小脑桥脑角（CPA）肿瘤绝大多数是中轴外肿块（EM），多起源于第皿脑神经的听神经瘤和起源于脑膜的脑膜瘤。脑实质内肿瘤多为中轴内肿块（IM），它向外生长突出于A区时，在临床上和放射学上与EM极为相似。本文报告3例类似CPA区EM表现的IM：桥脑成神经管细胞瘤，小脑星形细胞瘤 The vast majority of CPA tumors are extraaxial axons (EM), many of which originate from the digitio-cranial nerves and meningiomas that originate in the meninges. Most of the brain parenchymal tumors were intra-axial masses (IM), which are clinically and radiologically similar to EM when they protrude outward in zone A. This article reports 3 cases of similar performance of EM in the CPA area IM: pontine medulloblastoma, cerebellar astrocytoma