With the continuous improvement of modern medical diagnostic techniques, the imaging and pathological diagnosis of refractory complex anal fistulas and perianorectal abscesses has gradually received attention and improvement. From the perspective of imaging combined with pathology, the concept of the type of cystogenic anal fistula is proposed, which facilitates preoperative diagnosis, surgical route development and prognosis of recurrence, and reduces misdiagnosis and malpractice and disputes. The cause of general anal fistula is due to a decrease in body resistance and or local damage to the anal canal, and the invasion of pathogenic bacteria, which causes purulent infection of the anal glands in the anal saphenous fossa, spreading along the natural tissue spaces, forming pus cavities, and acute and chronic migration, forming fistulas and sinus tracts, called adenogenic anal fistula. In general, the internal orifice, external orifice, and fistula tract are clear, and surgical treatment is less difficult, and the recurrence rate of one operation is low. In clinical practice, we encounter a small number of anal fistula and abscess cases where primary and reoperative cure is difficult, and although excision and drainage are better, the distal or deep fistula tracts do not close well. We found that such lesions showed irregular cystic changes by preoperative MIR 3D imaging, especially the liquid area with obvious signs of cystic wall border, while the liquid border of common adenogenic anal fistula or abscess showed ambiguity; moreover, the distribution of cystic cavity along the anorectal and pelvic space could be observed by continuous picture movie animation. The cystic cavity and wall can be clearly seen during surgery, and the cystic wall feels smooth and hard to touch, with cystic separation and tendinous material. The internal port is usually located in the posterior and anterior dentate position of the anal canal, and the internal port is large and directly communicates with the cystic cavity; or the internal port cannot be found, and the cystic wall is found to have a distance of about 1 cm from the anal canal by incision; the internal port can also be found in the upper intestinal wall, which is usually the secondary port of the cystic wall infected with expansion breaking through to the rectum. Pathological examination of the cyst wall reveals epithelial tissue, suggesting that cystic masses existed before the onset of these fistulas. We believe that the cause of this type of fistula is the presence of congenital or acquired cystic lesions around the perianal rectum, which naturally expand and tend to move along the pressure and gap under the influence of pressure changes in the internal and external gaps such as defecation and sitting, with some of the cystic wall tissue spreading to the weak point of the anorectal connection (posterior and anterior middle dentition), secondary to intestinal bacterial infection, and the formation of an intracapsular abscess in the reverse direction, which increases in pressure toward the anorectal canal When the pressure increases, it ruptures into the rectum to form an anal fistula; or the infection is controlled to form a blind fistula. The pathophysiological changes are characterized by the opposite trend of development from the formation of common adenogenic fistula. The common glandular fistula is an infection of the anal glands in the anal canal that spreads to the surrounding space to form an abscess and fistula. In contrast, cystogenic fistulae are uninfected cysts that spread along the tissue space to a weak part of the rectum and then become infected, forming an intracapsular abscess and fistula, which has a harder fibrous shell and lining due to the inflammatory reaction to the infection. Moreover, it is often found clinically that patients with difficulty in defecation and discomfort of anal swelling (but no symptoms of anal fistula abscess) are found to have peri-anorectal cystic lesions on physical examination and MIR, and preoperative imaging and intraoperative exploration are similar to cystic anal fistula lesions, which also tend to have cystic tissue in the weak anorectal space, except that the cystic walls of uninfected cysts can slide and do not form a fibrous scaffold shell, making it easy to remove the cystic walls with complete peeling and postoperative Pathology: dermatomal cysts, epithelioid cysts, etc. Infection does not occur after excision, so fistulae are usually not formed.