Introduction: Hemimegalencephaly is a well-known congenital malformation. However, localized megalencephaly, which may be one of the subtypes of hemimegalencephaly, has not been separately investigated. In the present study, we attempted to characterize the clinical and magnetic resonance (MR) imaging features of localized megalencephaly in comparison with ordinary diffuse hemimegalencephaly and multilobar cortical dysplasia.
Methods: MR findings for 43 patients with hemimegalencephaly and ten with multilobar cortical dysplasia, which is the differential diagnosis of localized megalencephaly, were retrospectively reviewed. Clinical findings such as the onset and severity of seizures and imaging findings including the affected area of the brain, structures outside of the hemisphere, and interval morphological changes were examined.
Results: Of the 43 patients, 11 showed signs of localized megalencephaly (25.6%). Localized megalencephaly was predominantly seen on the left side (72.7%) and had a tendency toward severe-grade seizures compared to multilobar cortical dysplasia. The frequencies of the extracerebral abnormalities in the diffuse hemimegalencephaly, localized megalencephaly, and multilobar cortical dysplasia groups were 84.4%, 36.4%, and 0.0%, respectively. There were three localized megalencephaly patients whose affected areas shrank and whose images were similar to those of multilobar cortical dysplasia.
Conclusion: Localized megalencephaly accounts for one quarter of all hemimegalencephaly cases in this study. The incidence of extracerebral abnormalities in patients with localized hemimegalencephaly was almost half that of patients with diffuse hemimegalencephaly. Extracerebral abnormalities were absent in patients with multilobar cortical dysplasia. Associated extracerebral abnormalities may be a clue to differentiating localized megalencephaly from multilobar cortical dysplasia.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00234-009-0579-7 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A phase II double-blind multicentre, placebo-controlled trial to assess the efficacy and safety of alpelisib (BYL719) in paediatric and adult patients with Megalencephaly-CApillary malformation Polymicrogyria syndrome (MCAP): the SESAM study protocol.
BMJ Open
December 2024
INSERM UMR1231 Génétique des Anomalies du Développement (GAD), Université de Bourgogne, Dijon, France.
Introduction: The megalencephaly capillary malformation polymicrogyria (MCAP syndrome) results from mosaic gain-of-function variants. The main clinical features are macrocephaly, somatic overgrowth, neurodevelopmental delay and brain anomalies. Alpelisib (Vijoice) is a recently FDA-approved PI3Kα-specific inhibitor for patients with PIK3CA-related overgrowth spectrum (PROS).
View Article and Find Full Text PDFPIK3CA-Related Overgrowth Spectrum: Exploring Brain Growth From Fetal to Infant.
Pediatr Neurol
November 2024
Department of Neonatology, Unidade Local de Saúde de Vila Nova de Gaia, Vila Nova de Gaia, Portugal.
Article Synopsis
- MCAP (Megalencephaly-capillary malformation-polymicrogyria syndrome) is a rare neurological disorder caused by mutations in the PIK3CA gene, leading to abnormal brain growth, vascular issues, and body overgrowth.
- A clinical report details an infant diagnosed with MCAP, who showed signs of the disorder from prenatal imaging, which identified megalencephaly and a confirmed PIK3CA mutation postnatally, followed by early medical interventions.
- Despite these interventions, the patient faced ongoing challenges such as macrocrania, hydrocephalus, and neurodevelopmental delays, highlighting the importance of multidisciplinary care and monitoring to manage the complexities of the disorder and emphasizing potential future therapies for better outcomes.
Somatic variant analysis of resected brain tissue in epilepsy surgery patients.
Epilepsia
December 2024
Department of Child Neurology, University Medical Center Utrecht Brain Center, Utrecht, the Netherlands.
Article Synopsis
- * A pathogenic variant was found in 31% of the total cases analyzed, with higher rates in specific conditions like focal cortical dysplasia type II (33%) and hemimegalencephaly (62%), particularly involving the mTOR signaling pathway.
- * The identification of germline and somatic variants, especially in focal epilepsy genes, provides insights for future analyses on genetic factors related to surgical outcomes, which could enhance patient counseling and treatment plans.
Multi-disciplinary team approach for pediatric hemimegalencephaly: Insights from a single institutional case series.
Epilepsia Open
December 2024
Division of Pediatric Neurology, Department of Pediatrics, David Geffen School of Medicine, UCLA Mattel Children's Hospital, Los Angeles, California, USA.
Recent genetic studies have revealed that hemimegalencephaly (HME) is a multi-system disorder associated with germline or mosaic variants within the PI3K-mTOR-GATOR1 signaling pathways. Patients with HME typically develop drug-resistant epilepsy necessitating extensive evaluation, hemispherectomy, and long-term management. We describe the role of a multidisciplinary team (MDT) for the diagnosis and management of recent patients with HME at UCLA who underwent hemispherectomy.
View Article and Find Full Text PDFNovel Variant ANKRD11 Gene Mutation Associated With Drug-Resistant Epilepsy in KBG Syndrome Phenotype.
Pediatr Neurol
June 2024
Faculty of Medicine, University Clinic for Neurology, Ss. Cyril and Methodius University, Skopje, North Macedonia.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!