Felice D'Arco

Great Ormond Street Hospital for Children NHS Foundation Trust | GOSH · Department of Radiology

We describe a set of monozygotic twins with GRIN2B-related neurodevelopmental disorder (GRIN2B-ND) who exhibited distinct clinical and imaging characteristics due to a de novo heterozygous pathogenic variant in the GRIN2B gene (c.2453T>C, p.Met818Thr). Twin A displayed extensive symmetric malformation of cortical development (MCD) resembling polymi...

Objective: Hippocampal sclerosis (HS), the most common pathology associated with temporal lobe epilepsy (TLE), is not always visible on magnetic resonance imaging (MRI), causing surgical delays and reduced postsurgical seizure-freedom. We developed an open-source software to characterize and localize HS to aid the presurgical evaluation of childre...

An increasing number of individuals with intellectual developmental disorder (IDD) and heterozygous variants in BCL11A are identified, yet our knowledge of manifestations and mutational spectrum is lacking. To address this, we performed detailed analysis of 42 individuals with BCL11A -related IDD (BCL11A-IDD, a.k.a. Dias-Logan syndrome) ascertained...

Background Malformations of cortical development (MCDs) in children with focal epilepsy pose significant diagnostic challenges, and a precise radiological diagnosis is crucial for surgical planning. New MRI sequences and the use of artificial intelligence (AI) algorithms are considered very promising in this regard, yet studies evaluating the relat...

Background and purpose: Cerebellar heterotopia (CH) is a neuroradiologic abnormality that is poorly reported and investigated in the literature. It can be observed as an isolated finding, but it has been mainly reported in the context of cerebellar dysgenesis and syndromic conditions. This study aims to provide a comprehensive neuroradiologic, cli...

Background and purpose: Duplication of the pituitary gland is a rare developmental anomaly. Multiple associated craniofacial malformations have previously been reported with the largest series to date consisting of five patients. In this multi-institutional series of ten patients, we present a detailed review of the imaging features and discuss a...

Purpose Normative ADC values of the pineal gland in young children are currently lacking, however, these are potentially useful in the differential diagnosis of pineal involvement in trilateral retinoblastoma, which is challenging when the size of the tumor is less than 10–15 mm. The main objective of this study was to establish ADC reference value...

Purpose Low-field (LF) MRI scanners are common in many Low- and middle-Income countries, but they provide images with worse spatial resolution and contrast than high-field (HF) scanners. Image Quality Transfer (IQT) is a machine learning framework to enhance images based on high-quality references that has recently adapted to LF MRI. In this study...

Cortically based brain tumors in children constitute a unique set of tumors with variably aggressive biologic behavior. Because radiologists play an integral role on the multidisciplinary medical team, a clinically useful and easy-to-follow flow chart for the differential diagnoses of these complex brain tumors is essential. This proposed algorithm...

Background and objective Foramen magnum stenosis (FMS) is a common, serious complication of achondroplasia in infancy and associated with sudden infant death. The Achondroplasia Foramen Magnum Score (AFMS; 0–4) is used to classify the severity of stenosis to inform appropriate neurosurgical management. Infants with AFMS4 are referred for neurosurge...

Background and purpose: Sotos syndrome is a rare autosomal dominant condition caused by pathogenic mutations in the NSD1 gene that presents with craniofacial dysmorphism, overgrowth, seizures, and neurodevelopmental delay. Macrocephaly, ventriculomegaly, and corpus callosal dysmorphism are typical neuroimaging features that have been described in...

Background Central nervous system (CNS) cancers are a leading cause of childhood cancer-related mortality. Accurate staging and assessment of leptomeningeal spread, particularly in aggressive neoplasms like embryonal tumors, is crucial for treatment planning and prognosis. Conventional diagnostic methods, relying on MRI and CSF cytology, have limit...

Background and purpose: Neuronal ceroid lipofuscinoses (NCL) are a group of neurodegenerative disorders. Recently, enzyme replacement therapy (ERT) was approved for CLN2, a subtype of NCL. The aim of this study was to quantify brain volume loss in CLN2 disease of patients on ERT in comparison to a natural history cohort using magnetic resonance im...

Haemolytic Uraemic Syndrome (HUS) is a rare medical condition characterised by microangiopathic haemolytic anaemia, thrombocytopenia, and acute kidney injury. Neurological complications are documented but rarely involve the cerebellum. We present a unique case of a 23-month-old male with HUS triggered by Escherichia coli-O157 (E.coli-O157) infectio...

