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Anorectal Varices
Anorectal varices are collateral submucosal blood vessels dilated by backflow in the veins of the rectum. Typically this occurs due to portal hypertension which shunts venous blood from the portal system through the portosystemic anastomosis present at this site into the systemic venous system. This can also occur in the esophagus, causing esophageal varices, and at the level of the umbilicus, causing caput medusae. Between 44% and 78% of patients with portal hypertension get anorectal varices. Signs and symptoms Pathogenesis Blood from the superior portion of the rectum normally drains into the superior rectal vein and via the inferior mesenteric vein to the liver as part of the portal venous system. Blood from the middle and inferior portions of the rectum is drained via the middle and inferior rectal veins. In portal hypertension, venous resistance is increased within the portal venous system; when the pressure in the portal venous system increases above that of the syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastroenterology
Gastroenterology (from the Greek gastḗr- "belly", -énteron "intestine", and -logía "study of") is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometimes referred to as the ''GI tract,'' which includes the esophagus, stomach, small intestine and large intestine as well as the accessory organs of digestion which include the pancreas, gallbladder, and liver. The digestive system functions to move material through the GI tract via peristalsis, break down that material via digestion, absorb nutrients for use throughout the body, and remove waste from the body via defecation. Physicians who specialize in the medical specialty of gastroenterology are called gastroenterologists or sometimes ''GI doctors''. Some of the most common conditions managed by gastroenterologists include gastroesophageal reflux disease, gastrointestinal bleeding, irritable bowel syndrome, inflammatory bowel disease (IBD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophageal Varices
Esophageal varices are extremely Vasodilation, dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendency to develop severe bleeding which left untreated can be exsanguination, fatal. Esophageal varices are typically diagnosed through an esophagogastroduodenoscopy. Pathogenesis The upper two thirds of the esophagus are drained via the esophageal veins, which carry deoxygenated blood from the esophagus to the azygos vein, which in turn drains directly into the superior vena cava. These veins have no part in the development of esophageal varices. The lower one third of the esophagus is drained into the superficial veins lining the esophageal mucosa, which drain into the left gastric vein, which in turn drains directly into the portal vein. These superficial veins (normally only approximately 1 mm in diameter) become distended up to 1� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectal Venous Plexus
The rectal venous plexus (or hemorrhoidal plexus) is the venous plexus surrounding the rectum. It consists of an internal and an external rectal plexus. It is drained by the superior, middle, and inferior rectal veins. It forms a portosystemic (portocaval) anastomosis. This allows rectally administered medications to bypass first pass metabolism. Despite the inclusion of the term "rectal" into the name, the venous plexus is positionally, functionally, and clinically primarily related to the anal canal. Anatomy The rectal venous plexus consists of an external rectal plexus that is situated outside to the muscular wall, and an internal rectal plexus that is situated in the submucosa/deep to the mucosa of the rectum and proximal anal canal at the anorectal junction. Internal rectal plexus The internal plexus presents a series of dilated pouches which are arranged in a circle around the tube, immediately above the anal orifice, and are connected by transverse branches. The intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haemorrhoids
Hemorrhoids (or haemorrhoids), also known as piles, are vascular structures in the anal canal. In their normal state, they are cushions that help with stool control. They become a disease when swollen or inflamed; the unqualified term ''hemorrhoid'' is often used to refer to the disease. The signs and symptoms of hemorrhoids depend on the type present. Internal hemorrhoids often result in painless, bright red rectal bleeding when defecating. External hemorrhoids often result in pain and swelling in the area of the anus. If bleeding occurs, it is usually darker. Symptoms frequently get better after a few days. A skin tag may remain after the healing of an external hemorrhoid. While the exact cause of hemorrhoids remains unknown, a number of factors that increase pressure in the abdomen are believed to be involved. This may include constipation, diarrhea, and sitting on the toilet for long periods. Hemorrhoids are also more common during pregnancy. Diagnosis is made by loo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rectal Varices
Anorectal varices are collateral submucosal blood vessels dilated by backflow in the veins of the rectum. Typically this occurs due to portal hypertension which shunts venous blood from the portal system through the portosystemic anastomosis present at this site into the systemic venous system. This can also occur in the esophagus, causing esophageal varices, and at the level of the umbilicus, causing caput medusae. Between 44% and 78% of patients with portal hypertension get anorectal varices. Signs and symptoms Pathogenesis Blood from the superior portion of the rectum normally drains into the superior rectal vein and via the inferior mesenteric vein to the liver as part of the portal venous system. Blood from the middle and inferior portions of the rectum is drained via the middle and inferior rectal veins. In portal hypertension, venous resistance is increased within the portal venous system; when the pressure in the portal venous system increases above that of the sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Varicose Veins
