Objective To investigate the effect of anal internal sphincter lateral incision with small needle knife on the patients with severe mixed hemorrhoids

and to explore the effect on vascular endothelial growth factor.Methods A total of 112 patients with severe mixed hemorrhoids admitted to our hospital from November 2017 to November 2018 were selected and divided into the control group and the observation group according to surgical methods

with 56 cases in each group. Both of the two groups were treated with external stripping and internal ligation.The control group was supplemented by open internal sphincter lateral incision，and the observation group was supplemented by small needle knife lateral incision.Results There was no significant difference in VEGF level between the two groups before surgery (P>0.05).The VEGF level of the two groups were increased after operation，and the observation group was significantly higher than the control group (P<0.05).The clinical surgical indicators such as peroperative volume，operation time，wound healing time and hospitalization in the observation group were better than those in the control group (P<0.05).The VAS score of the observation group was lower than that of the control group，and the first defecation time of the observation group was shorter than that of the control group(P<0.05).The clinical treatment effect of the observation group was significantly better than that of the control group (P<0.05).Conclusion Anal internal sphincter lateral incision with small needle knife for the patients with severe mixed hemorrhoids is effective，and it is conducive to the prognosis of patients with less pain and complications.