Spontaneous regression of an epidermoid cyst in a pediatric patient-Case report and review of the literature.

Epidermoid cysts are infrequent, benign, slow-growing, space-occupying lesions that account for 0.5-1.8% of primary intracranial tumors. We report the case of a 17-month-old child who presented in 2015 for one episode of pallor associated with hypotonia. Epilepsy was excluded and MRI was recommended. The MRI was performed and there were no focal parenchymal lesions, but it showed an extra-axial ovoid lesion with imaging characteristics consistent with epidermoid cyst. Follow-up MRI at one year was performed and it showed minimal increased in dimensions of the cyst, without changes into the signal of the lesion. Another MRI was performed 7 years after and it showed complete resolution of the cyst. Six months afterwards, another MRI was performed and it confirmed the complete regression of the cyst, without any extra-axial masses reported. The patient did not present any neurological anomalies. No follow-up MRI was recommended afterwards. Spontaneous regression of epidermoid cyst in pediatric population is an extremely rare event, but it should be taken into account when the patient shows no symptoms. This is the third case of spontaneous regression of an epidermoid cyst reported in pediatric patients, and the first one in the temporal region. Careful follow-up and watchful waiting could be an option to surgical treatment in epidermoid cysts.

Guidelines for magnetic resonance imaging in pediatric head and neck pathologies: a multicentre international consensus paper.

The use of standardized imaging protocols is paramount in order to facilitate comparable, reproducible images and, consequently, to optimize patient care. Standardized MR protocols are lacking when studying head and neck pathologies in the pediatric population. We propose an international, multicenter consensus paper focused on providing the best combination of acquisition time/technical requirements and image quality. Distinct protocols for different regions of the head and neck and, in some cases, for specific pathologies or clinical indications are recommended. This white paper is endorsed by several international scientific societies and it is the result of discussion, in consensus, among experts in pediatric head and neck imaging.

Enhancing cyst-like lesions of the white matter in tuberous sclerosis complex: a novel neuroradiological finding.

Tuberous sclerosis complex (TSC) is an autosomal dominant condition clinically presenting with heterogenous clinical features. Multiple neuroradiological manifestations have been associated with TSC, such as tubers, radial migration lines, subependymal nodules, subependymal giant cell astrocytomas, and cyst-like lesions of the white matter (CLLWMs). The latter have been described as non-enhancing well-defined cysts whose pathogenesis is still unknown. We describe 2 TSC patients with CLLWM showing contrast enhancement after Gadolinium injection, a previously unreported entity.

MRI-based diagnosis and treatment of pediatric brain tumors: is tissue sample always needed?

Traditional management of newly diagnosed pediatric brain tumors (PBTs) consists of cranial imaging, typically magnetic resonance imaging (MRI), and is frequently followed by tissue diagnosis, through either surgical biopsy or tumor resection. Therapy regimes are typically dependent on histological diagnosis. To date, many treatment regimens are based on molecular biology. The scope of this article is to discuss the role of diagnosis and further treatment of PBTs based solely on MRI features, in light of the latest treatment protocols. Typical MRI findings and indications for surgical biopsy of these lesions are described.

Pediatric neuroimaging at a university hospital in Rwanda: a pictorial essay.

Rwanda is a country of 12 million people with 41% of its population under the age of 14 years. Despite major improvements in health care since the 1994 genocide, pediatric neuroimaging in Rwanda remains challenging. Prenatal and advanced imaging techniques, such as magnetic resonance imaging (MRI), are not widespread. As a result, many children with neurological diseases present unexpectedly as newborns or are in advanced stages of disease at diagnosis. The goal of this essay is to describe some unique features of the practice of pediatric neuroradiology in Rwanda in 2018.

Imaging Stewardship: Triage for Neuroradiology MR During Limited-Resource Hours.

