Abstract
ObjectiveTo investigate the quantitative diffusion properties of the corpus callosum (CC) in a large group of patients with periventricular nodular heterotopia (PNH) related epilepsy and to further investigate the effect of Filamin A (FLNA) mutation on these properties.MethodsPatients with PNH (n = 34), subdivided into FLNA-mutated (n = 11) and FLNA-nonmutated patients (n = 23) and healthy controls (n = 34), underwent 3.0 T structural MRI and diffusion imaging scan (64 direction). Fractional anisotropy (FA) and mean diffusivity (MD) were measured in the three major subdivisions of the CC (genu, body and splenium). Correlations between DTI metric changes and clinical parameters were also evaluated. Furthermore, the effect of FLNA mutation on structural integrity of the corpus callosum was examined.ResultsPatients with PNH and epilepsy had significant reductions in FA for the genu and splenium of the CC, accompanied by increases in MD for the splenium, as compared to healthy controls. There were no correlations between clinical parameters of epilepsy and MD. The FA value in the splenium negatively correlated with epilepsy duration. Interestingly, FLNA-mutated patients showed significantly decreased FA for all three major subdivisions of the CC, and increased MD for the genu and splenium, as compared to HCs and FLNA-nonmutated patients.ConclusionsThese findings support the conclusion that patients with epilepsy secondary to PNH present widespread microstructural changes found in the corpus callosum that extend beyond the macroscopic MRI-visible lesions. This study also indicates that FLNA may affect white matter integrity in this disorder.
Highlights
Malformations of cortical development (MCDs) include a diverse range of disorders that result from defects in the complex process of brain cortical genesis, and are common causes of neurodevelopmental delay and epilepsy (Guerrini and Dobyns, 2014; Leventer et al, 1999)
We found that certain segments of the corpus callosum demonstrate decreased Fractional anisotropy (FA) and increased mean diffusivity (MD) in Periventricular nodular heterotopia (PNH) patients compared to healthy controls, and the correlation between FA in the splenium and epilepsy duration
The differences between Filamin A (FLNA)-mutated and FLNA-nonmutated cases are evident, suggesting that PNH is associated with altered white matter integrity, and that FLNA mutations may influence white matter microstructure
Summary
Malformations of cortical development (MCDs) include a diverse range of disorders that result from defects in the complex process of brain cortical genesis, and are common causes of neurodevelopmental delay and epilepsy (Guerrini and Dobyns, 2014; Leventer et al, 1999). Several studies have reported morphometric abnormalities in the corpus callosum (CC) (Pardoe et al, 2015; Pisano et al, 2012), and significant diffusion tensor imaging (DTI) metric alterations in the CC (Andrade et al, 2014), as well as other perinodular regions (Filippi et al, 2013) in this disease. Together, these findings confirm the presence of microstructural abnormalities in PNH and provide preliminary support for a diffusion-based endophenotype of this disorder (Kini et al, 2016). Whether the observed CC alterations are related to clinical features, such as epilepsy duration, or differ with respect to FLNA mutation, remains an open question
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
