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Radiocontrast Agent
Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography (contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically iodine, or more rarely barium sulfate. The contrast agents absorb external X-rays, resulting in decreased exposure on the X-ray detector. This is different from radiopharmaceuticals used in nuclear medicine which emit radiation. Magnetic resonance imaging (MRI) functions through different principles and thus MRI contrast agents have a different mode of action. These compounds work by altering the magnetic properties of nearby hydrogen nuclei. Types and uses Radiocontrast agents used in X-ray examinations can be grouped in positive (iodinated agents, barium sulfate), and negative agents (air, carbon dioxide, methylcellulose). Iodine (circulatory system) Iodinated contrast contains iodine. It is the main type of radiocontrast used for intra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ranging from 10 Nanometre, nanometers to 10 Picometre, picometers, corresponding to frequency, frequencies in the range of 30 Hertz, petahertz to 30 Hertz, exahertz ( to ) and photon energies in the range of 100 electronvolt, eV to 100 keV, respectively. X-rays were discovered in 1895 in science, 1895 by the German scientist Wilhelm Röntgen, Wilhelm Conrad Röntgen, who named it ''X-radiation'' to signify an unknown type of radiation.Novelline, Robert (1997). ''Squire's Fundamentals of Radiology''. Harvard University Press. 5th edition. . X-rays can penetrate many solid substances such as construction materials and living tissue, so X-ray radiography is widely used in medical diagnostics (e.g., checking for Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiography
Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is performed by injecting a radio-opaque contrast agent into the blood vessel and imaging using X-ray based techniques such as fluoroscopy. With time-of-flight (TOF) magnetic resonance it is no longer necessary to use a contrast. The word itself comes from the Greek words ἀνγεῖον ''angeion'' 'vessel' and γράφειν ''graphein'' 'to write, record'. The film or image of the blood vessels is called an ''angiograph'', or more commonly an ''angiogram''. Though the word can describe both an arteriogram and a venogram, in everyday usage the terms angiogram and arteriogram are often used synonymously, whereas the term venogram is used more precisely. The term angiography has been applied to radionuclide angiography and newer vascular ima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barium Sulfate Suspension
Barium sulfate suspension, often simply called barium, is a contrast agent used during X-rays. Specifically it is used to improve visualization of the gastrointestinal tract (esophagus, stomach, intestines) on radiography, plain X-ray or computed tomography. It is taken by mouth or used rectal administration, rectally. Side effects include constipation, diarrhea, appendicitis, and if inhaled pneumonitis, inflammation of the lungs. It is not recommended in people with intestinal perforation or bowel obstruction. Allergic reactions are rare. The use of barium during pregnancy is safe for the baby; however, X-rays may result in harm. Barium sulfate suspension (chemistry), suspension is typically made by mixing barium sulfate powder with water. It is a non-iodinated contrast media. Barium sulfate has been known since the Middle Ages. In the United States it had come into common medical use by 1910. It is on the WHO Model List of Essential Medicines, World Health Organization's L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lower Gastrointestinal Series
A lower gastrointestinal series is a medical procedure used to examine and diagnose problems with the human colon of the large intestine. Radiographs (X-ray pictures) are taken while barium sulfate, a radiocontrast agent, fills the colon via an enema through the rectum. The term barium enema usually refers to a lower gastrointestinal series, although enteroclysis (an upper gastrointestinal series) is often called a small bowel barium enema. Purpose For any suspected large bowel disease, colonoscopy is the investigation of choice because tissue sample can be taken for investigation. Virtual colonoscopy (also known as CT colonography) is another preferred investigation, provided that facilities and expertise are available. Virtual colonoscopy also avoids the risk of total blockage of any stricture in the large bowel due to barium impaction. Some conditions are absolutely contraindicated for barium enema namely: toxic megacolon, pseudomembranous colitis, and recent histor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Gastrointestinal Series
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. De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrointestinal Tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascular system. The GI tract contains all the major organ (biology), organs of the digestive system, in humans and other animals, including the esophagus, stomach, and intestines. Food taken in through the mouth is digestion, digested to extract nutrients and absorb energy, and the waste expelled at the anus as feces. ''Gastrointestinal'' is an adjective meaning of or pertaining to the stomach and intestines. Nephrozoa, Most animals have a "through-gut" or complete digestive tract. Exceptions are more primitive ones: sponges have small pores (ostium (sponges), ostia) throughout their body for digestion and a larger dorsal pore (osculum) for excretion, comb jellies have both a ventral mouth and dorsal anal pores, while cnidarians and acoels have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barium Sulfate
