实验性肝脏撞击伤的伤情特点及应用^(99m)TcO_4^-标记红细胞ECT进行诊断的价值

Characteristics of experimental model of liver impact injury in rabbits and diagnosis value of labelling erythrocyte ECT with ^(99m) TcO_4

目的 探讨应用９９ｍ 锝Ｏ４（ ９９ｍ ＴｃＯ４） 标记红细胞单光子发射计算机体层摄影术（ＥＣＴ）对实验性肝脏创伤的诊断价值。 方法 采用钢球自由落体复制家兔肝脏撞击伤模型，按氯化亚锡２０ μｇｋｇ 体重的量从兔耳缘静脉注入亚锡焦磷酸盐溶液，３０ ｍｉｎ 后再注入３７ ＭＢｑ ９９ｍ ＴｃＯ４ ，使其在体内与红细胞结合，１０ ｍｉｎ 后ＥＣＴ开始静态采集观察核素显像。 结果 肝脏破裂伤的发生率达１００ ％ ，肝损伤的主要类型有肝包膜下血肿、肝实质裂伤、肝中心型破裂及肝实质广泛破裂。影像变化主要表现为：（１） 肝膈面出现局限性增强区；（２） 肝影中部放射性浓聚明显增强，且范围较大或肝影向下扩大；（３）腹腔内片状或大片状异常放射性分布出现。同时，合并心肺损伤的影像与正常影像比较均表现为放射性浓聚增强。 结论 ＥＣＴ对肝创伤合并心肺损伤有较好的诊断参考价值。放射性核素分布变化与肝损伤类型有较好的相关性。

Objective To explore the diagnosis value of erythrocyte emission computed tomography (ECT) labelling with 99m TcO 4 on experimental liver impact injury. Methods The model of liver impact injury in rabbits was established with a steel ball falling down to the xiphoid process of animals. The rabbits were injected through the aural vein with stannous pyrophosphate based on the dosage of stannous chloride at 20 μg/kg.Thirty minutes later, 37 MBq 99m TcO 4 was injected to combine with the erythrocytes. Static and dynamic nuclein images were conducted by ECT 10 minutes later. Results Hepatic rupture occurred in all rabbits.The types of liver injury were subcapsular hematoma, parenchymal rupture, central rupture and the extensive parenchymal rupture of the liver. The images showed the following changes: (1) Limited enhancement region emerged in the hepatophrenic plain; (2) Significantly increased radioactive concentration in the middle of liver image in a large area or an expansion towards the lower part;(3) Sheet or large sheet abnormal radioactive regions in the abdominal cavity. Compared with normal image, the image of cardiac and pulmonary injuries in these regions exhibited increased radioactive concentration. Conclusions ECT is fairly valuable to diagnose the liver impact injury and cardiac and pulmonary injury. The changes in distribution of radioactive nuclide are correlated with the types of liver injury.