Hypoxic-ischemic brain damage presents a significant neurological challenge, often manifesting during the perinatal period. Specifically, periventricular leukomalacia (PVL) is emerging as a notable contributor to cerebral palsy and intellectual disabilities. It compromises cerebral microcirculation, resulting in insufficient oxygen or blood flow to the periventricular region of the brain. As widely documented, these pathological conditions can be caused by several factors encompassing preterm birth (4-5% of the total cases), as well single cotwin abortion and genetic variants such as those associated with GTPase pathways. Whole exome sequencing (WES) analysis identified a de novo causative variant within the pleckstrin homology domain-containing family G member 1 (PLEKHG1) gene in a patient presenting with PVL. The PLEKHG1 gene is ubiquitously expressed, showing high expression patterns in brain tissues. PLEKHG1 is part of a family of Rho guanine nucleotide exchange factors, and the protein is essential for cell division control protein 42 (CDC42) activation in the GTPase pathway. CDC42 is a key small GTPase of the Rho-subfamily, regulating various cellular functions such as cell morphology, migration, endocytosis, and cell cycle progression. The molecular mechanism involving PLEKHG1 and CDC42 has an intriguing role in the reorientation of cells in the vascular endothelium, thus suggesting that disruption responses to mechanical stress in endothelial cells may be involved in the formation of white matter lesions. Significantly, CDC42 association with white matter abnormalities is underscored by its MIM phenotype number. In contrast, although PLEKHG1 has been recently associated with patients showing white matter hyperintensities, it currently lacks a MIM phenotype number. Additionally, in silico analyses classified the identified variant as pathogenic. Although the patient was born prematurely and subsequently to dichorionic gestation, during which its cotwin died, we suggest that the variant described can strongly contribute to PVL. The aim of the current study is to establish a plausible association between the PLEKHG1 gene and PVL.

OBJECTIVE: Intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL) in preterm infants are associated with an increased risk of long-term neurodevelopmental impairments (NDI) and cerebral palsy (CP). However, little is known about their impact on early neurodevelopmental outcomes despite increasing evidence highlighting the feasibility and importance of early NDI/CP diagnosis. We aimed to determine the early neurodevelopmental outcomes of preterm infants with IVH and PVL.
METHODS: This was a retrospective single-centre cohort study of preterm infants born at <29 weeks gestation or <1000 g birth weight who attended an Early Neurodevelopment Clinic at 3 to 4 months of corrected age. Primary outcomes of early NDI and CP/high-risk CP diagnoses based on Prechtl\'s General Movements Assessment and the Hammersmith Infant Neurological Examination were compared between infants without IVH and infants with mild IVH (grades I-II), severe IVH (grades III-IV), and severe brain injury (SBI; severe IVH or cystic PVL).
RESULTS: Of 313 infants, 52.1% (n = 163), 41.2% (n = 129), 6.7% (n = 21) and 8.6% (n = 27) had no IVH, mild IVH, severe IVH and SBI, respectively. The adjusted odds of early CP/high-risk CP diagnosis were significantly higher in infants with severe IVH (aOR 6.07, 95% CI 1.50-24.50) and SBI (aOR 15.28, 95% CI 3.70-63), but not in those with mild IVH (aOR 1.24, 95% CI 0.49-3.10). However, the adjusted odds of any early NDI were similar across groups.
CONCLUSIONS: Preterm infants with severe IVH and SBI are at increased risk of early CP/high-risk of CP diagnosis at 3 to 4 months of corrected age.

Cerebral palsy is a disorder characterized by abnormal tone, posture, and movement. In clinical practice, it is often useful to approach cerebral palsy based on the predominant motor system findings - spastic hemiplegia, spastic diplegia, spastic quadriplegia, extrapyramidal or dyskinetic, and ataxic. The prevalence of cerebral palsy is between 1.5 and 3 per 1,000 live births with higher percentage of cases in low to middle income countries and geographic regions. Pre-term birth and low birthweight are recognized as the most frequent risk factors for cerebral palsy; other risk factors include hypoxic-ischemic encephalopathy, maternal infections, and multiple gestation. In most cases of cerebral palsy, the initial injury to the brain occurs during early fetal brain development. Intracerebral hemorrhage and periventricular leukomalacia are the main pathologic findings found in preterm infants who develop spastic cerebral palsy. The diagnosis of cerebral palsy is primarily based on clinical findings. Early recognition of infants at risk for cerebral palsy as well as those with cerebral palsy is possible based on a combination of clinical history, use of standardized neuromotor assessment and findings on magnetic resonance imaging; however, in clinical practice, cerebral palsy is more reliably diagnosed by 2 years of age. Magnetic resonance imaging scan is indicated to delineate the extent of brain lesions and to identify congenital brain malformations. Genetic testing and tests for inborn errors of metabolism are indicated to identify specific disorders, especially treatable disorders. Because cerebral palsy is associated with multiple associated and secondary medical conditions, its management requires a sustained and consistent collaboration among multiple disciplines and specialties. With appropriate support, most children with cerebral palsy grow up to be adults with good functional abilities.

