MRI引导下氩氦刀冷冻小型猪大脑的实验观察

Experimental observation of cryoablation in miniswine's cerebrum guided by MRI

目的观察MRI引导下氩氦刀冷冻正常小型猪大脑的急慢性损伤。方法在MRI引导下应用氩氦刀冷冻治疗系统对小型猪左侧顶部大脑进行冷冻消融,饲养3周后同法冷冻右侧顶部脑组织,随即处死动物并取出大脑,10%甲醛溶液固定,将猪大脑整体经顶冠状切片病检。结果第一次冷冻后急性期(1周)饲养观察动物无呕吐。大体标本于陈旧灶局部可见脑萎缩表现,新鲜冷冻灶皮层可见淤血并局部肿胀,边界清楚;镜下观察见陈旧灶大片坏死,其周围环绕明显炎性细胞浸润带;新鲜冷冻灶灰质内有多量破碎的红细胞并淤血;陈旧灶和新鲜灶白质内髓鞘结构均消失。结论氩氦刀冷冻消融可完全破坏正常脑组织,急性期可致脑肿胀,慢性期可引起周围炎性反应。

Objective To observe the acute and chronic impair of cryoablation in normal miniswine＇s cerebrum guided by MRI. Methods A cryoablation focus in the left parietal cerebrum of a miniswine was produced by eryocare surgical system guided by MRI. Three weeks later the same management was implemented in the right parietal cerebrum of the same animal. It was sacrificed immediately, it＇s brain was dislodged entirely and retained by 10% formalin. Pathologic inspection of trans-parietal cerebrum entirety was performed. Results The animal was breaded without vomitting during the acute stage （one week） after the cryoabalation of the first time. In the general specimen, eneephala trophy could be found in olden eryoablation focus, and in fresh eryoablation focus the stagnated blood with cerebral swelling was found obviously in the cortex with clear boundary. Under microscopy, a large area of cellular necrosis existed in olden focus with apparently a round inflammatory cell infiltrating. Sackful cracked red blood cell existed in fresh cryoablation focus. Medullary sheath structure of white substance was all eliminated in the slices of Luxol fast-Blue staining. Conclusion The normal miniswine cerebral tissue could be destroyed completely by eryocare Surgical system. Cerebral swelling could be remained in acute stage, and circular inflammatory reaction could be induced in chronic stage.