OBJECTIVES: To decrease call burden on pediatric neuroradiologists, we developed guidelines for appropriate use of MR overnight. These guidelines were implemented using triage by in-house generalist pediatric radiologists. Process measures and balancing measures were assessed during implementation. METHODS: For this improvement project, interdepartmental consensus guidelines were developed using exploratory mixed-methods design. Implementation of triage used plan-do-study-act cycles. Process measures included reduction in the number of telephone calls, frequency of calls, triage decisions, and number and type of examinations ordered. Balancing measures included burden of time and effort to the generalist radiologists. Differences in examination orders between implementation intervals was assessed using Kruskal-Wallis, with significance at P < .05. RESULTS: Consensus defined MR requests as "do," "defer," or "divert" (to CT). Guidelines decreased neuroradiologist calls 74% while adding minimal burden to the generalist radiologists. Most nights had zero or one triage request and the most common triage decision was "do," and the most common examination was routine brain MR. Number of MR ordered and completed overnight did not significantly change with triage. DISCUSSION: Multidisciplinary consensus for use of pediatric neurological MR during limited resource hours overnight is an example of imaging stewardship that decreased the burden of calls and burnout for neuroradiologists while maintaining a comparable level of service to the ordering clinicians.

[Congenital brain malformations]. / Angeborene Hirnfehlbildungen.

CLINICAL ISSUE: Malformations of the central nervous system belong to the most common developmental disorders in humans. The clinical presentation of brain malformations is nonspecific including developmental delay, hypotonia, and/or epilepsy. The great heterogeneity concerning etiology, mechanisms of development and morphology is challenging for diagnosis and classification of brain malformations. Thereby recognizing specific malformations is essential for optimal patient management and prognostic evaluation. The aim of this article is to give an overview of several clinically relevant brain malformations occurring from different disrupted developmental processes in brain formation. STANDARD RADIOLOGICAL METHODS: Several brain malformations are already diagnosed during routine ultrasound in pregnancy. However pre- and postnatal magnetic resonance imaging remains the gold standard in detecting the partially subtle changes and to classify the malformations. METHODICAL INNOVATIONS: Advances in pre- and postnatal neuroimaging techniques and increasing investigation of genetic mechanisms underlying brain formation and its abnormalities have led to a better understanding of embryologic development and pathogeneses of brain malformations. CONCLUSION: Besides patient's history and clinical phenotype, neuroimaging plays a key role in diagnosis. Not always a specific diagnosis can be made, but neuroimaging patterns often enable a focused genetic testing and therefore are revolutionary for etiologic and prognostic assignment. Basic knowledge of brain development facilitates understanding and classifying of structural brain abnormalities.

Novel Development of a Large Cerebral Cavernous Malformation in an Adolescent With a History of Familial Cerebral Cavernous Malformation Syndrome.

Cerebral cavernous malformations (CCM) are capillary vascular malformations of the central nervous system (CNS). These lesions can be either familial or sporadic. We present a case of a 16-year-old girl with familial CCM syndrome who presented with a six-month history of chronic headaches. A magnetic resonance imaging (MRI) scan revealed a large cavernoma in the right frontal lobe that had not been present on a prior scan performed eight years earlier. This case presentation demonstrates the possibility of significant novel cavernoma development further into adolescence.

Magnetic Resonance Imaging-Based Distribution and Reversibility of Lesions in Pediatric Vigabatrin-Related Brain Toxicity.

BACKGROUND: We aimed to systematically characterize the magnetic resonance imaging (MRI) findings in vigabatrin-related neurotoxicity in children and determine the reversibility of lesions based on follow-up images. METHODS: We evaluated children with a history of refractory seizures who had a brain MRI while on vigabatrin therapy. We included available brain MRI studies before vigabatrin therapy initiation, during vigabatrin treatment, and after vigabatrin was discontinued. A pediatric neuroradiologist systematically assessed images on T2/fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging /apparent diffusion coefficient sequences to identify hyperintense lesions and/or restricted diffusion. The frequency of abnormal signal at each location was determined, as well as the reversibility of these after vigabatrin discontinuation. RESULTS: MRIs of 43 patients were reviewed: 13 before vigabatrin initiation, 18 during treatment, and 12 after vigabatrin discontinuation. In the MRIs acquired during vigabatrin treatment, most lesions on T2/FLAIR occurred in the globus pallidi, thalami, and midbrain. Correspondingly, the most common locations for restricted diffusion were the globus pallidi, thalami, and subthalamic nuclei. On MRI after vigabatrin discontinuation, complete resolution of lesions on T2/FLAIR in all patients was seen in the midbrain, dentate nuclei, subthalamic nuclei, and hypothalami. Complete resolution of restricted diffusion was observed in the globus pallidi, midbrain, dentate nuclei, hippocampi, anterior commissure, and hypothalami. CONCLUSION: Globus pallidi and thalami are the most commonly affected structures in vigabatrin-related toxicity, and most vigabatrin-related neuroimaging findings are reversible.

