The human anus from Latin anus meaning "ring", "circle"   is the external opening of the rectum. Two sphincters control the exit of feces from the body during an act of defecationwhich is the primary function of the anus. These are the internal anal sphincter and the external anal sphincterwhich are circular muscles that normally maintain constriction of the orifice and which relaxes as required by normal physiological functioning.
The anus is the opening at the end of the digestive tract where stool leaves the body. The rectum is the section of the digestive tract above the anus where stool is held before it passes out of the body through the anus. The anus is formed partly from the surface layers of the body, including the skin, and partly from the intestine.
Most anal fistulas form in reaction to an anal gland that has developed a pus-filled infection abscess. Even if your abscess drains on its own, you have about the same risk for a fistula. Certain conditions that affect your lower digestive tract or anal area may also increase your risk.
Once it's confirmed that you have anal cancer, your doctor may recommend additional tests to determine whether your cancer has spread to your lymph nodes or to other areas of your body. Your doctor uses the information from the procedures to assign your cancer a stage. The stages of anal cancer are indicated using Roman numerals ranging from 0 to IV, with the lowest stages indicating that the cancer is small and confined to the anus. By stage IV, the cancer has spread to distant areas of the body.
Anal warts are small growths that appear around and inside the anal area. The human papillomavirus HPV causes anal warts, which doctors may call condylomas. These strains are more likely to cause anal cancer.
Anal cancer is a type of cancer that forms in tissues of the anus. The anus is the opening of the rectum to the outside of the body and at the end of the GI tract. Sometimes anal cancer causes no symptoms at all.
Jump to content. An anal fissure is a tear in the lining of the lower rectum anal canal that causes pain during bowel movements. Anal fissures don't lead to more serious problems.
A skin tag is a noncancerous growth of excess skin. Skin tags that form around the anus or rectum are called anal skin tags. Anal skin tags are typically small, measuring a few millimeters or less. They may be the same color as the skin or slightly darker.
An anal fissure is a small tear or ulcer open sore in the skin just inside your anus bottom. It causes severe pain, and sometimes bleeding when you pass faeces. Anal fissures often go away by themselves with some simple self-help measures.
Anal sac disease is caused by clogging or infection of glands called anal sacs located on each side of the anus. It is the most common disease of the anal region in dogs. The anal sacs are related to the scent glands in skunks and produce a small amount of foul-smelling liquid. The liquid is normally squeezed out during defecation.