Effect of low-power Holmium laser instant cutting on ureteral stricture and tissue fibrosis
10.3760/cma.j.cn112330-20240614-00266
- VernacularTitle: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
- Author:
Yonghan PENG
1
;
Chao LI
;
Hao DONG
;
Xiaofeng GAO
Author Information
1. 海军军医大学第一附属医院泌尿外科，上海 200433
- Keywords:
Ureter;
Stricture;
Thermal injury;
Laser lithotripsy;
Animal experiment
- From:
Chinese Journal of Urology
2024;45(7):539-543
- CountryChina
- Language:Chinese
-
Abstract:
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 o'clock 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, and 3 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[ (1 645.46±277.01) μm vs. (1 976.59±222.62) μm vs. (1 841.37±189.59) μm vs. (2 055.66±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. Conclusions: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.