Persistent falcine sinus in the newborn: 3 case reports of associated anomalies.

The falcine sinus is a normal embryonic structure that is situated between the 2 layers of the falx cerebri and drains the deep cerebral venous system into the superior sagittal sinus. It normally involutes after birth and is uncommon in adults. Although it is often an isolated and incidental finding, it can also be associated with a number of other conditions including but not limited to vein of Galen arterial malformations (VGAM), atretic parietal cephaloceles, acrocephalosyndactyly (Apert syndrome), absence of the corpus callosum, absence of the tentorium, osteogenesis imperfecta, or Chiari II malformations. We present a case series of 3 pediatric patients born with a persistent falcine sinus and an associated condition, including a VGAM, an APC, and a sinus thrombosis. The purpose of this article is to highlight the importance of understanding anatomic variations in the cerebral venous system to help aid in the proper diagnosis and treatment of associated pathologies.

Distribution of IntraThalamic Injury According to Nuclei and Vascular Territories in Children With Term Hypoxic-Ischemic Injury.

BACKGROUND: Term hypoxic-ischemic injury (HII) on magnetic resonance imaging (MRI) is described as the basal ganglia thalamus [BGT], watershed [WS], or combined [BGT/WS] groups. We aimed to determine differences between HII groups in intrathalamic distribution. METHODS: Delayed MRIs of children with HII and thalamic injury were reviewed. Custom tools were placed over T2-weighted and/or fluid-attenuated inversion recovery axial images to determine distribution of intrathalamic injury: (1) six subjective (whole/near-whole, central, anterior, posterior, lateral, medial); (2) four nuclear (anterior [AN], ventrolateral [VLN], medial [MN], and pulvinar [PN]); and (3) three arterial (thalamoperforating arteries [TPA], thalamogeniculate arteries [TGA], and posterior choroidal arteries [PCA]) locations. We compared the frequency of injury of the aforementioned intrathalamic locations between HII groups. RESULTS: The 128 children (mean age at MRI 7.35 ± 3.6 years) comprised 41% (n = 53) BGT, 26% (n = 33) WS, and 33% (n = 42) BGT/WS. The VLN was the most frequent injured nuclear region (66%, n = 85), and the TGA (93%, n = 128) was the most frequent arterial region involved. VLN injury occurred more frequently in the BGT group (P < 0.001), PN in the WS group (P < 0.001), and AN (P < 0.001), MN (P < 0.001), PN (P = 0.001), and all nuclei together (P < 0.001) in the BGT/WS group. The combination of all vascular territories was significantly associated with BGT/WS (P < 0.001). CONCLUSIONS: There are significant differences in intrathalamic nuclear and arterial injuries between the different types of HII.

Relationship Between Vesicoureteric Reflux and Nephrocalcinosis in Children: A Case-Control Study at a Tertiary Medical Center in Saudi Arabia.

BACKGROUND:  Vesicoureteral reflux (VUR), one of the most common pediatric congenital urogenital abnormalities, refers to the abnormal backflow of urine from the urinary bladder back into the ureter or to the kidney. This causes urinary tract infections. Nephrocalcinosis (NC) refers to abnormal deposits of calcium within the renal parenchyma and/or in the renal cortex. Patients with NC are mostly asymptomatic and severe disease may progress to renal failure. Early diagnosis through examinations such as radiography, computed tomography, and ultrasonography, is crucial for therapeutic treatment. Ultrasonography is the preferred method for scanning and grading nephrocalcinosis in children, primarily because it emits no radiation. This study aimed to increase the body of knowledge regarding VUR and nephrocalcinosis by determining its prevalence and assessing the relationship between VUR and nephrocalcinosis in children presenting at our institution. ​​​​Methods:A case-control study was conducted using data from the medical records of 632 children younger than 14 years in a tertiary medical center in Riyadh, Saudi Arabia. Eligible participants were assigned to two groups: Group 1 consisted of 316 patients with VUR, while Group 2 consisted of 316 sex- and age-matched patients without VUR. The difference in the prevalence of nephrocalcinosis between the two groups was assessed. Frequency and percentage were used to present the categorical variables; Pearson product-moment correlation was utilized to establish the association between VUR and nephrocalcinosis. Statistical significance was established at p<0.05. ​​​​​Result: Only two cases in Group 1 were positive for nephrocalcinosis (0.63%, one male and one female), while four cases in Group 2 were positive for the condition (1.26%, two males and two females). There was no significant difference in the incidence of nephrocalcinosis between the two groups (p=0.873), indicating no relationship between VUR and nephrocalcinosis in children. CONCLUSION: There is no relationship between VUR and nephrocalcinosis in children under the age of 14 years.

