Imaging diagnosis of ventriculomegaly: fetal, neonatal, and pediatric

New reference nomograms for the study of ventricular size in preterm infants

INTRODUCTION

Transfontanellar brain ultrasound is an essential tool for monitoring the size of the ventricles in preterm neonates and has many advantages over other alternative diagnostic techniques, including its accessibility and non-use of ionizing radiation. When considering the normal ventricular size, it is essential to have reference measurements based on age-matched populations. The objective of this article is to present our reference measures, based on a sample of preterm infants that we have studied.

METHODS

A retrospective observational study was conducted. Measurements of the Levene index, frontal horn thickness, and Evans index were obtained in preterm neonates from 25 to 45 weeks, over a period of 5 years, between January 2016 and December 2020. After applying the exclusion criteria, a sample of 199 patients and 350 ultrasound scans were obtained. The independent samples t-test and the Mann-Whitney test were used for the comparison of samples.

RESULTS

The distribution of the right and left Levene indices was normal (Shapiro-Wilk test with p = 0.16 and 0.05, respectively), unlike the thickness distribution of the frontal horns (p < 0.05 on both sides). No significant differences were detected between the sexes (p = 0.08). A linear correlation was found between the biparietal diameter and the Levene index.

CONCLUSION

From the results obtained in our study, we present reference tables for ventricular size, with the 3rd, 25th, 50th, 75th, and 97th, being the first ones made in our country.

Prognostic Significance of Central Skull Base Remodeling in Chiari II Malformation

BACKGROUND AND PURPOSE

Outward convexity of the basiocciput and posterior atlanto-occipital membrane are common in patients with Chiari II malformation associated with an open neural tube defect. We aimed to determine if the severity of these findings correlated with the need for future hydrocephalus treatment.

MATERIALS AND METHODS

A retrospective chart and imaging review identified patients who underwent open neural tube defect repair at a quaternary care pediatric hospital from July 2014 through September 2022. Patients were classified by the need for hydrocephalus treatment and whether they received prenatal or postnatal neural tube defect repair. Measurements of imaging parameters related to posterior fossa maldevelopment and skull base remodeling were performed.

RESULTS

Compared with 65 patients who did not require hydrocephalus treatment, 74 patients who required treatment demonstrated statistically significantly greater mean basiocciput convexity (P < .001). While the mean basiocciput length in the hydrocephalus treatment group was smaller (P < .001), the ratio of basiocciput convexity to length was larger (P < .001). Notably, 100% of patients with a basiocciput convexity of ≥4 mm required hydrocephalus treatment. The mean posterior atlanto-occipital membrane convexity was significantly greater for patients who required hydrocephalus treatment in the postnatal group (P = .02), but not the prenatal group (P = .09).

CONCLUSIONS

Pediatric patients with Chiari II malformation who ultimately required surgical hydrocephalus treatment had greater outward convexity of the basiocciput but had greater posterior atlanto-occipital membrane outward convexity only if the repair was performed postnatally. Together these measurements may be useful in predicting the need for hydrocephalus treatment.

Magnetic Resonance Imaging Findings and Genetic Testing Results in Children With Congenital Corneal Opacities

PURPOSE

This study investigates brain and globe abnormalities identified on magnetic resonance imaging (MRI) in children with congenital corneal opacities (CCO).

DESIGN

Retrospective cohort study.

METHODS

Clinical notes, radiology records, and genetic testing results were reviewed for patients diagnosed with corneal opacification within the first 6 months of life at a tertiary referral academic center between August 2008 and January 2018. Ocular findings, systemic anomalies, neuroimaging, and genetic testing results were summarized.

