目的分析侵袭性垂体腺瘤的的 MRI表现。方法回顾性分析48例MRI诊断 为垂体大腺瘤患者的病例资料，其中34例 经手术、病理证实。结果 肿瘤以等T1、 等或稍长T2信号为主，增强扫描后均匀或 不均匀强化。肿瘤向周围组织侵犯表现为 颈动脉包绕，海绵窦受累；鞍底下陷，部 分肿瘤突入蝶窦，突破鞍隔等。MRI判断4 级受侵19例,3级受侵8例，2级受侵7例，1 级受侵9例，0级受侵5例；术中3-4级均证 实海绵窦受侵犯，颈内动脉部分或完全受 包绕。结论 MRI检查结果与手术具有较好 的一致性，可在术前较客观评估垂体腺瘤 是否具有侵袭性及其侵袭范围，对手术方 式以及术后治疗方案的选择具有重要的临床意义。

Objective To explore the invasive signs on MRI of invasive pituitary adenomas(IPA). Methods A total of 48 patients with giant pituitary adenoma diagnosed by MRI were analyzed, in which, 42 cases were confirmed by surgery. Results The appearance of the tumor was iso-intense on T1WI, iso-intense or high-intense on T2WI, and homogeneously or heterogeneously enhanced after Gd-DTPA injection. MRI findings of invasiveness included encasement of internal carotid artery, invasion of the sella turcica and adjacent bones, involvement of sphenoid sinus and cavernous sinus. 19 cases with grade-4 invasion and 8 cases with grade-3 invasion on MRI were confirmed involvement of cavernous sinus and encasement of internal carotid artery wholly or partly by surgery. Conclusion MRI results have good consistency with the operation. MRI is helpful in evaluating the invasion of pituitary adenomas before operation, which is of great clinical significance for the management of the disease．