髄膜腫の自然経過の画像予測

Prediction of the Natural Course of Meningioma Using CT and MR Images

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・近年，無症候性髄膜腫の成長型の分類が確立されてきた．

・髄膜腫の腫瘍増大を予測する画像所見がわかってきた．

・髄膜腫の腫瘍増大の停止を予測する画像所見がわかってきた．

　The frequency of identification of asymptomatic meningiomas is increasing owing to the advancement and widespread use of CT and MRI. The first choice for asymptomatic meningiomas is observation. Approximately 70% of asymptomatic meningiomas increase in volume on long term follow-up. More than half of them reportedly exhibit a self-limiting pattern, in which growth eventually stops. Imaging findings related to increased meningioma volume include no calcification, large tumor size, high signal intensity inside the tumor on T2-weighted images, high brightness within the tumor on diffusion-weighted images, and perifocal edema. We also highlighted the presence of hypo-intensity of the surface layer on T2-weighted imaging, indicating growth arrest in a self-limiting growth pattern of meningioma.

　In this article, literature reports on image prediction using CT and MRI regarding the growth of asymptomatic meningiomas were reviewed, along with our report.