RESULTS

A total of 135 patients presenting at age 1 day to 12 years (mean age, 1 year) were identified. Children with bilateral CCO were more likely to have systemic disease (P = 0.018). Of the entire cohort, 43 (31.8%) patients received MRI, of whom 27 (62.8%) had abnormal brain findings and 30 (69.7%) had abnormal orbital findings. The most common abnormal brain findings were ventriculomegaly (n = 16, 59.2%) and corpus callosum abnormalities (n = 10, 37.0%) followed by brainstem/pons anomalies (n = 5, 18.5%), and cerebellar anomalies (n = 2, 7.4%). Abnormal brain MRI findings were associated with the presence of neurologic (P = .003) and craniofacial (P = .034) disease. A total of 44 (32.1%) patients underwent genetic testing, of whom 29 (65.9%) had pathogenic results.

CONCLUSIONS

More than 60% of the children with CCO who underwent MRI had abnormal brain and orbit findings that were correlated with significant neurologic disease. Furthermore, almost two-thirds of patients with CCO who underwent genetic testing had pathogenic results. These data demonstrate the value of systemic workup in children with CCO, and highlight the role of ophthalmologists in facilitating the diagnosis of systemic comorbidities associated with CCO.

Pediatric Cerebral Venous Sinus Thrombosis: A Case Report

Cerebral venous sinus thrombosis (CVST) in infants is a rare vascular disorder that presents with nonspecific symptoms leading to a delay in diagnosis and treatment. Thrombus formation in the cerebral sinuses prevents blood from draining out of the brain leading to local and systemic complications. Here, we present an 11-week-old patient who presented to the emergency department (ED) with three days of lethargy, multiple episodes of projectile emesis, increased fussiness, and downward gaze. A CT scan demonstrated intraventricular hemorrhage (IVH) with acute hydrocephalus. A CT venogram of the cranial vault with contrast showed a large intraluminal thrombus occupying the right transverse sinus and torcula with proximal extension into the left transverse sinus confirming the diagnosis of CVST.

Perinatal Management of Pregnancies with Fetal Congenital Anomalies: A Guide to Obstetricians and Pediatricians

BACKGROUND

Congenital anomalies are responsible for approximately 20% of all neonatal deaths worldwide. Improvements in antenatal screening and diagnosis have significantly improved the prenatal detection of birth defects; however, these improvements have not translated into the improved neonatal prognosis of babies born with congenital anomalies.

OBJECTIVES

An attempt has been made to summarise the prenatal interventions, if available, the optimal route, mode and time of delivery and discuss the minimum delivery room preparations that should be made if expecting to deliver a fetus with a congenital anomaly.

METHODS

The recent literature related to the perinatal management of the fetus with prenatally detected common congenital anomalies was searched in English peer-reviewed journals from the PubMed database to work out an evidence-based approach for their management.

RESULTS

Fetuses with prenatally detected congenital anomalies should be delivered at a tertiary care centre with facilities for neonatal surgery and paediatric intensive care if needed. There is no indication for preterm delivery in the majority of cases. Only a few congenital malformations, like highrisk sacrococcygeal teratoma, congenital lung masses with significant fetal compromise, fetal cerebral lesions or neural tube defects with Head circumference >40 cm or the biparietal diameter is ≥12 cm, gastroschisis with extracorporeal liver, or giant omphaloceles in the fetus warrant caesarean section as the primary mode of delivery.

CONCLUSION

The prognosis of a fetus with congenital anomalies can be significantly improved if planning for delivery, including the place and time of delivery, is done optimally. A multidisciplinary team should be available for the fetus to optimize conditions right from when it is born.

Congenital Brain Malformations: An Integrated Diagnostic Approach

Congenital brain malformations are abnormalities present at birth that can result from developmental disruptions at various embryonic or fetal stages. The clinical presentation is nonspecific and can include developmental delay, hypotonia, and/or epilepsy. An informed combination of imaging and genetic testing enables early and accurate diagnosis and management planning. In this article, we provide a streamlined approach to radiologic phenotyping and genetic evaluation of brain malformations. We will review the clinical workflow for brain imaging and genetic testing with up-to-date ontologies and literature references. The organization of this article introduces a streamlined approach for imaging-based etiologic classification into malformative, destructive, and migrational abnormalities. Specific radiologic ontologies are then discussed in detail, with correlation of key neuroimaging features to embryology and molecular pathogenesis.