INTRODUCTION Bevacizumab (BEV) is increasingly used for PLGGs in varying manners despite limited evidence. The potential for BEV to preserve or rescue vision in OPGs has not yet been explored. We performed a nationwide UK evaluation of BEV use for PLGG to provide large cohort safety & efficacy (radiological & visual) data. METHODS A retrospective...

Introduction Canavan disease (CD) is a rare autosomal recessive neurodegenerative disorder caused by a deficiency of aspartoacylase A, an enzyme that degrades N-acetylaspartate (NAA). The disease is characterized by progressive white matter degeneration, leading to intellectual disability, seizures, and death. This retrospective study aims to descr...

Purpose Incomplete partition type II (IP-II) is characterized by specific histological features and radiological appearance. It may occur in isolation or in association with an enlarged vestibular aqueduct (EVA). Among those with IP-II and EVA, a subset has a diagnosis of Pendred syndrome. This study aimed to explore the prevalence of isolated IP-I...

Objective Establishing the cause of hearing loss (HL) is important and rewarding, though not without its challenges. While our ability to identify the etiology for HL has improved with advances in scientific knowledge, a significant proportion of cases remain of unknown etiology. Recent protocol changes within the NHS Genomic Medicine Service suppo...

Introduction Foramen magnum stenosis in achondroplasia carries a risk of sudden death. A proportion of these patients benefit from foramen magnum decompression (FMD). The Achondroplasia Foramen Magnum Score (AFMS) was developed to stratify those most at risk. We hypothesise that this score may be reflected in neurophysiological findings. Methods P...

BACKGROUND AND OBJECTIVES Anterior basal encephaloceles are considered a rare entity and are often associated with midline cerebral abnormalities. Those with a large skull base defect and herniation of brain parenchyma in the neonate or young infant present unique challenges for surgical management. METHODS We analyzed the neurosurgical administra...

Objective The objective was to analyze seizure semiology in pediatric frontal lobe epilepsy patients, considering age, to localize the seizure onset zone for surgical resection in focal epilepsy. Methods Fifty patients were identified retrospectively, who achieved seizure freedom after frontal lobe resective surgery at Great Ormond Street Hospital...

Inherited glycosylphosphatidylinositol deficiency disorders (IGDs) are a group of rare multisystem disorders arising from pathogenic variants in glycosylphosphatidylinositol anchor pathway (GPI-AP) genes. Despite associating 24 of at least 31 GPI-AP genes with human neurogenetic disease, prior reports are limited to single genes without considerati...

Developmental and epileptic encephalopathies (DEEs) are a heterogeneous group of epilepsies characterized by early‐onset, refractory seizures associated with developmental regression or impairment, with a heterogeneous genetic landscape including genes implicated in various pathways and mechanisms. We retrospectively studied the clinical and geneti...

Objective Focal epilepsy is common in low‐ and middle‐income countries. The frequency and nature of possible underlying structural brain abnormalities have, however, not been fully assessed. Methods We evaluated the possible structural causes of epilepsy in 331 people with epilepsy (240 from Kenya and 91 from South Africa) identified from communit...

Os odontoideum refers to a rounded ossicle detached from a hypoplastic odontoid process at the body of the axis. The aetiology has been debated and believed to be either congenital or acquired (resulting from trauma). Os odontoideum results in incompetence of the transverse ligament and thus predisposes to atlantoaxial instability and spinal cord i...

Loeys‐Dietz syndrome (LDS) is an autosomal connective tissue disorder commonly presenting with hypertelorism, bifid uvula, aortic aneurysms, and arterial tortuosity. The aim of the present study was to investigate differences in tortuosity index (TI) between genotypes of LDS, possible progression over time and its use as an adjunctive prognostic to...

Hippocampal Sclerosis (HS) can elude visual detection on MRI scans of patients with temporal lobe epilepsy (TLE), causing delays in surgical treatment and reducing the likelihood of postsurgical seizure-freedom. We developed an open-source software that (1) detects HS from structural MRI scans, (2) generalises across a heterogeneous multicentre coh...

The biggest challenge for clinicians and surgeons when it comes to radiological examinations is the ability to request the right modalities and to understand the strengths and limitations of each modality. This is particularly important in paediatric neurosciences where despite magnetic resonance imaging (MRI) being the main imaging modality, there...

Children living with achondroplasia are at an increased risk of developing neurological complications, which may be associated with acute and life-altering events. To remediate this risk, the timely acquisition of effective neuroimaging that can help to guide clinical management is essential. We propose imaging protocols and follow-up strategies fo...

