The clinical guidelines for the treatment of anal fistula (2006 edition) (commonly known as the “Zhuhai standard”) were developed by the Chinese Society of Traditional Chinese Medicine, Chinese Society of Surgery, Colorectal and Anal Surgery Group, and the Chinese Society of Integrative Medicine, Colorectal and Anal Diseases Committee. 1.Low anal fistula Low simple anal fistula: the internal opening is in the anal fossa, and only one fistula passes through the subcutaneous or superficial part of the external sphincter and communicates with the skin. Low complex anal fistula: there are more than two internal or external ports, and the fistula tract passes through the subcutaneous and superficial part of the external sphincter. 2, high anal fistula high simple anal fistula: internal mouth in the anal fossa, there is only one fistula tract, walking above the deep layer of the external sphincter. High complex anal fistula: there are more than two external ports, connected to the internal port through the fistula or with a branched cavity, and its supervisor passes above the deep layer of the external sphincter. The classification of fistulas depends on the relationship between the fistula and the anal sphincter and is divided into: intersphincteric, trans-sphincteric, supra-sphincteric, and extrasphincteric. When the fistula crosses more than 30-50% of the external sphincter (high intersphincter, supra-sphincter, external sphincter), female anterior fistula, multiple fistulas, recurrent fistulas, or fistulas with anal incontinence, or fistulas that may cause anal incontinence after treatment are considered complex anal fistulas.