Lactase: An enzyme that converts lactose into its more digestible simple sugar components: glucose and galactose. The lactase enzyme is available in liquid form to add to milk or in tablet form to take with solid food.
Lactose-intolerance: The inability to digest lactose, the sugar primarily found in milk and dairy products.
Laparoscopy: A method of surgery that is much less invasive than traditional surgery. Tiny incisions are made to create a passageway for a special instrument called a laparoscope. This thin telescopelike instrument with a miniature video camera and light source is used to transmit images to a video monitor. The surgeon watches the video screen while performing the procedure with small instruments that pass through small tubes placed in the incisions.
Large intestine: This digestive organ is made up of the ascending (right) colon, the transverse (across) colon, the descending (left) colon, and the sigmoid (end) colon. The appendix is also part of the large intestine. The large intestine receives the liquid contents from the small intestine and absorbs the water and electrolytes from this liquid to form feces, or waste.
Laxative: Medications that increase the action of the intestines or stimulate the addition of water to the stool to increase its bulk and ease its passage. Laxatives are often prescribed to treat constipation.
Liver: One of the most complex and largest organs in the body, which performs more than 5,000 life-sustaining functions.
Liver disease: More than 100 types of liver disease have been identified including hepatitis, cirrhosis and liver tumors. When liver disease develops, the liver’s ability to perform its metabolic, detoxification and storage functions is impaired.
Magnetic resonance imaging (MRI): A test that produces images of the body without the use of X-rays. MRI uses a large magnet, radio waves and a computer to produce these images.
Mesentery: Membranous tissue which carries blood vessels and lymph glands, and attaches various organs to the abdominal wall.
Muscle transposition: A procedure in which gluteal (buttock) or gracilis (inner thigh) muscles are used to encircle and strengthen the anal canal. When the inner thigh muscle is used, pacemaker-like electrodes are implanted into the grafted muscle to train it to remain contracted. When the buttock muscle is used, the lower portion of this muscle is freed from the tailbone region and wrapped around the anus to construct a new anus. The buttock muscle transposition does not require the use of a pacemaker.