The medical definition of a parastomal hernia is a hernia formed by a fistula (stoma) that protrudes from an artificial channel adjacent to the intestine or ureter in order to divert intestinal contents or urine is called a parastomal hernia. Parastomal hernias often occur in patients with incomplete healing between the stoma channel and the viscus that penetrates the abdominal wall, and are a late complication after fistula surgery. What causes a parastomal hernia? (A) Pathogenesis The occurrence of a parastomal hernia is closely related to the patient’s systemic and local conditions. Increased postoperative abdominal pressure, malnutrition, obesity and local infection are the basis for the development of parastomal hernia, while the choice of stoma site and stoma technique are also related to the development of parastomal hernia. (2) Classification There are two ways to classify parastomal hernia: (1) true parastomal hernia: the peritoneal sac protrudes from the enlarged fascial defect, which is the most common and accounts for about 90% of parastomal hernia; (2) interstomal hernia: the fascial defect is enlarged and the intestinal loop in the abdominal cavity protrudes subcutaneously along with the intestinal loop of the stoma, which is mostly combined with prolapse; (3) subcutaneous prolapse: the fascial loop is intact and the intestinal loop is redundant and protrudes subcutaneously. (3) subcutaneous prolapse: the fascial ring is intact, but the intestinal loop is long and protrudes subcutaneously, which is a pseudohernia; (4) pseudohernia: the stoma intestinal loop prolapses due to weakness of the abdominal wall or injury to the lateral rectus abdominis muscle. There are 4 types of hernias according to their size: ① small parastomal hernia: 10 cm in diameter. What are the manifestations of parastomal hernia and how to diagnose it? It is related to the size of parastomal hernia and whether there are complications. In the early stage, there are no obvious clinical symptoms, or only a subcutaneous mass protruding outward next to the stoma, which appears during prolonged standing, walking, coughing and straining, defecation and urination, and decreases or disappears when resting or lying down; the mass will gradually increase in size. As the hernia sac expands and pulls on the abdominal wall and stoma, some patients may experience localized dull pain, swelling, fullness, indigestion, constipation, and other discomforts. Giant hernias can affect dressing and life. 1. Medical history The patient has a history of abdominal stoma (orifice) within 2 years. 2. Clinical features Parastomal swelling, or prolapse of stoma intestinal loops; abdominal pain in case of giant swelling. How should a parastomal hernia be treated? 1.Non-surgical treatment For small hernias with no obvious discomfort, lap band stoma belt can be used to apply pressure and bandage, or ring-shaped compression device can be used to fix the tissue around the stoma to prevent further herniation of internal organs. Except for those with advanced cancer (including those after palliative surgery and those with abdominal or distant metastases) and serious medical comorbidities that cannot tolerate surgery, parastomal hernia can be treated surgically. (1) In situ hernia repair and stoma displacement: For parastomal hernia with a small fascial defect, an incision can be made laterally next to the stoma to find and remove the hernia sac to restore the hernia contents, reposition the stoma, and intermittently suture the defect. For those with large defects that are difficult to repair directly, synthetic materials (prosthetic mesh) can be used to repair the defect. (2) Stoma relocation: For those who are unsatisfied with the original stoma and recurrence after in situ repair, the stoma should be relocated, another median incision should be made, a suitable location should be chosen, and the original stoma should be removed and closed through a rectus abdominis stoma.