Objective To explore the effect of disposable electronic soft mirror and conventional repeatable soft mirror on the renal function and prostaglandin E2(PGE2),5-hydroxytryptamine(5-HT)levels in patients with upper ureteral calculi and analyze the factors influencing recurrence after retrograde intrarenal surgery(RIRS).Methods 114 patients with upper ureteral calculi from March 2022 to March 2023 were selected and randomly divided into two groups,with 57 cases forming the observation group and 57 cases forming the control group.The observation group was administrated with RIRS via disposable electronic soft mirror,while the control group accepted RIRS via conventional repeatable soft mirror.The two groups were compared in the aspect of surgical data.Patients'serum renal function indicators[blood urea nitrogen(BUN),creatinine(Cr),cystatin C(CysC)],PGE2 and 5-HT levels were tested preoperative and postoperative 24 h.Postoperative complications and recurrence were compared between the two groups after 6 months follow-up.The patients were grouped according to whether there was recurrence or not.The medical records of recurrence group and non-recurrence group were collected,and the risk factors of recurrence were analyzed statistically.Results There was no sxtatistically significant difference between the observation group and the control group in terms of surgical time,intraoperative bleeding,one-time stone removal rate,and hospital stay(P>0.05).After operation both groups saw much higher levels of BUN,Cr,CysC,PGE2 and 5-HT than they did before the operation(P<0.05),but no significant difference in the aforementioned indicators was seen between the two groups either before or after the operation(P>0.05).The incidence of complications and recurrence rate of the observation group were 3.51%and 15.79%respectively,seeing no big difference from 12.28%and 21.05%of the control group(P>0.05).The body mass index(BMI),postoperative residual calculi and urinary tract infections in the recurrence team were remarkably higher than those in the non recurrence team(P<0.05).The results of multivariate Logistic regression analysis showed that after adjusting for confounding factors such as gender,age,course of disease,maximum diameter of calculi,number of calculi,location of calculi,and surgical method,postoperative residual calculi and postoperative urinary tract infections were independent risk factors for postoperative recurrence of upper ureteral calculi after RIRS(P<0.05).Conclusion Both disposable electronic soft endoscopy and conventional repeatable soft endoscopy can achieve satisfactory results in the treatment of upper ureteral calculi,both can impact the renal function and serum PGE2,5-HT levels in patients to a certain extent,and both present a risk of recurrence after surgery.Residual postoperative calculi and postoperative urinary tract infections are independent risk factors inducing recurrence of upper ureteral calculi after RIRS.