Sentinel loop

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Sentinel loop
Differential diagnosis acute cholecystitis, acute pancreatis

A sentinel loop is a sign seen on a radiograph that indicates localized ileus from nearby inflammation. [1] Simply put, it is the dilation of a segment of small intestine to be differentiated from colonic cutoff sign which is a dilation of a segment of large bowel.[ citation needed ]

An isolated distended loop of bowel is seen near the site of injured viscus or inflamed organ. This loop is called a "sentinel loop." It arises from the body's efforts to localize traumatic or inflammatory lesions. The local distention of that intestinal loop is due to local paralysis and accumulation of gas in the intestinal loop. In acute pancreatitis, the sentinel loop is usually seen in left hypochondrium, while in acute cholecystitis, it is seen in the right hypochondrium. In acute appendicitis, the sentinel loop is seen in right right lower quadrant. [2]

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Small intestine Organ in the gastrointestinal tract

The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about 18 feet long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter.

Upper gastrointestinal series Radiographs used to examine abnormalities of the digestive system excluding the colon

An upper gastrointestinal series, also called a barium swallow, barium study, or barium meal, is a series of radiographs used to examine the gastrointestinal tract for abnormalities. A contrast medium, usually a radiocontrast agent such as barium sulfate mixed with water, is ingested or instilled into the gastrointestinal tract, and X-rays are used to create radiographs of the regions of interest. The barium enhances the visibility of the relevant parts of the gastrointestinal tract by coating the inside wall of the tract and appearing white on the film. This in combination with other plain radiographs allows for the imaging of parts of the upper gastrointestinal tract such as the pharynx, larynx, esophagus, stomach, and small intestine such that the inside wall lining, size, shape, contour, and patency are visible to the examiner. With fluoroscopy, it is also possible to visualize the functional movement of examined organs such as swallowing, peristalsis, or sphincter closure. Depending on the organs to be examined, barium radiographs can be classified into "barium swallow", "barium meal", "barium follow-through", and "enteroclysis". To further enhance the quality of images, air or gas is sometimes introduced into the gastrointestinal tract in addition to barium, and this procedure is called double-contrast imaging. In this case the gas is referred to as the negative contrast medium. Traditionally the images produced with barium contrast are made with plain-film radiography, but computed tomography is also used in combination with barium contrast, in which case the procedure is called "CT enterography".

Ileus Medical condition

Ileus is a disruption of the normal propulsive ability of the intestine. It can be caused by lack of peristalsis or by mechanical obstruction. The word 'ileus' is from Ancient Greek eileós. The term 'subileus' refers to a partial obstruction.

Berdon syndrome Medical condition

Berdon syndrome, also called Megacystis-microcolon-intestinal hypoperistalsis syndrome, is an autosomal recessive fatal genetic disorder affecting newborns. In a 2011 study of 227 children with the syndrome, "the oldest survivor [was] 24 years old." The Ann Arbor News reported a five year old survivor at the end of 2015.

Toxic megacolon Medical condition

Toxic megacolon is an acute form of colonic distension. It is characterized by a very dilated colon (megacolon), accompanied by abdominal distension (bloating), and sometimes fever, abdominal pain, or shock.

Colic in horses is defined as abdominal pain, but it is a clinical symptom rather than a diagnosis. The term colic can encompass all forms of gastrointestinal conditions which cause pain as well as other causes of abdominal pain not involving the gastrointestinal tract. The most common forms of colic are gastrointestinal in nature and are most often related to colonic disturbance. There are a variety of different causes of colic, some of which can prove fatal without surgical intervention. Colic surgery is usually an expensive procedure as it is major abdominal surgery, often with intensive aftercare. Among domesticated horses, colic is the leading cause of premature death. The incidence of colic in the general horse population has been estimated between 4 and 10 percent over the course of the average lifespan. Clinical signs of colic generally require treatment by a veterinarian. The conditions that cause colic can become life-threatening in a short period of time.

Intussusception (medical disorder) Medical condition

Intussusception is a medical condition in which a part of the intestine folds into the section immediately ahead of it. It typically involves the small bowel and less commonly the large bowel. Symptoms include abdominal pain which may come and go, vomiting, abdominal bloating, and bloody stool. It often results in a small bowel obstruction. Other complications may include peritonitis or bowel perforation.

Volvulus Twisting of part of the intestine, causing a bowel obstruction

A volvulus is when a loop of intestine twists around itself and the mesentery that supports it, resulting in a bowel obstruction. Symptoms include abdominal pain, abdominal bloating, vomiting, constipation, and bloody stool. Onset of symptoms may be rapid or more gradual. The mesentery may become so tightly twisted that blood flow to part of the intestine is cut off, resulting in ischemic bowel. In this situation there may be fever or significant pain when the abdomen is touched.

Intestinal malrotation is a congenital anomaly of rotation of the midgut. It occurs during the first trimester as the fetal gut undergoes a complex series of growth and development. Malrotation can lead to a dangerous complication called volvulus. Malrotation can refer to a spectrum of abnormal intestinal positioning, often including:

Necrotizing enterocolitis Medical condition

Necrotizing enterocolitis (NEC) is a devastating intestinal disease that affects premature or very low birth weight infants. Symptoms may include poor feeding, bloating, decreased activity, blood in the stool, vomiting of bile, bowel death, multiorgan failure, and even death.

