Magnetic resonance imaging in occipital lobe epilepsy with frequent seizures.
Magnetic resonance imaging and single-photon emission computed tomography provide useful information in the evaluation of the pathophysiology of epileptic foci. Ictal magnetic resonance imaging in a 7-year-old male with occipital lobe epilepsy revealed mild swelling of the left temporo-occipital region, with hyperintensity on T(2)-weighted and fluid attenuated inversion recovery images. This lesion, however, was not detected on diffusion-weighted imaging. An ictal single-photon emission computed tomography study using 99mTc-ECD demonstrated left temporo-occipital hyperperfusion. T(2)-weighted and fluid attenuated inversion recovery images revealed hyperintensity without atrophy 4 months after control of his seizures. The focus in nonconvulsive status epilepticus has been reported as showing hyperintensity on T(2)-weighted, fluid attenuated inversion recovery and diffusion-weighted images. Since hyperintensity on diffusion-weighted imaging reflects cytotoxic intracellular edema due to excitotoxicity, and his ictal diffusion-weighted image exhibited no remarkable change, the lesions in the left temporo-occipital region resulted from vasogenic edema. Cytotoxic edema resulting from excitotoxicity leads to neuronal death, causing cortical atrophy. Thus, diffusion-weighted imaging is a useful tool to predict the prognosis of frequent seizures.
Hattori
Hideji
H
Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
Matsuoka
Osamu
O
Ishida
Hiroshi
H
Hisatsune
Saeri
S
Yamano
Tsunekazu
T
D002648:Child; D004828:Epilepsies, Partial / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012640:Seizures / Q000150:complications / Q000175:diagnosis*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods