目的：探查大型、巨大型垂体腺瘤周围重要结构的变异情况。方法：在１９例垂体瘤病人进行显微手术切除术时，观察其变异情况。结果：１）视神经、视交叉全部被牵拉、受压、抬高，部分与肿瘤发生粘连。２）鞍膈全部向上隆起，在肿瘤上长出分叶的小肿瘤处鞍膈破溃。垂体柄被挤压在鞍膈的后下方。３）视交叉池不完整，在粘连及垂体柄进入鞍膈处，蛛网膜下腔已经消失；在肿瘤挤压（包括动脉）处，蛛网膜下腔仅为一潜在腔隙。４）凡被肿瘤挤压、包围、发生粘连的硬脑膜、神经及血管均有肿瘤新生血管形成。结论：大型、巨大型垂体腺瘤对周围重要结构产生挤压，发生粘连，部分蛛网膜下腔消失，并有肿瘤新生血管形成。以上异常与肿瘤大小及生长方向直接相关。了解上述规律，有利于提高手术疗效 Objective: To explore the variability of important structures around large, giant pituitary adenomas. Methods: When 19 patients with pituitary tumors underwent microsurgical resection, their variation was observed. Results: 1) The optic nerve and the optic chiasm were all pulled, compressed and raised, and some of them had adhesion to the tumor. 2) The saddle ridge bulges upwards, and a small tumor that grows in the tumor on the tumor breaks down. The pituitary stalk is pressed below the saddle ridge. 3) The optic chiasm pool is incomplete and the subarachnoid space has disappeared at the point where the adhesion and the pituitary stalk enter the saddle. At the tumor compression (including the arteries), the subarachnoid space is only a potential lacuna. 4) Tumor neovascularization occurs in all dura mater, nerves, and blood vessels that are squeezed, surrounded, and adhered by tumors. Conclusions: Large, giant pituitary adenomas squeezing vital surrounding structures, causing adhesions, some of the subarachnoid space disappearing, and tumor neovascularization. The above abnormalities are directly related to tumor size and growth direction. Understanding the above rules will help improve the curative effect