Barium sulfate (or sulphate) is the inorganic compound with the chemical formula Ba SO4. It is a white crystalline solid that is odorless and insoluble in water. It occurs in nature as the mineral barite, which is the main commercial source of barium and materials prepared from it. Its opaque white appearance and its high density are exploited in its main applications.Holleman, A. F. and Wiberg, E. (2001) ''Inorganic Chemistry'', San Diego, CA. Academic Press, . Uses Drilling fluids About 80% of the world's barium sulfate production, mostly purified mineral, is consumed as a component of oil well drilling fluid. It increases the density of the fluid, increasing the hydrostatic pressure in the well and reducing the chance of a blowout. Radiocontrast agent Barium sulfate in suspension is often used medically as a radiocontrast agent for X-ray imaging and other diagnostic procedures. It is most often used in imaging of the GI tract during what is colloquially known as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Intestinal Tract, As Imaged Via Double-contrast Barium Enema
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are great apes characterized by their hairlessness, bipedalism, and high intelligence. Humans have large brains, enabling more advanced cognitive skills that facilitate successful adaptation to varied environments, development of sophisticated tools, and formation of complex social structures and civilizations. Humans are highly social, with individual humans tending to belong to a multi-layered network of distinct social groups — from families and peer groups to corporations and political states. As such, social interactions between humans have established a wide variety of values, social norms, languages, and traditions (collectively termed institutions), each of which bolsters human society. Humans are also highly curious: the desire to understand and influence phenomena has motivated humanity's development of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ioversol
Ioversol ( INN; trade name Optiray) is an organoiodine compound that is used as a contrast medium. It features both a high iodine content, as well as several hydrophilic groups. It is used in clinical diagnostics including arthrography, angiocardiography and urography Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter. Types include: * Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system. * Retrograde pyelogra .... References Radiocontrast agents Benzamides Acetanilides Iodobenzene derivatives {{pharmacology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodixanol
Iodixanol, sold under the brand name Visipaque, is an iodine-containing non-ionic radiocontrast agent. It is available as a generic medication. Medical uses The radio contrast agent is given intravenously for computed tomography (CT) imaging of the head, body, excretory urography and venography. The radiocontrast agent is also given intra-arterially for angiography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perfo ... imaging. Adverse effects About 30% of those received intravenous iodixanol injection has warmth, pain, or discomfort at the site of the injection. Other adverse effects include: taste perversion (3.5%), nausea (2.8%), and headache (2.5%). Society and culture Available forms The contrast can either be given intra-arterialy or intravenously. Veterinary uses Iodixa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iohexol
Iohexol, sold under the trade name Iodaque among others, is a contrast agent used for X-ray imaging. This includes when visualizing arteries, veins, ventricles of the brain, the urinary system, and joints, as well as during computed tomography (CT scan). It is given by mouth, injection into a vein, or into a body cavity. Side effects include vomiting, skin flushing, headache, itchiness, kidney problems, and low blood pressure. Less commonly allergic reactions or seizures may occur. Allergies to povidone-iodine or shellfish do not affect the risk of side effects more than other allergies. Use in the later part of pregnancy may cause hypothyroidism in the baby. Iohexol is an iodinated non-ionic radiocontrast agent. It is in the low osmolar family. Iohexol was approved for medical use in 1985. It is on the World Health Organization's List of Essential Medicines. Chemistry The osmolality of iohexol ranges from 322 mOsm/kg—approximately 1.1 times that of blood plasma� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urography
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter. Types include: * Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system. * Retrograde pyelogram – Any pyelogram in which contrast medium is introduced from the lower urinary tract and flows toward the kidney (i.e. in a "retrograde" direction, against the normal flow of urine). * Anterograde pyelogram (also antegrade pyelogram) – A pyelogram where a contrast medium passes from the kidneys toward the bladder, mimicking the normal flow of urine. * Gas pyelogram – A pyelogram that uses a gaseous rather than liquid contrast medium. It may also form without the injection of a gas, when gas producing micro-organisms infect the most upper parts of urinary system. Intravenous pyelogram An intravenous pyelogram (IVP), also called an intravenous urogram (IVU), is a radiological procedure used to visualize abnormalities of the urinary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
