Silvia Pisoni

Visual performance and brain structures in the developing brain of pre-term infants

The presence of abnormal visual function has been related to overt lesions in the thalami, peritrigonal white matter (such as cavitational-necrotic periventricular leucomalacia) and optic radiations, and also to the extent of occipital cortex involvement. The normal development of visual function seems to depend on the integrity of a network that includes not only optic radiations and the primary visual cortex but also other cortical and subcortical areas, such as the frontal or temporal lobes or basal ganglia, which have been found to play a topical role in the development of vision. Therefore, the complex functions and functional connectivity of the developing brain of premature infants can be studied only with highly sophisticated techniques such as diffusion tensor tractography. The combined use of visual tests and neonatal structural and functional neuroimaging, which have become available for newborn infants, provides a better understanding of the correlation between structure and function from early life. This appears to be particularly relevant considering the essential role of early visual function in cognitive development. The identification of early visual impairment is also important, as it allows for early enrolment in intervention programmes. The association of clinical and functional studies to newer imaging techniques, which are being increasingly used also in neonates, are likely to provide further information on early aspects of vision and the mechanisms underlying brain plasticity, which are still not fully understood. Early exposure to a difficult postnatal environment together with early and unexpected removal from a protective milieu are exclusive and peculiar factors of prematurity that interfere with the normal development of the visual system in pre-term babies. The problem is further compounded by the influence of different perinatal brain lesions affecting the developing brain of premature babies. Nevertheless, in the last few decades, there have been considerable advances in our understanding of the development of vision in pre-term infants during early infancy. This has mainly been due to the development of age-specific tests assessing various aspects of visual function, from ophthalmological examination to more cortical aspects of vision, such as the ability to process orientation or different aspects of visual attention [1-7]. Improvements in understanding very early and specific neurological impairments in neurological functions have been reported in pre-term infants, known to be at risk of developing visual and visual-perceptual impairment. These impairments are due not only to retinopathy, a common finding in premature infants, but also to cerebral (central) visual impairment, secondary to brain lesions affecting the central visual pathway.

Perceptual-motor abilities in pre-school preterm children

BACKGROUND Several studies report a high percentage of premature infants presenting perceptual motor difficulties at school age. The new version of the Movement Assessment Battery for Children allows the assessment of perceptual-motor abilities in children from the age of 3years. AIMS To evaluate early perceptual-motor abilities in prematurely born children below the age of 4years. STUDY DESIGN The Movement Assessment Battery for Children 2nd edition was administered to 105 low-risk prematurely born children (<32weeks gestation) and in a control group of 105 term-born children matched for age and sex. All children were assessed between the age of 3years and 3years-11months. RESULTS 63 children (60%) had total scores above the 15th percentile, 15 (14.3%) had scores between the 5th and the 15th percentile, and 13 (12.4%) below the 5th percentile. The remaining 14 children (13.3%) refused to perform or to complete the test. The difference between preterm and control group was significant for total scores, Manual Dexterity and Aiming and Catching scores. In the preterm group there was a correlation between age at testing, total scores and Aiming and Catching subscores. The Movement ABC-2 subscores were significantly lower in children born below 29weeks. CONCLUSION Perceptual-motor difficulties can already be detected on the assessment performed before the age of 4years. Prematurely born children assessed between 3years and 3years-3months appeared to have more difficulties in performing the test than the older ones or their age matched term-born peers. These findings support the possibility of a delayed maturation in the younger age group.

Emerging executive skills in very preterm children at 2 years corrected age: A composite assessment

Executive Function (EF) deficits have previously been identified in preterm children. However, only recently have emerging executive functions been studied in preschool children who were born preterm without major brain damage. Our study provides a broad assessment of EFs in 72 extremely preterm births (gestational age < 34 weeks and birth weight < 2500 g) and 73 full-term children, born between 2006 and 2008, at 24 months of corrected age. Three factors were extracted from the EF administered measures: working memory, cognitive flexibility, and impulsivity control. Only cognitive flexibility was found to discriminate preterm children from controls.

