Erratum: Definitions and classification of malformations of cortical development: Practical guidelines (Brain (2020) 143 (awaa174) DOI: 10.1093/brain/awaa174)

The authors apologize for an error in the legend for Figure 4, which should read as follows: Figure 4 Imaging characteristics of grey matter heterotopia. (A and B) Single, unilateral periventricular nodular heterotopia. Single subependymal heterotopic nodule in the left paratrigonal region is isointense to grey matter on both T1-and T2-weighted images (arrow). (C and D) Multiple, bilateral periventricular nodular heterotopia. There are bilateral heterotopic nodules causing distortion of the bilateral trigonal margins (arrows). (E and F) Laminar heterotopia. There is a smooth, curvilinear heterotopic layer (arrows) associated with white matter abnormalities and overlying gyral simplification. (G and H) Subcortical, transmantle curvilinear heterotopia. In this patient with concurrent corpus callosum agenesis and an interhemispheric cyst, there is a large, convoluted grey matter heterotopia that curves across the whole thickness of the right cerebral hemisphere. (I and J) Brain in brain malformation. Giant, gyriform heterotopia replaces most of the left hemisphere. Overlying cortex is also abnormal (arrowheads) and there is concurrent corpus callosum agenesis. (K and L) Aventriculy. Grossly malformed, uncleaved telencephalon with extensive cortical malformation is associated with absence of the lateral and third ventricles (case courtesy of William B. Dobyns, USA). (M and N) Ribbon-like heterotopia. There is an undulated subcortical grey matter ribbon involving both hemispheres symmetrically. Overlying cortex is polymicrogyric, and there is corpus callosum agenesis. EML1 mutations have been recently described to cause this pattern (case courtesy of Jana Rydland, Norway). (O and P) Diffuse band heterotopia. In this female with DCX mutation, grey matter heterotopia band extends across the white matter of both hemispheres in a symmetric fashion. Both outer and inner heterotopia margins are smooth. Overlying gyrification is simplified. (Q and R) Posterior band heterotopia. Smooth-marginated heterotopia bands are present only in the parietal regions, in between normally myelinated white matter. Overlying gyrification is slightly simplified. This has now been corrected.