Utility of Cerebral Microvascular Imaging in Infants Undergoing ECMO.

PURPOSE: Infants who require extracorporeal membrane oxygenation (ECMO) therapy have an increased risk of neurological complications and mortality. Microvascular imaging (MVI) is an advanced Doppler technique that allows high-resolution visualization of microvasculature in the brain. We describe the feasibility and utility of MVI for the evaluation of cerebral microvascular perfusion in patients undergoing ECMO. METHODS: We retrospectively analyzed brain MVI scans of neonates undergoing ECMO. Two pediatric radiologists qualitatively assessed MVI scans to determine the presence or absence of tortuosity, symmetry, heterogeneity, engorgement, and hypoperfusion of the basal ganglia-thalamus (BGT) region, as well as the presence or absence of white matter vascular engorgement and increased peri-gyral flow in the cortex. We tested the association between the presence of the aforementioned brain MVI features and clinical outcomes. RESULTS: We included 30 patients, 14 of which were male (46.7%). The time of ECMO duration was 11.8 ± 6.9 days. The most prevalent microvascular finding in BGT was lenticulostriate vessel tortuosity (26/30, 86.7%), and the most common microvascular finding in the cortex was increased peri-gyral flow (10/24, 41.7%). Cortical white matter vascular engorgement was significantly associated with the presence of any poor outcome as defined by death, seizure, and/or cerebrovascular events on magnetic resonance imaging (p = 0.03). CONCLUSION: MVI is a feasible modality to evaluate cerebral perfusion in infants undergoing ECMO. Additionally, evidence of white matter vascular engorgement after ECMO cannulation could serve as a predictor of poor outcomes in this population.

Characterization of pediatric brain tumors using pre-diagnostic neuroimaging.

Purpose: To evaluate for predictive neuroimaging features of pediatric brain tumor development and quantify tumor growth characteristics in patients who had neuroimaging performed prior to a diagnosis of a brain tumor. Methods: Retrospective review of 1098 consecutive pediatric patients at a single institution with newly diagnosed brain tumors from January 2009 to October 2021 was performed to identify patients with neuroimaging prior to the diagnosis of a brain tumor. Pre-diagnostic and diagnostic neuroimaging features (e.g., tumor size, apparent diffusion coefficient (ADC) values), clinical presentations, and neuropathology were recorded in those patients who had neuroimaging performed prior to a brain tumor diagnosis. High- and low-grade tumor sizes were fit to linear and exponential growth regression models. Results: Fourteen of 1098 patients (1%) had neuroimaging prior to diagnosis of a brain tumor (8 females, mean age at definitive diagnosis 8.1 years, imaging interval 0.2-8.7 years). Tumor types included low-grade glioma (n = 4), embryonal tumors (n = 2), pineal tumors (n=2), ependymoma (n = 3), and others (n = 3). Pre-diagnostic imaging of corresponding tumor growth sites were abnormal in four cases (28%) and demonstrated higher ADC values in the region of high-grade tumor growth (p = 0.05). Growth regression analyses demonstrated R2-values of 0.92 and 0.91 using a linear model and 0.64 and 0.89 using an exponential model for high- and low-grade tumors, respectively; estimated minimum velocity of diameter expansion was 2.4 cm/year for high-grade and 0.4 cm/year for low-grade tumors. High-grade tumors demonstrated faster growth rate of diameter and solid tumor volume compared to low-grade tumors (p = 0.02, p = 0.03, respectively). Conclusions: This is the first study to test feasibility in utilizing pre-diagnostic neuroimaging to demonstrate that linear and exponential growth rate models can be used to estimate pediatric brain tumor growth velocity and should be validated in a larger multi-institutional cohort.

COVID-19 related vascular complications in a pediatric patient: A case report.

