MRI features and diagnosis of Rasmussen encephalitis in children

REN Yanjun; YANG Yanhui; ZHAI Shuo; LU Jie; LI Kuncheng

Abstract：Objective To analyze the characteristics of MRI manifestations of Rasmussen encephalitis in children, and to improve the understanding and diagnostic level of the disease. Methods MRI findings and clinical data were analyzed retrospectively in 9 patients with Rasmussen encephalitis confirmed by clinical or pathology, including 5 cases of male, 4 cases of female, with an average age of 7.3 years and the average onset age of 4.7 years, then, abnormal signals in the brain and brain atrophy change and progress were evaluated. Results MRI features of 9 cases of Rasmussen encephalitis included: 1) signal abnormality: T2WI and FLAIR hyperintensity (8/9) in the cortex and subcortical layer, and two or more cerebral leaves (5/8), especially in the frontal parietal lobes; Caudate nucleus or shell nuclei high signal (5/8); no abnormality in the MRI signal (1/9); 2) the brain atrophy (8/9): small local gyrus and widened sulci in the isolateral hemisphere (7/8), atrophy in caudate nucleus and putamen (5/8), lateral fissure broadened (7/8), temporal Angle (8/8) and lateral ventricle expanded (5/8), late cortical atrophy lesions for hemisphere (7/8); 3) progression of the lesion (3/9): 3 patients with follow-up MRI showed an increase in abnormal signal range in the lateral hemispheric cortex and increased brain atrophy. Conclusion MRI findings demonstrated rasmussen encephalitis for children have higher value to evaluate the diagnosis and prognosis of the disease, and its characteristics including unilateral cortical or subcortical T2 and FLAIR hyperintensity, progressive brain atrophy such as enlargement of lateral ventricle, lateral fissure and sulci, the deep gray matter nuclei may be involved. So, understanding the certain MRI characteristics can help to improve the level of diagnosis of the disease.