V Pierrat

Ultrasound diagnosis and neurodevelopmental outcome of localised and extensive cystic periventricular leucomalacia

AIMS To compare the ultrasound (US) evolution and neurodevelopmental outcome of infants with localised (grade II) and extensive (grade III) cystic periventricular leucomalacia (c-PVL). METHODS Over a nine year period, c-PVL was diagnosed in 96/3451 (2.8%) infants in two hospital cohorts. Eighteen were excluded from the study. Thirty nine infants with grade II PVL were compared with 39 infants with grade III PVL. RESULTS The two populations were comparable for gestational age and birth weight. In infants with grade II PVL, cysts were noted to develop more often after the first month of life (53%) in contrast with grade III PVL (22%) (odds ratio (OR) 3.81 (95% confidence interval (CI) 1.19 to 12.63)). Cysts were also more often unilateral in grade II (54%) than in grade III PVL (0%) (OR indefinite; RR 3.17 (95% CI 2.16 to 4.64)). At 40 weeks postmenstrual age (PMA), cysts were no longer seen on US in 13/38 infants with grade II PVL, with ventriculomegaly being the only visible sequel in nine cases. In grade III PVL, cysts were still present in 25 of the 27 surviving infants. Nine infants with grade II PVL were free of motor sequelae at follow up compared with one infant with grade III PVL (OR 8.07 (95% CI 0.92 to 181.66)). Twenty two out of 29 children with grade II PVL who developed cerebral palsy achieved independent walking compared with 3/26 with grade III PVL (OR 75 (95% CI 11.4 to 662)). CONCLUSIONS In the cohort studied, 50% of the infants with c-PVL had a more localised form (grade II). In grade II PVL, the cysts developed beyond the first month of life in more than half of the cases and were often no longer visible, on US, at 40 weeks PMA. In order not to miss this diagnosis, sequential US should also be performed beyond the first month of life. Mild ventriculomegaly noted at term can sometimes be due to grade II c-PVL. Cerebral palsy was slightly less common and tended to be less severe in infants with grade II PVL than in those with grade III PVL.

Prognostic value of early somatosensory evoked potentials for adverse outcome in full-term infants with birth asphyxia

SEPs were examined during the first weeks of life in 34 infants with mild to severe birth asphyxia, in an attempt to provide a more accurate prediction of neurodevelopmental outcome. Normal, delayed and absent responses were compared with the infants acute clinical condition, imaging findings using different imaging techniques and neurodevelopmental outcome. All infants with normal SEPs were normal at follow-up. All but two of the infants with a delayed or absent response died or suffered from severe neurological sequelae. A delayed or absent N1 latency carried a risk for death or severe handicap of 71 and 100%, respectively, compared with 25 and 89% for moderate or severe encephalopathy on neurological assessment, and 29 and 85% for moderate or severe changes seen using different imaging techniques. SEPs may provide useful additional information when assessing the infant with birth asphyxia.

Prediction of neurodevelopmental outcome in the preterm infant: short latency cortical somatosensory evoked potentials compared with cranial ultrasound.

One hundred and twenty six preterm infants, with a gestational age of 34 weeks or less, were studied to compare the predictive value of somatosensory evoked potentials (SEPs) with that of cranial ultrasound. A normal N1 latency was no guarantee of a normal outcome, nor did a persistently delayed N1 latency always correlate with a poor outcome. As a predictor of cerebral palsy, SEPs had a sensitivity of 44% and a specificity of 92%. The presence of a large haemorrhage (grade IIb/III) or cystic leukomalacia on cranial ultrasound predicted cerebral palsy with a sensitivity of 73.6% and a specificity of 83.1%. These results demonstrate that the role of SEPs recorded after median nerve stimulation is limited in preterm infants.

Nutritional Status at 2 Years in Former Infants with Bronchopulmonary Dysplasia Influences Nutrition and Pulmonary Outcomes During Childhood

Improved survival rates for extreme prematurity have been accompanied by an increase in the incidence of bronchopulmonary dysplasia (BPD). The objective of this study was to assess factors associated with long-term nutritional and pulmonary function outcomes. The study was a cross-sectional study of 52 children who had been born prematurely, had experienced BPD, and were 4–8 y old at the time of the study. Undernutrition was defined as a Z score for weight-for-height of <–2 SD. Body composition and lung function were evaluated. Resting energy expenditure (REE) was measured using indirect calorimetry. Stepwise logistic regression was used to test for factors associated with undernutrition and pulmonary function. Eighteen children (35%) with BPD, predominantly girls, were undernourished. Undernutrition occurred within the first months of life and was associated with high REE. Multivariate analysis showed that factors significantly associated with undernutrition were female sex and undernutrition at age 2 y. Thirty-one children (60%) had abnormal lung function tests. Multivariate analysis showed that undernutrition at age 2 y was the only factor associated with the risk of developing distension of the airways. Nutritional status at age 2 y in children who had BPD in infancy influences nutritional and pulmonary outcomes in childhood.

