Moderate hypothermia in neonates with hypoxic-ischaemic encephalopathy might improve survival and neurological outcomes at up to 18 months of age, although complete neurological assessment at this age is difficult. To ascertain more precisely the effect of therapeutic hypothermia on neonatal cerebral injury, we assessed cerebral lesions on MRI scans of infants who participated in the Total Body Hypothermia for Neonatal Encephalopathy (TOBY) trial. In the TOBY trial hypoxic-ischaemic encephalopathy was graded clinically according to the changes seen on amplitude integrated EEG, and infants were randomly assigned to intensive care with or without cooling by central telephone randomisation. The relation between allocation to hypothermia or normothermia and cerebral lesions was assessed by logistic regression with perinatal factors as covariates, and adjusted odds ratios (ORs) were calculated. The TOBY trial is registered, number ISRCTN 89547571. 325 infants were recruited in the TOBY trial between 2002 and 2006. Images were available for analysis from 131 infants. Therapeutic hypothermia was associated with a reduction in lesions in the basal ganglia or thalamus (OR 0.36, 95% CI 0.15-0.84; p=0.02), white matter (0.30, 0.12-0.77; p=0.01), and abnormal posterior limb of the internal capsule (0.38, 0.17-0.85; p=0.02). Compared with non-cooled infants, cooled infants had fewer scans that were predictive of later neuromotor abnormalities (0.41, 0.18-0.91; p=0.03) and were more likely to have normal scans (2.81, 1.13-6.93; p=0.03). The accuracy of prediction by MRI of death or disability to 18 months of age was 0.84 (0.74-0.94) in the cooled group and 0.81 (0.71-0.91) in the non-cooled group. Therapeutic hypothermia decreases brain tissue injury in infants with hypoxic-ischaemic encephalopathy. The predictive value of MRI for subsequent neurological impairment is not affected by therapeutic hypothermia. UK Medical Research Council; UK Department of Health.

Poor postnatal growth after preterm birth does not match the normal rapid growth in utero and is associated with preterm morbidities. Insulin‐like growth factor 1 (IGF‐1) axis is the major hormonal mediator of growth in utero, and levels of IGF‐1 are often very low after preterm birth. We reviewed the role of IGF‐1 in foetal development and the corresponding preterm perinatal period to highlight the potential clinical importance of IGF‐1 deficiency in preterm morbidities.Conclusion: There is a rationale for clinical trials to evaluate the potential benefits of IGF‐1 replacement in very preterm infants.

Children born prematurely have a high incidence of visual disorders which cannot always be explained by focal retinal or brain lesions. The aim of this study was to test the hypothesis that visual function in preterm infants is related to the microstructural development of white matter in the optic radiations. We used diffusion tensor imaging (DTI) with probabilistic diffusion tractography to delineate the optic radiations at term equivalent age and compared the fractional anisotropy (FA) to a contemporaneous evaluation of visual function. Thirty-seven preterm infants (19 male) born at median (range) 28⁺⁴ (24⁺¹–32⁺³) weeks gestational age, were examined at a post-menstrual age of 42 (39⁺⁶–43) weeks. MRI and DTI were acquired on a 3 Tesla MR system with DTI obtained in 15 non-collinear directions with a b value of 750 s/mm². Tracts were generated from a seed mask placed in the white matter lateral to the lateral geniculate nucleus and mean FA values of these tracts were determined. Visual assessment was performed using a battery of nine items assessing different aspects of visual abilities. Ten infants had evidence of cerebral lesions on conventional MRI. Multiple regression analysis demonstrated that the visual assessment score was independently correlated with FA values, but not gestational age at birth, post-menstrual age at scan or the presence of lesions on conventional MRI. The occurrence of mild retinopathy of prematurity did not affect the FA measures or visual scores. We then performed a secondary analysis using tract-based spatial statistics to determine whether global brain white matter development was related to visual function and found that only FA in the optic radiations was correlated with visual assessment score. Our results suggest that in preterm infants at term equivalent age visual function is directly related to the development of white matter in the optic radiations.