A Case of Band Heterotopia with Lennox-Gastaut Syndrome

Yoo, Sang Yeol; Kim, Yun Yee; Kim, Eun Young; Kim, Yong Wook; Kim, Ki Bok

Abstract

Band heterotopia is a rare neuronal migration disorder, resulting in epilepsy and mental retardation. Epilepsy in band heteropopia, of which Lennox-Gastaut syndrome constituted about 20%, varied in nature and degree of severity. Band heterotopia can be diagnosed by brain magnetic resonance imaging (MRI), showing another diffuse layer of gray matter underlying the normal-looking cortex with intervening thin rim of white matter. While positron emission tomography (PET) with [18F]-fluorodeoxyglucose revealed glucose uptake similar to the overlying cortex, single photon emission computerized tomography (SPECT) findings of band heterotopia have not been reported. We report a 8-year-old girl who presented with variable types of generalized seizures and mild mental retardation. She was diagnosed as having band heterotopia with Lennox-Gastaut syndrome by MRI and interictal electroencephalogram (EEG) showing immature background and generalized 2 Hz slow spike and wave complexes. Interictal SPECT, using Tc 99m hexamethyl propylenamine oxime (Tc 99m-HMPAO), revealed the same degree of perfusion in both the areas of band heterotopia and the overlying cortex. By using valproate and lamotrigine, she is now in stable condition with a significant decrease in seizure frequency.