Neuroimaging of Migrational Disorders in Pediatric Epilepsy

(A) An axial T2 weighted MRI of the brain of an 8 year old patient shows a subtle focus of cortical thickening in the inferior right frontal lobe, suggestive of focal cortical dysplasia (arrow). (B) A fused PET-MRI shows mild decreased radiotracer uptake in the right inferior temporal lobe, right operculum and right inferior frontal region (arrows). (Color version of figure is available online.)

Regional gray matter heterotopias: T1-weighted image show extensive nodular areas with signal intensity similar to gray matter in the periventricular white matter (brackets). (Color version of figure is available online.)

Focal gray matter heterotopias. Coronal T1 (A) and T2 (B) images showing a focal nodular area with signal similar to gray matter in the left frontal periventricular white matter (arrow). (Color version of figure is available online.)

Focal cortical dysplasia. (A) Postcontrast axial T1 image shows a subtle area of nonenhancing low signal extending from the left frontal gray matter into the periventricular white matter (arrow). (B) Focal cortical dysplasia. Axial T2 image showing high signal extending from the left frontal cortex into the periventricular white matter (arrow), typical for type II focal cortical dysplasia (arrow). (Color version of figure is available online.)

Polymicrogyria. Sagittal T1 image shows the insular cortex is composed of small irregular appearing gyri (arrow). (A) This subtle finding is better appreciated when compared to the contralateral normal side (arrow) (B). (Color version of figure is available online.)

Polymicrogyria. Axial T1 image shows the right insular and adjacent cortex is composed of numerous small irregular gyri (arrow). (Color version of figure is available online.)

Type I Schizencephaly (closed lip). Axial T2 (A) and T1 (B) weighted images show a subtle beaking of the ventricle (arrow). There is heterotopic grey matter lining the ventricle and extending from the ventricle to the surface of the brain. (Color version of figure is available online.)

Schizencephaly Type II (open lip). Axial T2 image shows grey matter-lined parenchymal cleft extending from right lateral ventricle to the subarachnoid space (arrow). (Color version of figure is available online.)

Lissencephaly. Axial (A) and coronal (B) T2 images show diffuse lack of gyrations throughout the cortex and a smooth contour to the cerebrum in this full-term neonate. Thick diffuse band heterotopia is present (arrows). (Color version of figure is available online.)

Hemimegalencephaly. Axial T1 (A) and T2 (B) images show diffuse abnormal enlargement of the right cerebral hemisphere, with corresponding asymmetry of the skull. In this case, there are no focal areas of abnormal cortical development.

Congenital cytomegalovirus. (A) Coronal computed tomography shows ventriculomegaly, extensive coarse calcifications lining the walls of the lateral ventricles, and abnormal hypodensity in the periventricular white matter. (B) Coronal T2-weighted MRI better illustrates the abnormally thin parenchyma with ventriculomegaly. Gradient recalled echo images (not shown) depicted all the periventricular chunky calcifications as low-signal areas.