Intestinal mucosa with necrotic ulcers

Radiation lesions of the rectum can be divided into four degrees, the second clinical manifestations are stool frequency, bloody or mucus stools, and severe stagnation. Symptoms can last for months or years. Intestinal mucosa has necrosis, ulcers, or moderate stenosis. Radiation enteritis is an intestinal complication caused by radiation therapy of pelvic, abdominal, and retroperitoneal malignant tumors. It can affect the small intestine, colon, and rectum, so it is also called radiation rectum, colon, and enteritis. Radiation sickness is generally classified into acute and chronic, according to the radiation dose of the intestine, the length of time, and the onset of the disease. It is also classified into external radiation radiation disease and internal radiation radiation disease according to the internal and external positions of the radiation source. In the early stage, intestinal mucosal cell regeneration is inhibited, and later the arteriolar wall swells and occludes, causing intestinal wall ischemia and mucosal erosion. The intestinal wall causes fibrosis in the advanced stage, the intestinal cavity is narrow or perforated, and abscesses, fistulas, and intestinal adhesions are formed in the abdominal cavity.