Total body cooling: skin and renal complications

Subcutaneous fat necrosis (SFN) is a rare, self-limiting panniculitis mostly reported in infancy and childhood. Newborns and infants have a greater saturated to unsaturated fats ratio in their subcutaneous fat compared with older children and adults, causing an increased tendency to crystallise with cold stress.1 A full-term baby suffering hypoxic …

Cranial ultrasound screening in late preterm infants

Late preterm births have enormously increased in the last decades and there is mounting evidence showing that infants born late preterm are less healthy than infants born at term [1] and they are more likely to develop neonatal morbidities (temperature instability, respiratory distress syndrome, excessive weight loss and dehydration requiring intravenous infusion, sepsis, hypoglycemia and jaundice requiring phototherapy) [2]. More recently, an increased neuromorbidity has been documented and long-term neurodevelopmental impairments (poor school performance, early intervention services, special education needs) have been reported in this population [3,4]. The neuromorbidity of the late preterm infants has been attributed to both the potential detrimental neurological effects (extrinsic vulnerability) of the morbidities these babies experience in the neonatal period, and to the intrinsic brain vulnerability. Advances in neuroimaging techniques have highlighted a higher intrinsic vulnerability of the late preterm brain due to the structural and molecular immaturity of the developing brain at specific gestational ages [5,6]. Therefore, late preterm infants have a risk to develop brain lesions which is lower than more premature babies but higher than term newborns and they can be affected by brain lesions common to both preterm and term infants [7]. However, the incidence of brain abnormalities in this specific population has never been investigated as late preterm infants have long been considered a large and low-risk population. Considering that most of the brain lesions are clinically subtle or silent during the neonatal period, a cranial ultrasound screening may play a role in: 1. detecting babies at risk of impaired neurodevelopment later in childhood and who may benefit from early intervention programs; 2. identifying the most significant perinatal risk factors associated with brain abnormalities in such a large low-risk population in order to target the potential need for cranial ultrasound at birth. Based on these assumptions we performed a cranial ultrasound screening project on late preterm infants. Our preliminary data (unpublished data) suggest that lower gestational age, within the late preterm period, and early neonatal morbidities, can provide an indication at birth to undergo a cranial ultrasound scan as they are associated with a higher risk to develop brain abnormalities. Late preterm infants represent a vulnerable population and investigation and follow-up program should be modulated according to the prenatal, perinatal and postnatal characteristics. Follow-up studies are needed to correlate neonatal ultrasound findings with long-term neurobehavioral outcomes in late preterm infants.

1222 Neurocognitive Outcome at 3 Years in Extremely Low Birth Weight Infants (VLBW) with Cerebellar Hemorrhage (CH)

Introduction CH is an increasingly diagnosticated problem in VLBW, reaching up till 19% among the ELBW due to improved neuroimaging techniques and increased VLBW survivors. The impact of CH on long-term neurodevolopmental outcome is still not well known. Aim To evaluate the consequences of CH on neurocognitive outcome in VLBW. Methods CH and other brain lesions were identified by MRI performed at TEA. The neurological development quotient (DQ) of 9 ELBW infants with CH, without white matter (WM) lesions (median GA- 25wks, range 23–27; birth weight -BW- 710 g, 425–980), was compared with the DQ of others two groups: 43 control VLBW infants without lesions (GA 27.7 wks, 23–33; BW 780 g, 430–1000) and 8 VLBW babies with WM major abnormalities (GA 28.7 wks, 26–32; BW 725 g, 430–970). The DQ was evalueted at the age of 3 years with the Griffiths Mental Developmental Scales (GMDS). Results The 3 groups were comparable for BW (p=0.088), but not for GA (p=0.005). The CH group, compared with controls, showed: a lower not significant DQ score (p 0.07), a significant lower score in the motor areas (locomotor p=0.006, eye and hand-coordination p=0.002, performance p=0.014) and in the personal social skill (p=0.05), not in language (p=0.13) and pratical reasoning (p=0–38). When compared to the WM lesions group not significant difference was found in the DQ and the other areas. Conclusions Our data showed that CH plays an important role mainly in the motor and behavioral dysfunctions at long-term outcome in VLBW infants.