygenation was significantly lower in septic neonates, compared to controls (61 ±â€¯7 compared to 72 ±â€¯5; p < 0.001). Infants with sepsis had significantly lower cognitive and motor index scores and higher proportion of suboptimal cognitive (16% compared to 3%, p = 0.045) and motor (16% compared to none, p = 0.008) index score. The low mean cTOI and FTOE noted in septic infants were significantly associated with worse cognitive and motor composite index scores. CONCLUSIONS: Infants with lower cerebral oxygenation during neonatal sepsis are at increased risk of worse cognitive and motor scores in the neurodevelopmental assessment.

Early caloric deprivation in preterm infants affects Bayley-III scales performance at 18-24 months of corrected age.

BACKGROUND: Adequate nutrition is essential for optimal neurodevelopment to preterm infants. Our aim was to evaluate the impact of caloric deprivation on Bayley-III scales performance at 18-24 months of corrected age, in a cohort of preterm infants. METHODS: We prospectively enrolled infants with gestational age <30 weeks and birth weight <1500 g. Apart from a whole cohort analysis, we performed a subgroup analysis between infants received inadequate calories (<85 Kcal/kg/day) during the first two weeks of age, compared to a standard nutrition group. All infants underwent a Bayley-III assessment at 18-24 months of corrected age. RESULTS: From the 63 preterm infants analysed, 25% had caloric deprivation compared to 75% with adequate nutrition. Caloric deprived infants were of lower gestational age and birth weight, and received a lower amount of enteral feeding during the first 14 days of age. There were no differences between the two groups regarding the common neonatal co-morbidities. Caloric deprived infants had significantly lower composite index scores at 18-24 months of corrected age. Caloric deprivation, late onset sepsis, necrotizing enterocolitis, and bronchopulmonary dysplasia were significant risk factors of neurodevelopmental impairment. CONCLUSIONS: Several neonatal factors affect the neurodevelopmental outcome of preterm infants, and nutrition may pose an important role.