Abdominal examination Physical examination of abdomen

An abdominal examination is a portion of the physical examination which a physician or nurse uses to clinically observe the abdomen of a patient for signs of disease. The physical examination typically occurs after a thorough medical history is taken, that is, after the physician asks the patient the course of their symptoms. The abdominal examination is conventionally split into four different stages: first, inspection of the patient and the visible characteristics of their abdomen. Auscultation (listening) of the abdomen with a stethoscope. Palpation of the patient's abdomen. Finally, percussion (tapping) of the patient's abdomen and abdominal organs. Depending on the need to test for specific diseases such as ascites, special tests may be performed as a part of the physical examination. An abdominal examination may be performed because the physician suspects a disease of the organs inside the abdominal cavity, or simply as a part of a complete physical examination for other conditions. In a complete physical examination, the abdominal exam classically follows the respiratory examination and cardiovascular examination.

Ogilvie syndrome Medical condition

Ogilvie syndrome is the acute dilatation of the colon in the absence of any mechanical obstruction in severely ill patients.

Ischemic colitis Medical condition

Ischemic colitis is a medical condition in which inflammation and injury of the large intestine result from inadequate blood supply. Although uncommon in the general population, ischemic colitis occurs with greater frequency in the elderly, and is the most common form of bowel ischemia. Causes of the reduced blood flow can include changes in the systemic circulation or local factors such as constriction of blood vessels or a blood clot. In most cases, no specific cause can be identified.

Distal intestinal obstruction syndrome Medical condition

Distal intestinal obstruction syndrome (DIOS) involves obstruction of the distal part of the small intestines by thickened intestinal content and occurs in about 20% of mainly adult individuals with cystic fibrosis. DIOS was previously known as meconium ileus equivalent, a name which highlights its similarity to the intestinal obstruction seen in newborn infants with cystic fibrosis. DIOS tends to occur in older individuals with pancreatic insufficiency. Individuals with DIOS may be predisposed to bowel obstruction, though it is a separate entity than true constipation.

Pneumatosis intestinalis Medical condition

Pneumatosis intestinalis is pneumatosis of an intestine, that is, gas cysts in the bowel wall. As a radiological sign it is highly suggestive for necrotizing enterocolitis. This is in contrast to gas in the intestinal lumen. In newborns, pneumatosis intestinalis is considered diagnostic for necrotizing enterocolitis, and the gas is produced by bacteria in the bowel wall. The pathogenesis of pneumatosis intestinalis is poorly understood and is likely multifactorial. PI itself is not a disease, but rather a clinical sign. In some cases, PI is an incidental finding, whereas in others, it portends a life-threatening intra-abdominal condition.

Stercoral ulcer is an ulcer of the colon due to pressure and irritation resulting from severe, prolonged constipation due to a large bowel obstruction, damage to the autonomic nervous system, or stercoral colitis. It is most commonly located in the sigmoid colon and rectum. Prolonged constipation leads to production of fecaliths, leading to possible progression into a fecaloma. These hard lumps irritate the rectum and lead to the formation of these ulcers. It results in fresh bleeding per rectum. These ulcers may be seen on imaging, such as a CT scan but are more commonly identified using endoscopy, usually a colonoscopy. Treatment modalities can include both surgical and non-surgical techniques.

Bowel infarction Injury to the intestine resulting from insufficient blood flow

Bowel infarction or gangrenous bowel represents an irreversible injury to the intestine resulting from insufficient blood flow. It is considered a medical emergency because it can quickly result in life-threatening infection and death. Any cause of bowel ischemia, the earlier reversible form of injury, may ultimately lead to infarction if uncorrected. The causes of bowel ischemia or infarction include primary vascular causes and other causes of bowel obstruction.

Intestinal ischemia Restriction of blood flow to the small intestine resulting in injury

Intestinal ischemia is a medical condition in which injury to the large or small intestine occurs due to not enough blood supply. It can come on suddenly, known as acute intestinal ischemia, or gradually, known as chronic intestinal ischemia. The acute form of the disease often presents with sudden severe abdominal pain and is associated with a high risk of death. The chronic form typically presents more gradually with abdominal pain after eating, unintentional weight loss, vomiting, and fear of eating.

Abdominal x-ray AXR or KUB

An abdominal x-ray is an x-ray of the abdomen. It is sometimes abbreviated to AXR, or KUB.

Neonatal bowel obstruction (NBO) or neonatal intestinal obstruction is the most common surgical emergency in the neonatal period. It may occur due to a variety of conditions and has an excellent outcome based on timely diagnosis and appropriate intervention.

References

  1. Brant, William E.; Helms, Clyde A. (2007). Fundamentals of Diagnostic Radiology. Lippincott Williams & Wilkins. p. 742. ISBN   9780781761352 . Retrieved 18 September 2019.
  2. Levitin, Joseph (1946). "Scout Film of the Abdomen". Radiology. Radiological Society of North America (RSNA). 47 (1): 10–29. doi:10.1148/47.1.10. ISSN   0033-8419. PMID   20992153.