10岁女，因发现第三脑室占位1月入院

CT:第三脑室内显示混杂密度肿块影，形态不规则，密度不均，见有分叶，大小约4.6×4.3CM。病灶周围未见明显水肿带，第三脑室及两侧脑室积水增大，中线结构左偏。

第三脑占位性病变（考虑为室管膜瘤）并脑积水，

弥漫性星形细胞肿瘤，I级。

少突胶质瘤？

In this location, ependymoma (Clear cell type) and central neurocytoma should be in the top of ddx, immunostains should be helpful.Good luck.

弥漫性星型细胞肿瘤

Tumor tissue was not seen in these photos. No evidence to make a diagnosis of astrocytoma or ependymoma.

图789是污染