Clinical and neuroimaging findings in children with gray matter heterotopias: A single institution experience of 36 patients

X-linked neuronal migration disorders: Gender differences and insights for genetic screening

Cortical development depends on neuronal migration of both excitatory and inhibitory interneurons. Neuronal migration disorders (NMDs) are conditions characterised by anatomical cortical defects leading to varying degrees of neurocognitive impairment, developmental delay and seizures. Refractory epilepsy affects 15 million people worldwide, and it is thought that cortical developmental disorders are responsible for 25% of childhood cases. However, little is known about the epidemiology of these disorders, nor are their aetiologies fully understood, though many are associated with sporadic genetic mutations. In this review, we aim to highlight X-linked NMDs including lissencephaly, periventricular nodular heterotopia and polymicrogyria because of their mostly familial inheritance pattern. We focus on the most prominent genes responsible: including DCX, ARX, FLNA, FMR1, L1CAM, SRPX2, DDX3X, NSHDL, CUL4B and OFD1, outlining what is known about their prevalence among NMDs, and the underlying pathophysiology. X-linked disorders are important to recognise clinically, as females often have milder phenotypes. Consequently, there is a greater chance they survive to reproductive age and risk passing the mutations down. Effective genetic screening is important to prevent and treat these conditions, and for this, we need to know gene mutations and have a clear understanding of the function of the genes involved. This review summarises the knowledge base and provides clear direction for future work by both scientists and clinicians alike.

Gri Cevher Heterotopisi Bulunan Pediatrik Hastaların Manyetik Rezonans Görüntüleme Bulguları ve Eşlik Eden Malformasyonların Değerlendirilmesi

Objective: The aim of the present study is to classify gray matter heterotopias according to magnetic resonance imaging findings and to define the accompanying malformations. Methods: Images of all pediatric patients who were detected to have heterotopia in brain magnetic resonance imaging between January 2012 and June 2020 were retrospectively evaluated. The type, location of heterotopia, and accompanying cerebral anomalies were analyzed. Results: A total of 42 patients, 22 male, and 20 female, with a mean age of 7.80 ± 4.53 years (2-16 years) with gray matter heterotopia were included in the study. Of the patients, 33 (78.6%) had subependymal, 7 (16.7%) had subcortical, and 2 (4.7%) had band heterotopia. Twenty-four patients had epilepsy. Conclusion: The sub ependymal heterotopias were frequently located in the trigon region of the lateral ventricles. All subcortical heterotopias were in the frontal and unifocal locations. Band heterotopias were located bilaterally and subcortically in a symmetrical fashion in the cerebral hemisphere. The main accompanying anomalies were ventriculomegaly, Arnold-Chiari malformation, and corpus callosum agenesis. Considering the neurological developments of pediatric patients, it is important to identify the type of heterotopia and accompanying anomalies for patient management.

Gray matter heterotopia: clinical and neuroimaging report on 22 children

OBJECTIVE

To investigate the clinical characteristics and neuroimaging features of childhood presenting with gray matter heterotopia observed in a single tertiary Pediatric Department in Catania and compare the data with those reported in the literature.

METHODS

A retrospectively review of the history, clinical findings, electrophysiological features and magnetic resonance images of 22 children presenting with gray matter heterotopia observed from January 2010 to January 2020.

RESULTS

Among the 22 children included in the study, 17 presented with periventricular heterotopia (PVNH), two with Subcortical Band Heterotopia (SBH), and three with other subcortical heterotopia (SUBH). In the affected children, the ages at first diagnosis ranged from 3 months to 16 years with a mean age of 8.2 years (± 5.4); twelve (54.5%) suffered by developmental delay and intellectual deficit; eleven children (50%) complained of epileptic seizures, mostly focal to bilateral tonic-clonic seizure. In addition, in the periventricular heterotopia group (PVNH), cerebral and systemic malformations were reported in twelve (70%) and in ten (58%) children, respectively, out of seventeen. In the SBH plus SUBH group, epileptic seizures were recorded in 3 (60%) out of 5 children, cerebral malformations in one child and systemic malformations in two children.

CONCLUSIONS

Heterotopic gray matter malformations include a group of disorders that manifest with a variety of neurological implications, such as cognitive impairment and epilepsy, and often related with epilepsy, other cerebral malformations and systemic anomalies.

Hypothalamic Hamartoma, Gray Matter Heterotopia, and Polymicrogyria in a Boy: Case Report and Literature Review

BACKGROUND

Hypothalamic hamartomas (HHs) are rare, and it is even rarer when combined with gray matter heterotopia (GMH) and polymicrogyria (PMG).

CASE DESCRIPTION

A 5-year-old boy with HH, GMH, and PMG was retrospectively evaluated. The clinical data, including the symptoms, examinations, diagnosis, and treatment, were collected. The patient had a chief complaint of gelastic seizures and intellectual deficiency. Brain magnetic resonance imaging showed HH, paraventricular nodular heterotopia, and PMG. Video electroencephalographs were normal. The patient underwent resection of the HH via transcallosal transseptal interforniceal approach. Seizures disappeared immediately after complete resection of HH, and the intellectual development improved.

CONCLUSIONS

In this extremely rare case, resection of the HH eliminated the symptoms. Nonetheless, we still need to be cautious about the possible epilepsy that may be caused by GMH and PMG.

The clinical and imaging features of gray matter heterotopia: a clinical analysis on 15 patients

OBJECTIVE

To investigate the clinical and imaging features of gray matter heterotopia (GMH) and improve the clinicians' understanding of the disease.

METHODS

A retrospective study was performed on 15 patients with GMH diagnosed at The Affiliated Hospital of Xuzhou Medical University from November 2014 to November 2016. Their clinical and imaging features are also summarized.

RESULTS

The proportion of male and female patients was 2:1. The age of onset was 2~45 years and the average age was 19.1 years. There were 13 patients with epilepsy who also had cognitive decline (5 cases) and neurological deficit (3 cases). There were 2 patients with headache or dizziness. The imaging findings of GMH are unilateral or multiple spots in the periventricular or subependymal, subcortical, and centrum semiovale and are often accompanied by other cerebral malformations. We found that 10 patients had the subcortical type of GMH and 5 patients had the subependymal type or periventricular nodular heterotopia type. There were 8 cases of ventricular compression, 5 cases of ventriculomegaly, 5 cases of cerebral fissure malformation, 3 cases of pachygyria, 1 case of callosal agenesis, and 1 case of undeveloped septum pellucidum. All the patients were given symptomatic and supportive therapies and 3 patients were treated with antiepileptic drugs. Seizures were, however, poorly controlled.

CONCLUSION

GMH should also be suspected in patients with juvenile onset of seizures, cognitive decline, and neurological deficits. Magnetic resonance scans may show lesions in the white matter of the brain with signals similar to the normal gray matter.