A Case of Medial Medullary Syndrome Detected by Diffusion weighted Magnetic Resonance Imaging

We report an 84-year-old woman with medial medullary syndrome diagnosed by diffusion-weighted magnetic resonance imaging (MRI). She was admitted because of left hemiparesis and hypesthesia. T2 weighted and diffusion-weighted MRI showed a high signal lesion at the right medial medulla oblongata 10 days after the onset. It is well known that diffusion-weighted MRI is useful for detecting supratentrial cerebral ischémie lesions in the extremely acute stage. However, to our knowledge, there have been only a few reports of diffusion-weighted MKI in patients with ischémie stroke of the medulla oblongata. Normal nerve fibers in the direction perpendicular to the motion probing gradient (MPG) shows a high signal by diffusion weighted MRI (anisotropy of apparent diffusion cofficient [ADC] ). Normal nerve fibers in the pyramidal tract of medulla oblongata also shows a high signal when the MPG pulse is applied in the x and y directions. We solved this problem by using isotropic diffusion weighted imaging and were able to detect ischémie lesion of medial medullarv infarction in the acute ohase.