Aim To evaluate a lesion detection algorithm designed to detect focal cortical dysplasia (FCD) in children undergoing stereoelectroencephalography (SEEG) as part of their presurgical evaluation for drug‐resistant epilepsy. Method This was a prospective, single‐arm, interventional study (Idea, Development, Exploration, Assessment, and Long‐Term Fol...

Diagnosing congenital neck masses in the pediatric population can be challenging, since the differential diagnosis often includes rare or unfamiliar entities, and there is overlap in clinical presentation and imaging findings. A thorough understanding of embryology, anatomy, and common lesions in the pediatric neck, along with the typical location,...

Laser ablation for treatment of hypothalamic hamartoma (HH) is a minimally invasive and effective technique used to destroy hamartomatous tissue and disconnect it from the functioning brain. Currently, the gold standard to evaluate the amount of tissue being “burned” is the use of heat maps during the ablation procedure. However, these maps have lo...

Objective Foramen magnum(FM) stenosis can be responsible for acute and chronic damage to the cervicomedullary junction in children with achondroplasia. The bony anatomy and patterns of suture fusion of the FM in this context are incompletely understood, yet becoming increasingly important in the light of novel medical therapies for achondroplasia....

Low-field (<1T) magnetic resonance imaging (MRI) scanners remain in widespread use in low- and middle-income countries (LMICs) and are commonly used for some applications in higher income countries e.g. for small child patients with obesity, claustrophobia, implants, or tattoos. However, low-field MR images commonly have lower resolution and poorer...

Congenital melanocytic naevus (CMN) syndrome, previously termed neurocutaneous melanosis, is a rare disease caused by postzygotic mosaic mutations occurring during embryogenesis in precursors of melanocytes. The severity of neurological manifestations in CMN patients is related to central nervous system abnormalities found at magnetic resonance ima...

Low-field (<1T) magnetic resonance imaging (MRI) scanners remain in widespread use in low- and middle-income countries (LMICs) and are commonly used for some applications in higher income countries e.g. for small child patients with obesity, claustrophobia, implants, or tattoos. However, low-field MR images commonly have lower resolution and poorer...

Simple Summary Head and neck tumors (HNTs) are associated with a high mortality due to their commonly insidious and asymptomatic development. Regarding risk stratification and long-term patient outcome prediction, routine clinical evaluation by radiologists has several limitations. Numerous researchers have assessed the usefulness of radiomics and...

PurposeWe reviewed the genotypes and the imaging appearances of cochleae in CHARGE patients from two large tertiary centres and analysed the observed cochlear anomalies, providing detailed anatomical description and a grading system. The goal was to gain insight into the spectrum of cochlear anomalies in CHARGE syndrome, and thus, in the role of th...

Background and Objective Epilepsy affects approximately 50 million people worldwide, with 30–40% of patients not responding to medication, necessitating alternative therapies such as surgical intervention. However, the accurate localization of epileptogenic lesions, particularly in pediatric magnetic resonance imaging (MRI)-negative drug-resistant...

With the routine use of high-resolution heavily T2-weighted sequences to evaluate patients with hearing deficits, new, subtle phenotypes of cochlear malformations are being discovered and an increasing number of genotype-phenotype correlations are being found through a reverse phenotype approach, which can help guide geneticists. In this brief repo...

Introduction SPRY1 encodes protein sprouty homolog 1 (Spry-1), a negative regulator of receptor tyrosine kinase signalling. Null mutant mice display kidney/urinary tract abnormalities and altered size of the skull; complete loss-of-function of Spry-1 in humans has not been reported. Methods Analysis of whole-genome sequencing data from individuals...

Imaging plays a crucial role in evaluating paediatric patients with non-traumatic head and neck lesions in an emergency setting because clinical manifestations of these entities can overlap. For this reason, radiologists must be familiar with the clinical and imaging findings of prevalent paediatric head and neck emergencies. In this review, we pre...

Objective. We aimed to determine the prevalence of epilepsy and neurodevelopmental disorders, including autism spectrum disorder, in children and adolescents with hypothalamic hamartoma (HH). We also sought to explore the relationship between these neurodevelopmental comorbidities and epilepsy and to establish the predictive value of structural cha...

Objective To determine whether an ictal electroencephalographic (EEG) recording as part of presurgical evaluation of children with a demarcated single unilateral magnetic resonance imaging (MRI) lesion is indispensable for surgical decision‐making, we investigated the relationship of interictal/ictal EEG and seizure semiology with seizure‐free outc...

Background: Bevacizumab is increasingly used in children with Paediatric Low-Grade Glioma (PLGG) despite limited evidence. A nationwide UK service evaluation was conducted to provide larger cohort 'real life' safety and efficacy data including functional visual outcomes. Methods: Children receiving Bevacizumab-based treatments (BBT) for PLGG (20...

