TST, T is for tissue, S is for selection and T is for treatment, the full name is selective suprahemorrhoidal mucosal anastomosis, a new technique for the treatment of hemorrhoids developed on the basis of the PPH procedure, mainly for stage III and IV patients with mainly non-circular prolapse. Its main advantage is that the treatment is selective and the treatment can precisely remove the prolapsed part of the hemorrhoidal mucosa, maximizing the integrity of the mucosa near the dentate line and the anal cushion, preserving the normal mucosal bridge, maximizing the maintenance of the fine sensory and contractile function of the anus, and reducing the surgical trauma. although TST surgery is a new type of surgery, it does not mean that it is suitable for all patients. If the patient’s internal hemorrhoids are circumferential, they are not suitable for TST surgery, so the exact type of surgery that is more suitable needs to be determined based on the type and severity of the hemorrhoids.