Answer of January 2008

Clinical History:

28yrs-old man, known to have epilepsy since childhood with frequent attacks.? MRI brain was performed (T1 FLAIR, T2W, T2 Coronal FLAIR and SPGR) :

Diagnosis:

Focal Cortical Displasia

Discussion:

Focal cortical dysplasia is a well-recognized cause of medically refractory epilepsy and is characterized by the presence of abnormal neurons and glia arranged abnormally in focal areas of the cerebral cortex. It is not associated with major abnormal gyration and hence is different from pachygyria, polymicrogyria and hemimegalencephaly.

It is commonly seen in temporal lobe followed by frontal and occipital lobes. Characteristic MR features include gyral thickening (macrogyria), varying degrees of cortical hyperintensity on heavily T1-weighted images (such as magnetization-prepared rapid acquisition gradient-echo images), indistinct gray matter-white matter junctions, hypointensity on T1-weighted images, and hyperintensity on T2-weighted and FLAIR images within the subcortical white matter of affected areas.