Background and purpose: An "unwound" or "offset" cochlea has been described as a characteristic imaging feature in patients with branchio-oto-renal syndrome, and recently recognized to be associated in particular to those with EYA1 gene mutations. Determination of this feature has traditionally relied on subjective visual assessment. Our aim was t...

Pediatric neuroradiology is a subspecialty within radiology, with possible pathways to train within the discipline from neuroradiology or pediatric radiology. Formalized pediatric neuroradiology training programs are not available in most European countries. We aimed to construct a European consensus document providing recommendations for the safe...

Imaging investigations are critical in the management of children with suspected and confirmed osteopetrosis. In severe cases, imaging can provide rapid confirmation of the diagnosis, whilst in milder cases, imaging findings may be the first or only indicators of the disease. Imaging can also identify major complications, including fractures and ne...

One outstanding challenge for machine learning in diagnostic biomedical imaging is algorithm interpretability. A key application is the identification of subtle epileptogenic focal cortical dysplasias (FCDs) from structural MRI. FCDs are difficult to visualize on structural MRI but are often amenable to surgical resection. We aimed to develop an op...

The fifth edition of the World Health Organization Classification of Tumours of the Central Nervous System (WHO CNS5) published in 2021 builds on the 2016 edition and incorporates output from the Consortium to Inform Molecular and Practical Approaches to CNS Tumour Taxonomy (cIMPACT-NOW). WHO CNS5 introduces fundamental changes to brain tumour clas...

Congenital orbital teratomas are rare entities with few case reports detailing their prenatal and perinatal imaging features. We present the case of a congenital orbital teratoma initially detected as cystic lesion on prenatal ultrasound, with foetal and postnatal imaging showing evolution of characteristic MRI appearances. Knowledge of these appea...

Background and purpose: Pathogenic somatic variants affecting the genes Histone 3 Family 3A and 3B (H3F3) are extensively linked to the process of oncogenesis, in particular related to central nervous system tumors in children. Recently, H3F3 germline missense variants were described as the cause of a novel pediatric neurodevelopmental disorder. W...

BACKGROUND: Despite high survival, paediatric optic pathway hypothalamic gliomas are associated with significant morbidity and late mortality. Those youngest at presentation have the worst outcomes. METHODS: We aimed to assess presenting disease, tumour location and treatment factors implicated in the evolution of neuroendocrine, metabolic and neur...

INTRODUCTION: Bevacizumab/Irinotecan is currently 3rd-line treatment in the UK for progressive Paediatric Low-Grade Glioma (PLGG) based on limited evidence. A nationwide service evaluation was conducted to review its safety and efficacy amongst a larger cohort. METHODS: Data from children with PLGG receiving Bevacizumab-based Treatments (BBT) from...

Management of infant medulloblastoma remains a challenge. Front-line chemotherapy can successfully avoid radiation in low-risk infant medulloblastoma. Patients that do relapse can be salvaged long-term with radiotherapy. We report 4 cases of infants with medulloblastoma treated with chemotherapy (HIT2000 protocol) with residual or progressive disea...

BACKGROUND: Paediatric High Grade Gliomas (HGG) have poor outcomes with conventional treatment. HGG in association with constitutional DNA mismatch repair deficiency (CMMRD) are hypermutated and have shown dramatic response to checkpoint inhibitors. Salvage following progression or failure to respond to check point inhibitors has rarely been report...

INTRODUCTION: The treatment aim of childhood optic pathway glioma (OPG) is visual preservation. However, long-term outcomes and prognostic factors implicated remain largely unknown. METHODS: We undertook a retrospective study of infants and young children (IYC) ≤3 years with OPG and logMAR visual acuity (VA) at baseline/follow-up. We derived Overal...

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 c...

Children present with a spectrum of head and neck pathologies that differ from those found in the adult population, with specific image findings and clinical characteristics. This article reviews the imaging protocols, pearls and pitfalls, and mimics of pediatric head and neck lesions, stressing the combination of key radiological findings, clinica...

Congenital orbital teratomas are rare entities with few case reports detailing their prenatal and perinatal imaging features. We present the case of a congenital orbital teratoma initially detected as cystic lesion on prenatal ultrasound, with fetal and postnatal imaging showing evolution of characteristic MRI appearances. Knowledge of these appear...

As survival after pediatric intensive care unit (PICU) admission has improved over recent years, a key focus now is the reduction of morbidities and optimization of quality of life for survivors. Neurologic disorders and direct brain injuries are the reason for 11–16% of admissions to PICU. In addition, many critically ill children are at heightene...