About 99% of the occurrence of perianal abscess is related to anal gland infection and suppuration. Most of the normal anal glands are located between the internal and external sphincter of the anus, and the opening is located in the anal recess. When feces and bacteria enter the anal gland through the opening, they can cause anal sinusitis and anal gland inflammation, which can spread to the surrounding tissues of the anal canal and rectum, forming a perianal abscess. The gaps around the anal canal and rectum are usually filled with adipose tissue and lymphatic tissue, resulting in loose tissue. Abscesses often occur in these gaps during infection. Other causes include injuries, foreign objects, proctitis, skin diseases, etc.
Anal ultrasound (AUS) examination: For complex perianal purulent diseases, abscesses that cannot be identified clinically, anal ultrasound examination can be used to help determine the anatomical relationship between abscesses, fistulas and sphincter, and occasionally identify the internal mouth.
The main symptoms of congenital choledochal cysts in children are abdominal pain, jaundice, abdominal masses, and some are occasionally discovered during physical examinations.
The rectum is only half inside the abdominal cavity, and its front and upper sides are covered by a thin and smooth peritoneum. There is a clear depression between its front and the male bladder or female uterus, which is called a rectovesical depression in males and a rectouterine depression in females. The anterior part of the abdominal cavity is adjacent to the bladder and prostate in males