Cystic cerebellarastrocytoma comprises about 33% of all posterior fossa tumors in children.
囊性星形细胞瘤占儿童后颅窝肿瘤的33%。
2
But the sign can not be found in all 32 cases with intra-cerebral glioma, including 21 cases with astrocytoma and 4 cases with oligodendroglioma and 7 cases with ependymoma above cerebellar tentorium.