Sm. Sisodiya et Sl. Free, DISPROPORTION OF CEREBRAL SURFACE-AREAS AND VOLUMES IN CEREBRAL DYSGENESIS - MRI-BASED EVIDENCE FOR CONNECTIONAL ABNORMALITIES, Brain, 120, 1997, pp. 271-281
In the normal adult human brain, there are quantitative relationships
between a surface area I?measure of the grey matter and the volume of
hemispheric grey matter the volume of the hemispheric subcortical matt
er and the cross-sectional area of the corpus callosum as revealed by
analysis of high resolution MRI data. These relationships reflect stru
ctural order in, and biological features of normal human cerebral hemi
spheres. Cerebral dysgenesis (CD) is associated with disruption of the
normal organization of the hemispheres to a greater or lesser extent
and is often manifest as refractory epilepsy. We have examined structu
ral proportions and their disruption in the brains of patients with ep
ilepsy and CD. We found that structural measures were abnormal in 60%
of patients with CD, with abnormalities in 64% of hemispheres that, on
visual inspection alone, appeared completely normal. We showed that t
he disruptions found are compatible with expected histopathology in ca
ses where histopathology may be predictable, and that extensive abnorm
alities may be due to abnormal patterns of connections within the hemi
spheres. In some cases, it may be possible to predict histopathology o
n the basis of quantitative analyses of high resolution MRI data, wize
n such prediction is not possible on visual inspection alone.