UNASSIGNED: Congenital heart disease (CHD) is the most common birth defect, affecting 1% of children who are born in the United States each year. Children with hypoplastic left heart syndrome, a type of critical CHD, are at high risk for neurodevelopmental disabilities, which are conditions that can affect motor, language, and cognitive development. In children with critical CHD, the severity and prevalence of their motor delays is most pronounced in infancy.
UNASSIGNED: We present a case of a former late preterm male with hypoplastic left heart syndrome and history of hypoxic ischemic encephalopathy, who was diagnosed with spastic diplegic cerebral palsy in the setting of periventricular leukomalacia. Like many children with critical CHD, this child had gross motor delays and tone abnormalities in infancy. However, unlike many children with CHD, he continued to have neurologic differences that prompted additional evaluation through a Cardiac Neurodevelopmental Program. He was diagnosed with spastic diplegic cerebral palsy based upon clinical history and physical examination. Ancillary testing showed periventricular leukomalacia on brain magnetic resonance imaging (MRI); this finding was consistent with his clinical diagnosis.
UNASSIGNED: This is an interesting case report of spastic diplegic cerebral palsy in a late preterm infant with critical CHD. When making a diagnosis of cerebral palsy, it is important to consider the etiology of the motor impairment. Selective vulnerability may have played a factor in this child\'s condition. The most vulnerable part of the neonatal brain is the periventricular white matter; cerebral hypoxia can lead to periventricular leukomalacia. Children with CHD have brain dysmaturity beginning in-utero. Thus, it is possible that this child\'s brain dysmaturity may have increased his susceptibility to periventricular leukomalacia. Because most children with CHD have gross motor delays in infancy, it may be challenging to make a definitive diagnosis of cerebral palsy in an infant with critical CHD. Children with cerebral palsy have early motor delays that persist throughout life. It is the identification of persistent motor impairments through repeat evaluations that enabled this child\'s cerebral palsy diagnosis. This illustrates the importance of developmental surveillance in children with critical CHD.

Intrapartum fetal heart rate monitoring abnormalities had been reported to correlate with decreased umbilical artery base excess associated with neonatal seizures. However, we present an infant born at 35 weeks of gestation diagnosed with cerebral palsy associated with periventricular leukomalacia (PVL) without fetal heart rate (FHR) monitoring abnormalities, According to the summary reports of PVL cases published on the home page of the Japan Obstetric Compensation System for Cerebral Palsy (JOCSC)), the percentage of placenta previa without FHR monitoring abnormalities in the cases of PVL was 5.7% (12/209), which seemed to be higher than the total percentage of placenta previa reported in Japan (0.3-0.5%).

Holoprosencephaly (HPE) is a classic brain malformation involving defective forebrain induction and patterning. Cases of HPE bearing white matter abnormalities have not been well documented, with only rare cases exhibiting hypoxic-ischemic damage. However, neuroradiologic studies of HPE using diffusion tensor imaging have suggested the presence of white matter architectural disarray. Described in this case series are the clinicopathologic features of 8 fetuses with HPE who underwent autopsy at BC Children\'s Hospital. All 8 cases exhibited subacute to chronic, periventricular leukomalacia (PVL)-like white matter pathology, with 7 of 8 cases also demonstrating aberrant white matter tracts, one of which manifested as a discreet bundle crossing the midline within the ventral aspects of the fused deep gray nuclei. In 6 of these 7 cases, the PVL-like pathology resided within this aberrant white matter tract. Original workup, alongside an additional HPE-focused next-generation sequencing panel identified a likely etiologic cause for the HPE in 4 cases, with an additional 2 cases exhibiting a variant of unknown significance in genes previously suggested to be involved in HPE. Despite our in-depth clinicopathologic and molecular review, no unifying etiology was definitively identified among our series of fetal HPE bearing this unusual pattern of white matter pathology.

