Hemiconvulsion-hemiplegia-epilepsy syndrome. Magnetic resonance findings in a 3-year-old boy

Abstract

The term ‘hemiconvulsion-hemiplegia-epilepsy syndrome’ (HHE) was first used by Gastaut et al. to describe the sequential combination of unilateral or predominandy unilateral clonic seizures (hemiconvulsion), occurring during the first 2 years of life, immediately followed by an ipsilateral flaccid hemiplegia lasting 7 or more days. In the following phase partial epileptic seizures occur.

We report a case of HHE syndrome in a 3-year-old boy with partial seizures (hemiconvulsion lasting 15–30 minutes) followed by left hemiplegia and hyporeflexia. Magnetic resonance imaging showed diffuse and high signal hyperintensity of the whole right cerebral hemisphere. Diffusion-weighted images showed a reduction of the apparent diffusion coefficient in the subcortical region. Magnetic resonance arteriography showed a narrow flow signal in the distal territory of the right middle cerebral artery. The authors emphasize the importance of neuroradiological findings in early diagnosis and in the follow-up of HHE syndrome.