MRL of influenza encephalopathy in children: Value of diffusion-weighted imaging

Purpose: Our purpose was to describe the MR findings of influenza encephalo pathy and assess the value of diffusion-weighted imaging for its diagnosis. Method: We examined a total of five patients diagnosed as having influenza encephalopathy or encephalitis by MRI, including diffusion-weighted imaging . We analyzed the conventional images and compared them with diffusion-weig hted images. Results: Abnormally hyperintense lesions of varying extent and location wer e noted on T2-weighted and fluid-attenuated inversion recovery images in th e cortex and adjacent white matter in every case. They showed no contrast e nhancement. Diffusion-weighted imaging demonstrated the lesions as areas of restricted proton diffusion more clearly than conventional imaging. Conclusion: Influenza encephalopathy is depicted as areas of T2 elongation having a rather nonspecific distribution. Diffusion-weighted imaging can de monstrate the lesions sensitively and serve as a valuable adjunct to conven tional MRI.