Value of pre- and postnatal magnetic resonance imaging in the evaluation of congenital central nervous system anomalies

Fetal MRI and neonatal MRI of the central nervous system (CNS) are complementary tools that can help to accurately counsel and direct the management of children with anomalies of the central nervous system. Postnatal MRI can add to fetal MRI by allowing for monitoring of changes in the severity of disease, better delineation of a suspected prenatal anomaly, evaluation for secondary pathologies related to the primary diagnosis, and surgical management direction. In this review we discuss the roles of fetal and neonatal MRI in the diagnosis and treatment of congenital anomalies of the CNS through a series of case examples and how both are important in patient management.

Clinical Applications of Fetal MRI in the Brain

Fetal magnetic resonance imaging (MRI) has become a widely used tool in clinical practice, providing increased accuracy in prenatal diagnoses of congenital abnormalities of the brain, allowing for more accurate prenatal counseling, optimization of perinatal management, and in some cases fetal intervention. In this article, a brief description of how fetal ultrasound (US) and fetal MRI are used in clinical practice will be followed by an overview of the most common reasons for referral for fetal MRI of the brain, including ventriculomegaly, absence of the cavum septi pellucidi (CSP) and posterior fossa anomalies.

Prenatal Evaluation of Intracranial Hemorrhage on Fetal MRI: A Retrospective Review

BACKGROUND AND PURPOSE

The evaluation and characterization of germinal matrix hemorrhages have been predominantly described on postnatal head sonography in premature neonates. However, germinal matrix hemorrhages that are seen in premature neonates can be also seen in fetuses of the same postconceptual age and are now more frequently encountered in the era of fetal MR imaging. Our aim was to examine and describe the MR imaging findings of fetuses with intracranial hemorrhage.

MATERIALS AND METHODS

A retrospective review of diagnostic-quality fetal MRIs showing intracranial hemorrhage from January 2004 to May 2020 was performed. Images were reviewed by 2 radiologists, and imaging characteristics of fetal intracranial hemorrhages were documented. Corresponding postnatal imaging and clinical parameters were reviewed.

RESULTS

One hundred seventy-seven fetuses with a mean gestational age of 25.73 (SD, 5.01) weeks were included. Germinal matrix hemorrhage was identified in 60.5% (107/177) and nongerminal matrix hemorrhage in 39.5% (70/177) of patients. Significantly increased ventricular size correlated with higher germinal matrix hemorrhage grade (P < .001). Fetal growth restriction was present in 21.3% (20/94) of our population, and there was no significant correlation with germinal matrix grade or type of intracranial hemorrhage. An increased incidence of neonatal death with grade III germinal matrix hemorrhages (P = .069) compared with other grades was identified; 23.2% (16/69) of the neonates required ventriculoperitoneal shunts, with an increased incidence in the nongerminal matrix hemorrhage group (P = .026).

CONCLUSIONS

MR imaging has become a key tool in the diagnosis and characterization of intracranial hemorrhage in the fetus. Appropriate characterization is important for optimizing work-up, therapeutic approach, and prenatal counseling.

TrkA mediates effect of novel KIDINS220 mutation in human brain ventriculomegaly

Congenital hydrocephalus is a potentially devastating, highly heterogeneous condition whose genetic subset remains incompletely known. We here report a consanguineous family where three fetuses presented with brain ventriculomegaly and limb contractures and shared a very rare homozygous variant of KIDINS220, consisting of an in-frame deletion of three amino acids adjacent to the fourth transmembrane domain. Fetal brain imaging and autopsy showed major ventriculomegaly, reduced brain mass, and with no histomorphologic abnormalities. We demonstrate that the binding of KIDINS220 to TrkA is diminished by the deletion mutation. This family is the second that associates a KIDINS220 genetic variant with human ventriculomegaly and limb contractures, validating causality of the gene and indicating TrkA as a likely mediator of the phenotype.