BACKGROUND: The thalamus L-sign, characterized by damage to the lateral and posterior parts of the thalamus, has recently been identified as a potential marker of partial prolonged hypoxic-ischemic injury (HII). Although prematurity-related thalamic injury is well documented, its association with the thalamus L-sign is infrequently described.
OBJECTIVE: The primary objective of this study was to further investigate the thalamus L-sign in premature birth and white matter injury.
METHODS: A retrospective analysis of 246 brain magnetic resonance imaging (MRI) scans from preterm infants born before 37 weeks of gestation was conducted to explore the occurrence, characteristics, and associations of the thalamus L-sign with white matter injury.
RESULTS: The L-sign was detected in 12.6% of patients with periventricular leukomalacia (PVL), primarily in severe cases (57.9% of severe PVL). All cases were associated with posterior parieto-occipital PVL. Four patients exhibited unilateral or asymmetric L-signs, which were linked to high-grade intraventricular hemorrhage (IVH) or periventricular hemorrhagic infarction on the ipsilateral side, with the most severe white matter injury occurring on that side. No significant differences were observed regarding gestational age at birth, duration of neonatal intensive care unit hospitalization, percentage of IVH, hypoglycemia, or jaundice between patients with moderate-to-severe PVL with and without the thalamus L-sign.
CONCLUSIONS: The thalamus L-sign may serve as a marker for severe parieto-occipital PVL and may be exacerbated and appear asymmetric in cases of ipsilateral IVH or periventricular hemorrhagic infarction.

Pontocerebellar hypoplasia type 9 (PCH9) is a rare, autosomal, recessive, neurodevelopmental disorder caused by a mutation in the AMPD2 gene. Despite its rarity, it presents distinctive clinical and neuroradiological features. Diagnosing it is challenging yet crucial for appropriate management. We describe a 21-month-old boy with clinical and neuroradiological manifestations of the diagnosis, including characteristic signs such as an eight-configured midbrain and hypoplasia of the brainstem and cerebellar structures. Genetic evaluation confirmed homozygous missense mutations in the AMPD2 gene. This case highlights the pathognomonic neuroradiological features of pontocerebellar hypoplasia type 9 that point toward diagnosis.

Neonatal brain injury (NBI) is a critical condition for preterm neonates with potential long-term adverse neurodevelopmental outcomes. This prospective longitudinal case-control study aimed at investigating the levels and prognostic value of serum neuron-specific enolase (NSE) during the first 3 days of life in preterm neonates (<34 weeks) that later developed brain injury in the form of either periventricular leukomalacia (PVL) or intraventricular hemorrhage (IVH) during their hospitalization. Participants were recruited from one neonatal intensive care unit, and on the basis of birth weight and gestational age, we matched each case (n = 29) with a neonate who had a normal head ultrasound scan (n = 29). We report that serum NSE levels during the first three days of life do not differ significantly between control and preterm neonates with NBI. Nevertheless, subgroup analysis revealed that neonates with IVH had significantly higher concentrations of serum NSE in comparison to controls and neonates with PVL on the third day of life (p = 0.014 and p = 0.033, respectively). The same pattern on the levels of NSE on the third day of life was also observed between (a) neonates with IVH and all other neonates (PVL and control; p = 0.003), (b) neonates with II-IV degree IVH and all other neonates (p = 0.003), and (c) between control and the five (n = 5) neonates that died from the case group (p = 0.023). We conclude that NSE could be an effective and useful biomarker on the third day of life for the identification of preterm neonates at high risk of developing severe forms of IVH.

UNASSIGNED: Weaver syndrome (WS) is a rare autosomal dominant disorder characterized by distinctive facial features, pre- and post-natal overgrowth, macrocephaly, and variable developmental delay. The characteristic facial features are ocular hypertelorism, a broad forehead, almond-shaped palpebral fissures and, in early childhood, large, fleshy ears, a pointed \"stuck-on\" chin with horizontal skin creases, and retrognathia. Heterozygous pathogenic/likely pathogenic variants in the enhancer of zeste homolog 2 (EZH2) gene are responsible for WS.
UNASSIGNED: Here, we report a male patient with a heterozygous likely pathogenic variant in EZH2 gene who has tall stature, distinctive facial features, mild development delay, hypoxic-ischemic encephalopathy with a MRI finding of periventricular leukomalacia, gingival hypertrophy, and early onset high hypermetropia.
UNASSIGNED: This case demonstrates the importance of reporting detailed molecular and clinical findings in patients to expand the genotypic and phenotypic findings of this rare syndrome.