Somatosensory evoked potentials in preterm infants with intrauterine growth retardation

In order to further evaluate both the maturation as well as the prognostic value of the somatosensory evoked potentials (SEPs) with regard to neurodevelopmental outcome, SEPs were performed after the first week of life in 56 small-for-gestational age (SGA) preterm neonates. Twenty-five had a prolonged N1 latency while 30 had a normal N1 latency around discharge. One child had an accelerated N1 latency. No correlation was found between the severity of intrauterine growth retardation in relation to birthweight, head circumference or birthweight ratio. None of the children developed cerebral palsy (CP) at follow-up. Developmental quotient (DQ) was calculated in 42 children. The mean DQ of the 21 neonates with an abnormal SEP at discharge was 79.24 +/- 18.56 while the mean DQ of the 21 children with a normal SEP at discharge was 92.52 +/- 11.31. Among the children with a normal N1 latency at discharge the number of breast-fed children was significantly higher than the number of formula-fed neonates (P < 0.05). We conclude that an abnormal SEP around term age in SGA preterm neonates does not imply an increased risk of developing CP. Breast-milk appears to have a beneficial effect on the development of the SEPs in children with intrauterine growth retardation.

Somatosensory Evoked Potentials and Adaptation to Extrauterine Life: A Longitudinal Study

In order to compare longitudinal data with existing cross sectional extrauterine life data on somatosensory evoked potentials (SEPs), two groups of appropriate for gestational age optimal premature infants were studied. Group A consisted of 8 infants born between 34 and 36 weeks gestational age (GA). In this group, SEPs were recorded within 24 hours after delivery and then every 48-72 hours until discharge. Group B consisted of 7 infants born between 29 and 33 weeks GA. In these infants, SEPs were recorded at weekly intervals from the second week onwards. In group A, a marked decreased in the N1 latency was seen during the first week of life. Six infants had initial values above the normal range. During the second week of life this decrease paralleled the cross sectional data. In group B all the infants had a N1 latency within the normal range and the longitudinal data paralleled the cross sectional data. These findings must be taken into consideration when SEPs are used to assess the neurological integrity of the newborn during the first week of life.

Effect of Prenatal Betamethasone/Thyrotropin Releasing Hormone Treatment on Somatosensory Evoked Potentials in Preterm Newborns

ABSTRACT: The maternal administration of betamethasone and thyrotropin releasing hormone (TRH) to accelerate the maturation of the fetus is an increasingly adopted strategy to prevent neonatal morbidity in preterm infants. The effect of this prenatal treatment on the neural maturation of the infant was assessed by measuring somatosensory evoked potentials (SEP) in preterm infants (gestational age 29–36 wk) on the 1st postnatal day, at the age of 1 wk, and before discharge. The N1 latency values of the SEP obtained in 14 infants who were exposed prenatally to betamethasone/TRH were compared with the Nl latencies measured in 12 control infants. On the 1st postnatal day, the N1 latencies in the betamethasone/ TRH-treated infants were strikingly shorter (p < 0.01) than in the controls. However, at the age of 1 wk and at discharge, the N1 latency values of both groups were similar. In conclusion, the present study provides the first solid evidence for the concept that the prenatal exposure to betamethasone/TRH accelerates the SEP-assessed neural maturation of the human fetus, that this prenatal acceleration is followed by a compensatory relative deceleration during the early neonatal period, and that the subsequent SEP-assessed neural maturation proceeds at a normal velocity.

Resting energy expenditure in children with neonatal chronic lung disease and obstruction of the airways.

Children with history of broncho-pulmonary dysplasia (BPD) often suffer from growth failure and lung sequelae. The main objective of this study was to test the role of pulmonary obstruction on resting energy expenditure (REE) and nutritional status in BPD. Seventy-one children with BPD (34 boys and 37 girls) and 30 controls (20 boys and 10 girls) aged 4-8 years were enrolled. Body composition was assessed by bio-impedancemetry measurements; REE was measured by indirect calorimetry. Predicted REE was calculated using the Schofield equation. The population of children with BPD was divided into three groups: children without obstruction of the airways, children with moderate obstruction of the airways, and children with severe obstruction. Children with BPD were significantly smaller and leaner than controls. Altered body composition (reduction of fat mass) was observed in BPD children that suffered from airway obstruction. REE was significantly lower in children with BPD compared to controls, but when adjusted for weight and fat-free mass no significant difference was observed irrespective of pulmonary status. Airway obstruction in children with BPD does not appear to be associated with an increased REE. Moreover altered REE could not explain the altered nutritional status that is still observed in BPD in later childhood. This supports the hypothesis that body composition and pulmonary function in BPD in later childhood are fixed sequelae originating from the neonatal period.