Cholescintigraphy | |
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![]() Normal hepatobiliary scan (HIDA scan). The nuclear medicine hepatobiliary scan is clinically useful in the detection of the gallbladder disease. | |
ICD-9-CM | 92.02 |
OPS-301 code | 3-707.6 |
Cholescintigraphy or hepatobiliary scintigraphy is scintigraphy of the hepatobiliary tract, including the gallbladder and bile ducts. The image produced by this type of medical imaging, called a cholescintigram, is also known by other names depending on which radiotracer is used, such as HIDA scan, PIPIDA scan, DISIDA scan, or BrIDA scan. [1] [2] Cholescintigraphic scanning is a nuclear medicine procedure to evaluate the health and function of the gallbladder and biliary system. A radioactive tracer is injected through any accessible vein and then allowed to circulate to the liver, where it is excreted into the bile ducts and stored by the gallbladder [3] until released into the duodenum.
Use of cholescintigraphic scans as a first-line form of imaging varies depending on indication. For example for cholecystitis, cheaper and less invasive ultrasound imaging may be preferred, [4] while for bile reflux cholescintigraphy may be the first choice. [5]
In the absence of gallbladder disease, the gallbladder is visualized within 1 hour of the injection of the radioactive tracer.[ citation needed ]
If the gallbladder is not visualized within 4 hours after the injection, this indicates either cholecystitis or cystic duct obstruction, such as by cholelithiasis (gallstone formation). [6]
The investigation is usually conducted after an ultrasonographic examination of the abdominal right upper quadrant for a patient presenting with abdominal pain. If the noninvasive ultrasound examination fails to demonstrate gallstones, or other obstruction to the gallbladder or biliary tree, in an attempt to establish a cause of right upper quadrant pain, a cholescintigraphic scan can be performed as a more sensitive and specific test.[ citation needed ]
Cholescintigraphy for acute cholecystitis has sensitivity of 97%, specificity of 94%. [7] Several investigators have found the sensitivity being consistently higher than 90% though specificity has varied from 73–99%, yet compared to ultrasonography, cholescintigraphy has proven to be superior. [8] The scan is also important to differentiate between neonatal hepatitis and biliary atresia, because an early surgical intervention in form of Kasai portoenterostomy or hepatoportoenterostomy can save the life of the baby as the chance of a successful operation after 3 months seriously decreases. [9]
Cholescintigraphy is also used in diagnosis of the biliary dyskinesia.
Most radiotracers for cholescintigraphy are metal complexes of iminodiacetic acid (IDA) with a radionuclide, usually technetium-99m. This metastable isotope has a half-life of 6 hours, so batches of radiotracer must be prepared as needed using a moly cow. A widely recognized trade name for the preparation kits is TechneScan. These radiopharmaceuticals include the following: [10] [11]
Nonproprietary drug name (USP format) | Common chemical name | Acronym | Comments |
---|---|---|---|
technetium Tc 99m lidofenin | hepatobiliary iminodiacetic acid; [12] dimethyl-iminodiacetic acid [10] | HIDA | An early and widely used tracer; not used as much anymore, as others have progressively replaced it, [13] [6] but the term "HIDA scan" is sometimes used even when another tracer was involved, being treated as a catch-all synonym. |
technetium Tc 99m iprofenin | paraisopropyl-iminodiacetic acid [10] | PIPIDA | |
technetium Tc 99m disofenin | diisopropyl-iminodiacetic acid [10] | DISIDA | |
technetium Tc 99m mebrofenin | trimethylbromo-iminodiaceticacid [12] | BrIDA | |
diethyl-iminodiacetic acid [10] | EIDA | Seems to have been a laboratory tracer but never widely used clinically | |
parabutyl-iminodiacetic acid [10] | PBIDA | Seems to have been a laboratory tracer but never widely used clinically | |
BIDA [14] | Seems to have been a laboratory tracer but never widely used clinically | ||
DIDA [14] | Seems to have been a laboratory tracer but never widely used clinically | ||
The word cholescintigraphy ( /ˌkoʊliˌsɪnˈtɪɡrəfi/ ) uses combining forms of chole- + scinti(llation) + -graphy , most literally "bile + flash + recording".
Bile, or gall, is a yellow-green fluid produced by the liver of most vertebrates that aids the digestion of lipids in the small intestine. In humans, bile is primarily composed of water, produced continuously by the liver, and stored and concentrated in the gallbladder. After a human eats, this stored bile is discharged into the first section of their small intestine.
In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, although the structure and position of the gallbladder can vary significantly among animal species. It receives and stores bile, produced by the liver, via the common hepatic duct, and releases it via the common bile duct into the duodenum, where the bile helps in the digestion of fats.
A gallstone is a stone formed within the gallbladder from precipitated bile components. The term cholelithiasis may refer to the presence of gallstones or to any disease caused by gallstones, and choledocholithiasis refers to the presence of migrated gallstones within bile ducts.
Cholecystitis is inflammation of the gallbladder. Symptoms include right upper abdominal pain, pain in the right shoulder, nausea, vomiting, and occasionally fever. Often gallbladder attacks precede acute cholecystitis. The pain lasts longer in cholecystitis than in a typical gallbladder attack. Without appropriate treatment, recurrent episodes of cholecystitis are common. Complications of acute cholecystitis include gallstone pancreatitis, common bile duct stones, or inflammation of the common bile duct.
Cholecystectomy is the surgical removal of the gallbladder. Cholecystectomy is a common treatment of symptomatic gallstones and other gallbladder conditions. In 2011, cholecystectomy was the eighth most common operating room procedure performed in hospitals in the United States. Cholecystectomy can be performed either laparoscopically, or via an open surgical technique.
