Cranial ultrasound evaluation in term neonates

COL4A1 gene mutations and perinatal intracranial hemorrhage in neonates: case reports and literature review

Intracranial hemorrhage may represent a complication of the perinatal period that affects neonatal morbidity and mortality. Very poor data exist about a possible association between mutations of the type IV collagen a1 chain (COL4A1) gene and the development of intracranial hemorrhage, and only sporadic reports focus on intracerebral bleedings already developing in utero or in the neonatal period in infants with such a mutation. This study presents a case series of term neonates affected by intracranial hemorrhage, with no apparent risk factors for the development of this condition, who were carriers of COL4A1 gene variants. This study also provides a review of the most recent scientific literature on this topic, specifically focusing on the available scientific data dealing with the perinatal period.

Assessment of role of cranial ultrasound (CUS) in the evaluation of high-risk preterm and term neonates

Background

Cranial ultrasonography (CUS) has become an important tool to depict normal brain anatomy and to detect the ischemic and hemorrhagic brain injury patterns in high-risk neonates. The present study aimed to assess the utility of CUS to diagnose the spectrum of brain injury patterns in high-risk preterm and term neonates admitted to the neonatal intensive care unit (NICU) and to find the association of CUS findings in various adverse antenatal and perinatal feto-maternal factors.

Results

Out of the 200 neonates, 76 (38%) neonates had abnormal CUS findings and 124 (62%) had a normal CUS. Germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) (28/76; 36.8 %) was the commonest abnormality with GMH (grade 1) in 14/76 (18.4%), grade 2 in 7 (9.2%), grade 3 in 5 (6.5%), and grade 4 in 2 (2.63%). The other findings observed were cerebral edema (14/76; 18.4%), thalamic hyperechogenicity (10/76; 13.1%), periventricular leukomalacia (PVL) (4/76; 5.2%), and congenital anomalies (8; 10.5%). Abnormal CUS findings had a statistically significant association with birth weight <2000 g, prematurity, Apgar score <7, and adverse peri-natal fetal and maternal factors (all p-values <0.05). Abnormal CUS findings had a statistically significant association with poor cry, poor activity, abnormal tone, and presence of cyanosis (all p-values <0.05).

Conclusion

In this cohort study of high-risk preterm and term infants GMH-IVH, cerebral edema, thalamic hyperechogenicity, PVL, and congenital malformations were the commonest lesions detected on CUS. Abnormal CUS findings were found to have a statistically significant association with various adverse peri-natal fetal and maternal factors.

Cranial ultrasound screening in term and late preterm neonates born by vacuum-assisted delivery: Is it worthwhile?

BACKGROUND

Vacuum extraction is the most common choice to assist vaginal delivery, but there are still concerns regarding the neonatal injuries it may cause. This study aimed to evaluate the rate of intracranial injuries assessed by cranial ultrasound (cUS) among infants born by vacuum extraction, and the relationship with maternal and perinatal factors.

METHODS

This was a single-center retrospective study carried out in a level-3 neonatal unit. A total of 593 term and late preterm infants born by vacuum-assisted delivery were examined with a cUS scan within 3 days after birth.

RESULTS

Major head injuries were clinically silent and occurred in 2% of the infants, with a rate of intracranial haemorrhage of 1.7%. Regardless of obstetric factors, the risk of cranial injury was increased in infants requiring resuscitation at birth (p = 0.04, OR 4.1), admitted to NICU (p = 0.01, OR 5.5) or with perinatal asphyxia (p < 0.01, OR 21.3). Maternal age ≥40 years correlated both with adverse perinatal outcomes (p < 0.05) and the occurrence of major injury (p = 0.02, OR 4.6).

CONCLUSION

Overall, vacuum extraction is a safe procedure for neonates. Head injuries are usually mild and asymptomatic, and with spontaneous recovery. However, the rate of major cranial injuries in our cohort warrants further investigation to support a cUS screening, particularly for infants requiring respiratory support at birth. Also, maternal age might be taken into account when evaluating the risk for neonatal complications after vacuum application.

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.

A systematic review on brain injury and altered brain development in moderate-late preterm infants

OBJECTIVES

To provide a systematic review of brain injury and altered brain development in moderate-late preterm (MLPT) infants as compared to very preterm and term infants.

STUDY DESIGN

A systematic search in five databases was performed in January 2020. Original research papers on incidence of brain injury and papers using quantitative data on brain development in MLPT infants were selected. The Johanna Briggs Institute 'Critical Appraisal Checklist for Studies Reporting Prevalence Data' was used for quality appraisal. Data extraction included: imaging modality, incidences of brain injury, brain volumes, 2D-measurements and diffusivity values.

RESULTS

In total, 24 studies were eligible. Most studies had a moderate quality. Twenty studies reported on the incidence of brain injury in MLPT infants. The incidence of intraventricular hemorrhage (IVH) ranged from 0.0% to 23.5% and of white matter injury (WMI) from 0.5% to 10.8%. One study reported the incidence of arterial infarction (0.3%) and none of cerebellar hemorrhage. Eleven studies compared incidences of brain injury between MLPT infants and very preterm or term infants. Five studies reported signs of altered brain development in MLPT infants.

CONCLUSIONS

The incidences of IVH and WMI in MLPT infants varied widely between studies. Other abnormalities were sparsely reported. Evidence regarding a higher or lower incidence of brain injury in MLPT infants compared to very preterm or term infants is weak due to moderate methodological quality of reported studies. There is limited evidence suggesting a difference in brain development between MLPT and term infants.