Abstract: Objective To investigate the safety and clinical efficacy of narrow band imaging(NBI) combined with green laser in the treatment of non-muscle invasive bladder tumor(NMIBC).
Methods The data of 63 patients with NMIBC who were diagnosed in our hospital from March 2015 to May 2018 and underwent green laser surgery and were followed up for 2 years were retrospectively analyzed.According operation method they were divided into 2 groups:NBI group(33 cases) received NBI combined with green laser surgery and WLI group(30 cases) received green laser surgery under WLI(white light imaging).The number of pathological changes found in the operation,the number of pathological specimens obtained,pathological results,postoperative indwelling catheter time,postoperative hospital stay,intraoperative and postoperative complications,postoperative recurrence rate within 2 years were compared between the two groups.
Results The number of lesions per capita and the total number of pathological specimens obtained in NBI group were more than those in WLI group(2.4±1.4/person,95 cases vs 1.3±0.5/person,61 cases,P<0.01).Low grade urothelial carcinoma was the main pathological result.The operation time of WLI group was shorter than that of NBI group[(29.4±17.9)min vs (49.1±21.8)min,P<0.01].There was no significant difference in indwelling catheter time and postoperative hospital stay between two groups(P>0.05).The incidence of complications in group NBI was higher than that in group WLI(18.2% vs 16.7%,P<0.01),and the main complication was bladder spasm.The 2-year recurrence rate of group NBI was significantly lower than group WLI(3.0% vs 10.0%,P<0.01),and the recurrence case in group NBI was not in situ recurrence after 1 year.
Conclusion NBI combined with green laser in the treatment of NMIBC is safe and effective.It can reduce the recurrence rate,and simple to operate.It is worthy of further clinical research and promotion.

Key words: narrow band imaging, white light imaging, green laser, non-muscle invasive bladder cancer