"Negative T2 shine through" in patients with hyperglycemia and seizures: a frequently overlooked MRI pattern.

Epileptic seizures associated with hyperglycemia have a rare but characteristic MR imaging pattern which however is frequently missed. It consists of a T2 hypointensity and an apparent diffusion coefficient (ADC) decrease of the white matter underlying the epileptic cortex; the cortex itself may be DWI hyperintense and show a blood-brain barrier disruption. Prompt diagnosis is relevant since treatment of the hyperglycemic state rather than treatment with anti-epileptic drugs frequently interrupts the seizures. Subcortical T2 hypointensity and ADC decrease may be completely reversible.