Varicose veins, also known as varicoses, are a medical condition in which superficial veins become enlarged and twisted. Although usually just a cosmetic ailment, in some cases they cause fatigue, pain, itch, itching, and cramp, nighttime leg cramps. These veins typically develop in the legs, just under the skin. Their complications can include bleeding, ulcer (dermatology), skin ulcers, and superficial thrombophlebitis. Varices in the scrotum are known as varicocele, while those around the Human anus, anus are known as hemorrhoids. The physical, social, and psychological effects of varicose veins can lower their bearers' quality of life. Varicose veins have no specific cause. Risk factors include obesity, lack of exercise, leg trauma, and family history of the condition. They also develop more commonly during pregnancy. Occasionally they result from chronic venous insufficiency. Underlying causes include weak or damaged valves in the veins. They are typically diagnosed by examina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systemic Venous System
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek meaning ''heart'', and Latin meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Many invertebrates such as arthropods have an open circulatory system with a heart that p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Rectal Vein
The lower part of the external hemorrhoidal plexus is drained by the inferior rectal veins (or inferior hemorrhoidal veins) into the internal pudendal vein. Veins superior to the middle rectal vein in the colon and rectum drain via the portal system to the liver. Veins inferior, and including, the middle rectal vein drain into systemic circulation and are returned to the heart, bypassing the liver. Pathologies involving the Inferior rectal veins may cause lower GI bleeding. Depending on the degree of inflammation, they are given a grade level ranging from 1 through 4. Additional images File:Gray405.png, The perineum. The integument and superficial layer of superficial fascia reflected. References Veins of the torso {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Rectal Vein
The middle rectal veins (or middle hemorrhoidal vein) take origin in the hemorrhoidal plexus and receive tributaries from the bladder, prostate, and seminal vesicle. They run lateralward on the pelvic surface of the levator ani to end in the internal iliac vein The internal iliac vein (hypogastric vein) begins near the upper part of the greater sciatic foramen, passes upward behind and slightly medial to the internal iliac artery and, at the brim of the pelvis, joins with the external iliac vein to for .... Veins superior to the middle rectal vein in the colon and rectum drain via the portal system to the liver. Veins inferior, and including, the middle rectal vein drain into systemic circulation and are returned to the heart, bypassing the liver. References Veins of the torso {{circulatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portal Venous System
In the circulatory system of vertebrates, a portal venous system occurs when a capillary bed pools into another capillary bed through veins, without first going through the heart. Both capillary beds and the blood vessels that connect them are considered part of the portal venous system. Most capillary beds drain into venules and veins which then drain into the heart, not into another capillary bed. There are three portal systems, two venous: the hepatic portal system and the hypophyseal portal system; and one arterial (one capillary system between two arteries): the renal portal system. Unqualified, ''portal venous system'' usually refers to the hepatic portal system. For this reason, portal vein most commonly refers to the hepatic portal vein. The functional significance of such a system is that it transports products of one region directly to another region in relatively high concentrations. If the heart were involved in the blood circulation between those two regions, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver
The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of various proteins and various other Biochemistry, biochemicals necessary for digestion and growth. In humans, it is located in the quadrants and regions of abdomen, right upper quadrant of the abdomen, below the thoracic diaphragm, diaphragm and mostly shielded by the lower right rib cage. Its other metabolic roles include carbohydrate metabolism, the production of a number of hormones, conversion and storage of nutrients such as glucose and glycogen, and the decomposition of red blood cells. Anatomical and medical terminology often use the prefix List of medical roots, suffixes and prefixes#H, ''hepat-'' from ἡπατο-, from the Greek language, Greek word for liver, such as hepatology, and hepatitis The liver is also an accessory digestive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inferior Mesenteric Vein
In human anatomy, the inferior mesenteric vein (IMV) is a blood vessel that drains blood from the large intestine. It usually terminates when reaching the splenic vein, which goes on to form the portal vein with the superior mesenteric vein (SMV). Structure The inferior mesenteric vein merges with the splenic vein, posterior to the middle of the body of the pancreas. The splenic vein then merges with the superior mesenteric vein to form the portal vein. Tributaries Tributaries of the inferior mesenteric vein drain the large intestine, sigmoid colon and rectum. These include: * left colic vein * sigmoid veins * superior rectal vein * rectosigmoid veins Variation Anatomical variations include the inferior mesenteric vein draining into the confluence of the superior mesenteric vein ''and'' splenic vein and the inferior mesenteric vein draining in the superior mesenteric vein. Clinical significance The inferior mesenteric vein may be damaged during Abdominal surgery, surger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
