The internal anal sphincter, IAS, or sphincter ani internus is a ring of smooth muscle that surrounds about 2.5–4.0 cm of the anal canal. It is about 5 mm...

anal sphincter is far more substantial than the internal anal sphincter. The proximal portion of external anal sphincter overlaps the internal anal sphincter...

primary function of the anus. These are the internal anal sphincter and the external anal sphincter, which are circular muscles that normally maintain constriction...

excrement by two muscular sphincter complexes. The anus is the aperture at the terminal portion of the anal canal. In humans, the anal canal is approximately...

some anal fissures become chronic and deep and will not heal. The most common cause of non-healing is spasming of the internal anal sphincter muscle...

anal glands or anal sacs are small glands near the anus in many mammals. They are situated in between the external anal sphincter muscle and internal...

and the end of the internal anal sphincter. The internal anal sphincter forms the walls of the anal canal. The internal anal sphincter is not under voluntary...

control the exit of feces from the body, the internal anal sphincter and external anal sphincter. The inner sphincter is involuntary and the outer is voluntary...

anal abscesses do not heal properly. Anal fistulae originate from the anal glands, which are located between the internal and external anal sphincter...

Anal sphincter muscles may refer to: External anal sphincter Internal anal sphincter This disambiguation page lists articles associated with the title...

internal sphincterotomy is an operation performed on the internal anal sphincter muscle for the treatment of chronic anal fissure. The internal anal sphincter...

involuntary relaxation of the internal anal sphincter in response to distention of the rectum. The RAIR provides the upper anal canal with the ability to...

the external anal sphincter involving less than 50% thickness 3b: greater than 50% tear of the external anal sphincter 3c: internal sphincter is torn Fourth-degree...

complications from prior anorectal surgery (especially involving the anal sphincters or hemorrhoidal vascular cushions), altered bowel habits (e.g., caused...

it forms the pyloric sphincter. in the anal canal, it forms the internal anal sphincter. In the colon, the fibres of the external longitudinal smooth muscle...

the duodenum. The orifice is surrounded by a sphincter, a band of muscle, called the pyloric sphincter. The word pylorus comes from Greek πυλωρός, via...

known respectively as the upper esophageal sphincter and the lower esophageal sphincter. These sphincters act to close the esophagus when food is not...

the desire to pass feces, a process called defecation. An internal and external anal sphincter, and resting contraction of the puborectalis, prevent leakage...

stimulation. Functional deficits of the external anal sphincter (EAS) and/or internal anal sphincter (IAS), i.e. where there is no structural defect,...

veins, toward the anal canal and the lower end of the rectum, and is distributed to the sphincter ani externus (external anal sphincter, EAS) and to the...

technique of total anal sphincter preservation in high fistula in ano, which is based on the concept of excision of intersphincteric anal gland infection...

Bauhin's valve, ileocecal eminence, valve of Varolius or colic valve) is a sphincter muscle valve that separates the small intestine and the large intestine...

atrophy of the external anal sphincter. Some authors suggest that pudendal nerve damage is the cause for pelvic floor and anal sphincter weakening, and may...

motor innervation of the hips, knees, ankles, feet, internal anal sphincter and external anal sphincter. In addition, the cauda equina extends to sensory...

nerve endings in the anal region and rectum can make anal sex pleasurable for men and women. The internal and external sphincter muscles control the opening...

muscle layer in the wall of the anal canal between the internal anal sphincter (deep to CLM) and external anal sphincter (superficial to CLM). It is continuous...

is located between the esophagus and the small intestine. The pyloric sphincter controls the passage of partially digested food (chyme) from the stomach...

causes a reflexive relaxation of the internal anal sphincter, so the contents of the rectum can move in to the anal canal. This causes the conscious feeling...

muscles, relaxation of the internal anal sphincter, and an initial contraction of the skeletal muscle of the external anal sphincter. If the urge is not acted...

stomach has a thickened portion of the inner circular layer: the pyloric sphincter. Alone among the GI tract, the stomach has a third layer of muscular layer...