The novel coronavirus infection (COVID-19) caused by the SARS-CoV-2 virus is a relatively recent infection that has resulted in a global pandemic, appearing first at the end of 2019. While initially presenting as a predominantly respiratory disease, with a classical picture of fever, dry cough, dyspnea and, in some cases anosmia and ageusia, recent cases have shown increasingly atypical and more systemic manifestation of the disease. A precise understanding of the extent and pathophysiology of COVID-19 remains underway to this day, particularly concerning its behavior in the pediatric population. Moreover, there has been an increasing number of COVID-19 reports with neurological complications and manifestations, prompting inquiry into neuroinvasion. Postulations include indirect invasion through a surge of inflammatory mediators "cytokine storm" and subsequent widespread endothelial injury; and direct neural tropism. We report the case of a previously healthy 12-year-old male presenting with acute right-sided hemiparesis, new-onset seizures and a generalized petechial rash. Laboratory tests revealed elevated inflammatory markers and radiological investigations confirmed an evolving left middle cerebral artery (MCA) infarct and large vessel vasculitis. Testing for SARS-CoV-2 infection was positive.

Current Perspectives of Artificial Intelligence in Pediatric Neuroradiology: An Overview.

Artificial Intelligence, Machine Learning, and myriad related techniques are becoming ever more commonplace throughout industry and society, and radiology is by no means an exception. It is essential for every radiologists of every subspecialty to gain familiarity and confidence with these techniques as they become increasingly incorporated into the routine practice in both academic and private practice settings. In this article, we provide a brief review of several definitions and techniques that are commonly used in AI, and in particular machine vision, and examples of how they are currently being applied to the setting of clinical neuroradiology. We then review the unique challenges that the adoption and application of faces within the subspecialty of pediatric neuroradiology, and how these obstacles may be overcome. We conclude by presenting specific examples of how AI is currently being applied within the field of pediatric neuroradiology and the potential opportunities that are available for future applications.

MRI imaging of prenatal-postatal brain malformations.

A fetus with suspicion for holoprosencephaly and various brain malformations were seen on ultrasound and send for magnetic resonance imaging (MRI). Immediately after the birth of the female patient ultrasound and MRI was made which confirmed lobar holoprosencephaly. Fetal MRI stands out as a powerful diagnostic tool for detecting anomalies and other disorders. By developing new sequences and raising image quality will enable visualization of small details.

MR Imaging of Normal Brain Development.

Normal brain development is best evaluated by MR imaging in the fetal and pediatric patient. As the developing brain grows, myelinates, and sulcates rapidly, understanding the normal appearance of the brain throughout development is critical. The fetal brain can be evaluated by MR imaging after 16 weeks gestational age, both morphologically and biometrically. Sulcation of the fetal brain lags behind premature neonates of equivalent gestational age. Sensory axons generally myelinate before motor axons with central to peripheral and dorsal to ventral myelination gradients. By 2 years of age, the brain has a near adult appearance by conventional anatomic MR imaging.

Adams-Oliver Syndrome with Unusual Central Nervous System Findings and an Extrahepatic Portosystemic Shunt.

We report a case of a premature neonate girl with scalp and skull defects and brachydactyly of the feet consistent with an Adams-Oliver syndrome (AOS). The patient had central nervous system abnormalities, such as periventricular calcifications, hypoplastic corpus callosum, and bilateral hemispheric corticosubcortical hemorrhagic lesions. A muscular ventricular septal defect and a portosystemic shunt were diagnosed. To our knowledge, this is the first report of congenital supratentorial grey-white matter junction lesions without dural sinus thrombosis in association with AOS. Some of these lesions may be secondary to birth trauma (given the skull defect) whilst others have a watershed location, perhaps as further evidence of vascular disruption and decreased perfusion during critical periods of fetal brain development as the previously proposed pathogenesis of this syndrome.

A case of Jacobsen syndrome with multifocal white matter lesions.

Jacobsen syndrome is a rare disorder caused by partial deletions of the long arm of chromosome 11. The phenotype is variable with involvement of multiple organ systems, resulting in congenital heart defects, blood dyscrasias, and impaired growth. We describe a case of a 30-year-old man with multiple ophthalmic manifestations and brain magnetic resonance imaging (MRI) that was remarkable for multiple T2-hyperintense subcortical white matter lesions. It is important to be aware that patients with Jacobsen syndrome may have nonspecific white changes seen on MRI.