rectum It is the last part of the large intestine that ends at the anus.
The average length of the human rectum ranges from 10 to 15 cm. Its diameter can be compared to the starting diameter of the sigmoid colon (the part of the large intestine closest to the rectum). However, it becomes larger near the anus, forming the rectal ampulla.
An important role of the rectal ampulla is to act as a temporary reservoir for feces. The expansion of the rectal wall causes stretch receptors within the rectal wall to stimulate the urge to defecate. Delayed defecation process can lead to constipation. Once the storage site is full, intrarectal pressure causes the walls of the anal canal to dilate and dilate. As a result, fecal matter enters the canal.
A rectal exam may be done to diagnose certain disorders. Certain types of cancer may be diagnosed by doing a rectal endoscopy. Endoscopy is a procedure in which a doctor uses an endoscope (a small, flexible tube with a camera and light) to examine areas inside the body. Temperature can also be taken from the rectal area. For infants and toddlers, this is the most accurate way to measure actual body temperature.