单极电凝对胆管热损伤组织病理学改变的实验研究

Histopathological study of bile duct injury after electrocoagulation in rabbits

目的探讨胆管电凝损伤的组织学病理改变特征。方法将中国家兔随机分为5组,每组各6只。对照组常规手术器械分离胆管后取材,胆管电凝损伤后0、3、5和7 d分别取材,标本用10%甲醛固定,经石蜡包埋、切片和HE染色,光镜下观察胆管电灼伤的组织病理学改变。结果对照组正常胆管壁结构,电凝伤后0 d可见胆管壁电凝处胆管壁组织大片气化坏死,气化区管壁结构消失、肌层断裂、黏膜消失;损伤后3 d胆管病变部位可见全层炎性坏死,坏死底部炎性肉芽组织及纤维组织增生,炎性细胞浸润明显;损伤后5 d和7 d胆管壁损伤改变特征基本同第3天,但全层纤维组织增生明显,管壁明显增厚。损伤范围平均(4.11±0.28)mm。结论电凝损伤胆管壁全层,范围超出电凝区,病理改变进程主要由细胞凝固坏死,炎性坏死,纤维组织增生和管壁纤维性增厚组成。手术修复或吻合时应注意判断和处理失活的胆管壁组织。

Objective To investigate the histomorphological changes on the bile duct of rabbit after electrocoagulation injury. Methods 30 rabbits were randomized into control group, post injury day（ PID ） 0 group, PID 3 group, PID 5 group and PID 7 group. The bile ducts were only dissected with scissors and then harvested in control group. After electrocoagulation to bile ducts, the fragments of injuried ducts were harvested on PID0, PID3, PID5 and PID7 respectively. All the samples were fixed in 10% formalin, embedded with paraffins, sliced and then stained with HE. The alterations of tissue microstructures on the bile ducts were observed under light microscopy. Results Nor mal microstructures were observed in control group. In PID0 group, severe coagulative necrosis occurred in the whole layers of the injury position of bile ducts and the normal microstrutures of bile ducts were disappeared. In PID3 group, necrosis still existed with inflammatory tissue and fibroblast hyperplasia. The severe inflammatory cell infiltration were observed in the lesions. In PID5 and PID7 groups, nearly the same histomorphological changes as that in PID3 were found, but the fibroblast hyperplasia on the whole layers of the injuried ducts were more and more obvious and the wall thickness happened. The average thermal injury size was 4.11±0.28 mm in each lesion. Conclusion Electrocoagulation causes severe thermal injury to bile duct. The injury region is bigger than that seen by naked eye. The typical histological alterations include tissue coagulative necrosis, inflammatory cell infiltration, fibroblast hyperplasia and wall thickness. It is suggested that it is important to identify the lesion size and make the reasonable management to the injury tissues during the procedures of repair or anastomosis for the injuried bile duct.