低功率钬激光瞬时切割对输尿管狭窄及组织纤维化的影响

Effect of low-power Holmium laser instant cutting on ureteral stricture and tissue fibrosis

目的探索激光瞬时切割损伤对猪输尿管狭窄及组织纤维化的影响。方法选取10头白雌猪,在双侧输尿管距肾盂输尿管连接部5、10、15、20cm处分别标记为A、B、C、D组,各组激光参数设置如下:A组0.5J×20Hz(短脉冲),B组1.0J×10Hz(短脉冲),C组0.5J×20Hz(长脉冲)和D组1.0J×10Hz(长脉冲)。每组应用钬激光进行烧灼,能量设置统一为低功率(10W),烧灼点取手术视野6点钟位置,烧灼时长约1s。术后留置双J管1个月。术后4个月处死实验猪并剖取双肾、输尿管以及膀胱标本,沿长轴开输尿管。按术中标记距离及肉眼所见记录各组烧灼点狭窄情况,截取各组烧灼点输尿管组织,行组织病理学HE染色及Masson染色,分析组织损伤及纤维化情况。结果本研究1头实验猪术中未能找到左侧输尿管开口,3头实验猪术后当天死亡。最终纳人6头猪,共12侧尿路标本进行分析,包含48个烧灼点。各烧灼点输尿管局部狭窄的发生率为64.6%(31/48),其中重度狭窄发生率为8.3%(4/48)。A、B、C、D组狭窄发生率分别为66.7%(8/12)、66.7%(8/12)66.7%(8/12)、52.5%(8/12),各组在狭窄发生率(P=1.000)及狭窄程度(P=0.075)方面的差异均无统计学意义。组织病理学分析结果显示,A、B、C、D组的组织损伤深度[(1645.46±277.01)、(1976.59±222.62)、(1841.37±189.59)、(2055.66±206.40)μm,P=0.560]及胶原纤维面积百分比[(70.22±1.75)%、(69.48±1.34)%、(68.00±2.03)%、(74.39±1.20)%,P=0.560]差异均无统计学意义。结论即使在低功率设置下,钬激光对输尿管组织的瞬时切割仍会导致较高的输尿管狭窄发生率。钬激光频率及脉冲长度选择对输尿管狭窄的发生率、组织病理损伤及纤维化程度无显著影响。

Objective To investigate the effects of Holmium laser instant cutting damage on ureteral stricture and tissue fibrosis in pigs.Methods Ten female white pigs were selected,and the bilateral ureters were marked at 5 cm,10 cm,15 cm,and 20 cm from the ureteropelvic junction(UPJ),designated as groups A,B,C,and D,respectively.The laser parameters were set as follows:Group A 0.5 J×20 Hz(short pulse),Group B 1.0 J×10 Hz(short pulse),Group C 0.5 J×20 Hz(long pulse),and Group D 1.0 J×10 Hz(long pulse).Holmium laser ablation was performed at each group with a uniform low power setting(10 W)for approximately 1 second at the 6 oclock position of the surgical field.A double J stent was placed for one month post-operation.The experimental pigs were euthanized three months after stent removal,and specimens of the kidneys,ureters,and bladder were collected.The ureters were longitudinally opened,and the stenosis at each marked ablation site was recorded and subjected to histopathological analysis.Results In this study,1 pig failed to find the left ureteral opening during the operation,and3 pigs died after operation.Six pigs with a total of 12 ureteral specimens were finally included.The incidence of local ureteral stricture at the ablation sites was 64.6%(31/48),with severe stricture occurring at 8.3%(4/48).The incidence of stricture in group A,B,C,and D were 66.7%(8/12),66.7%(8/12),66.7%(8/12),and 52.5%(8/12),respectively.There was no significant difference in the incidence(P=1.000)and degree(P=0.075)of stricture among the groups.Histopathological analysis showed no significant differences in tissue damage depth[(1645.46±277.01)μm vs.(1976.59±222.62)μm vs.(1841.37±189.59)μm vs.(2055.66±206.40)μm,P=0.560 ] and collagen fiber area percentage[(70.22±1.75)%vs.(69.48±1.34)%vs.(68.00±2.03)%vs.(74.39±1.20)%,P=0.560]among the groups.Conclusionss Even under low power settings,instant cutting of ureteral tissue by Holmium laser results in a high incidence of ureteral stricture.The frequency and pulse length of the Holmium laser have no significant effect on the incidence of ureteral stricture,histopathological damage,or the degree of fibrosis.