Ultrasound measurements of brain structures differ between moderate-late preterm and full-term infants at term equivalent age

Background: Brain growth in moderate preterm (MP; gestational age (GA) 32+0–33+6 weeks) and late preterm infants (LP; GA 34+0–36+6 weeks) may be impaired, even in the absence of brain injury. Aims: The aims of this study were to assess brain measurements of MP and LP infants, and to compare these with full-term infants (GA > 37 weeks) using linear cranial ultrasound (cUS) at term equivalent age (TEA). Study design: cUS data from two prospective cohorts were combined. Two investigators performed offline measurements on standard cUS planes. Eleven brain structures were compared between MP, LP and full-term infants using uni- and multivariable linear regression. Results were adjusted for postmenstrual age at cUS and corrected for multiple testing. Results: Brain measurements of 44 MP, 54 LP and 52 full-term infants were determined on cUS scans at TEA. Biparietal diameter and basal ganglia-insula width were smaller in MP (−9.1 mm and − 1.7 mm, p < 0.001) and LP infants (−7.0 mm and − 1.7 mm, p < 0.001) compared to full-term infants. Corpus callosum – fastigium length was larger in MP (+2.2 mm, p < 0.001) than in full-term infants. No significant differences were found between MP and LP infants. Conclusions: These findings suggest that brain growth in MP and LP infants differs from full-term infants. Whether these differences have clinical implications remains to be investigated

Incidence of brain lesions in moderate-late preterm infants assessed by cranial ultrasound and MRI: The BIMP-study

PURPOSE: To evaluate the incidence and characteristics of brain lesions in moderate-late preterm (MLPT) infants, born at 32-36 weeks' gestation using cranial ultrasound (cUS) and magnetic resonance imaging (MRI). METHODS: Prospective cohort study carried out at Isala Women and Children's Hospital between August 2017 and November 2019. cUS was performed at postnatal day 3-4 (early-cUS), before discharge and repeated at term equivalent age (TEA) in MLPT infants born between 32+0 and 35+6 weeks' gestation. At TEA, MRI was also performed. Several brain lesions were assessed e.g. hemorrhages, white matter and deep gray matter injury. Brain maturation was visually evaluated. Lesions were classified as mild or moderate-severe. Incidences and confidence intervals were calculated. RESULTS: 166 MLPT infants were included of whom 127 underwent MRI. One or more mild lesions were present in 119/166 (71.7 %) and moderate-severe lesions in 6/166 (3.6 %) infants on cUS and/or MRI. The most frequent lesions were signs suggestive of white matter injury: inhomogeneous echogenicity in 50/164 infants (30.5 %) at early-cUS, in 12/148 infants (8.1 %) at TEA-cUS and diffuse white matter signal changes (MRI) in 27/127 (23.5 %) infants. Cerebellar hemorrhage (MRI) was observed in 16/127 infants (12.6 %). Delayed maturation (MRI) was seen in 17/117 (13.4 %) infants. Small hemorrhages and punctate white matter lesions were more frequently detected on MRI than on cUS. CONCLUSIONS: In MLPT infants mild brain lesions were frequently encountered, especially signs suggestive of white matter injury and small hemorrhages. Moderate-severe lesions were less frequently seen

Neurological Surveillance in Moderate-Late Preterm Infants—Results from a Dutch–Canadian Survey

Preterm birth remains an important cause of abnormal neurodevelopment. While the majority of preterm infants are born moderate-late preterm (MLPT; 32–36 weeks), international and national recommendations on neurological surveillance in this population are lacking. We conducted an observational quantitative survey among Dutch and Canadian neonatal level I–III centres (June 2020–August 2021) to gain insight into local clinical practices on neurological surveillance in MLPT infants. All centres caring for MLPT infants designated one paediatrician/neonatologist to complete the survey. A total of 85 out of 174 (49%) qualifying neonatal centres completed the survey (60 level I–II and 25 level III centres). Admission of MLPT infants was based on infant-related criteria in 78/85 (92%) centres. Cranial ultrasonography to screen the infant’s brain for abnormalities was routinely performed in 16/85 (19%) centres, while only on indication in 39/85 (46%). In 57/85 (67%) centres, neurological examination was performed at least once during admission. Of 85 centres, 51 (60%) followed the infants’ development post-discharge, with follow-up duration ranging from 1–52 months of age. The survey showed a wide variety in neurological surveillance in MLPT infants among Dutch and Canadian neonatal centres. Given the risk for short-term morbidity and long-term neurodevelopmental disabilities, future studies are required to investigate best practices for in-hospital care and follow-up of MLPT infants