Scintigraphy, also known as a gamma scan, is a diagnostic test in nuclear medicine, where radioisotopes attached to drugs that travel to a specific organ or tissue (radiopharmaceuticals) are taken internally and the emitted gamma radiation is captured by external detectors to form two-dimensional images in a similar process to the capture of x-ray images. In contrast, SPECT and positron emission tomography (PET) form 3-dimensional images and are therefore classified as separate techniques from scintigraphy, although they also use gamma cameras to detect internal radiation. Scintigraphy is unlike a diagnostic X-ray where external radiation is passed through the body to form an image.
Courvoisier's principle states that a painless palpably enlarged gallbladder accompanied with mild jaundice is unlikely to be caused by gallstones. Usually, the term is used to describe the physical examination finding of the right-upper quadrant of the abdomen. This sign implicates possible malignancy of the gallbladder or pancreas and the swelling is unlikely due to gallstones.
Gastrointestinal diseases refer to diseases involving the gastrointestinal tract, namely the esophagus, stomach, small intestine, large intestine and rectum, and the accessory organs of digestion, the liver, gallbladder, and pancreas.
Common bile duct stone, also known as choledocholithiasis, is the presence of gallstones in the common bile duct (CBD). This condition can cause jaundice and liver cell damage. Treatments include choledocholithotomy and endoscopic retrograde cholangiopancreatography (ERCP).
Gallbladder cancer is a relatively uncommon cancer, with an incidence of fewer than 2 cases per 100,000 people per year in the United States. It is particularly common in central and South America, central and eastern Europe, Japan and northern India; it is also common in certain ethnic groups e.g. Native American Indians and Hispanics. If it is diagnosed early enough, it can be cured by removing the gallbladder, part of the liver and associated lymph nodes. Most often it is found after symptoms such as abdominal pain, jaundice and vomiting occur, and it has spread to other organs such as the liver.
Radioisotope renography is a form of medical imaging of the kidneys that uses radiolabelling. A renogram, which may also be known as a MAG3 scan, allows a nuclear medicine physician or a radiologist to visualize the kidneys and learn more about how they are functioning. MAG3 is an acronym for mercapto acetyl tri glycine, a compound that is chelated with a radioactive element – technetium-99m.
Ascending cholangitis, also known as acute cholangitis or simply cholangitis, is inflammation of the bile duct, usually caused by bacteria ascending from its junction with the duodenum. It tends to occur if the bile duct is already partially obstructed by gallstones.
Biliary colic, also known as symptomatic cholelithiasis, a gallbladder attack or gallstone attack, is when a colic occurs due to a gallstone temporarily blocking the cystic duct. Typically, the pain is in the right upper part of the abdomen, and can be severe. Pain usually lasts from 15 minutes to a few hours. Often, it occurs after eating a heavy meal, or during the night. Repeated attacks are common.
The biliary tract refers to the liver, gallbladder and bile ducts, and how they work together to make, store and secrete bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids and conjugated bilirubin. Some components are synthesized by hepatocytes ; the rest are extracted from the blood by the liver.
Gallbladder diseases are diseases involving the gallbladder and is closely linked to biliary disease, with the most common cause being gallstones (cholelithiasis).
Biliary dyskinesia is a disorder of some component of biliary part of the digestive system in which bile cannot physically move in the proper direction through the tubular biliary tract. It most commonly involves abnormal biliary tract peristalsis muscular coordination within the gallbladder in response to dietary stimulation of that organ to squirt the liquid bile through the common bile duct into the duodenum. Ineffective peristaltic contraction of that structure produces postprandial right upper abdominal pain (cholecystodynia) and almost no other problem. When the dyskinesia is localized at the biliary outlet into the duodenum just as increased tonus of that outlet sphincter of Oddi, the backed-up bile can cause pancreatic injury with abdominal pain more toward the upper left side. In general, biliary dyskinesia is the disturbance in the coordination of peristaltic contraction of the biliary ducts, and/or reduction in the speed of emptying of the biliary tree into the duodenum.
Sphincter of Oddi dysfunction refers to a group of functional disorders leading to abdominal pain due to dysfunction of the Sphincter of Oddi: functional biliary sphincter of Oddi and functional pancreatic sphincter of Oddi disorder. The sphincter of Oddi is a sphincter muscle, a circular band of muscle at the bottom of the biliary tree which controls the flow of pancreatic juices and bile into the second part of the duodenum. The pathogenesis of this condition is recognized to encompass stenosis or dyskinesia of the sphincter of Oddi ; consequently the terms biliary dyskinesia, papillary stenosis, and postcholecystectomy syndrome have all been used to describe this condition. Both stenosis and dyskinesia can obstruct flow through the sphincter of Oddi and can therefore cause retention of bile in the biliary tree and pancreatic juice in the pancreatic duct.
A DMSA scan is a radionuclide scan that uses dimercaptosuccinic acid (DMSA) in assessing renal morphology, structure and function. Radioactive technetium-99m is combined with DMSA and injected into a patient, followed by imaging with a gamma camera after 2-3 hours. A DMSA scan is usually static imaging, while other radiotracers like DTPA and MAG3 are usually used for dynamic imaging to assess renal excretion.
Technetium (99mTc) mebrofenin is a diagnostic radiopharmaceutical used for imaging of the liver and the gallbladder. Under the brand name Choletec it is available from Bracco Diagnostic. Supplied as a sterile kit of mebrofenin and dehydrated stannous fluoride. The vial is reconstituted with 1 to 5 mL up to 3.7 gigabecquerels (100 mCi) of sodium pertechnetate solution to form the final radio labeled 99mTc mebrofenin.
Biliary sludge refers to a viscous mixture of small particles derived from bile. These sediments consist of cholesterol crystals, calcium salts, calcium bilirubinate, mucin, and other materials.
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