Radiopaque Health Dictionary

A diagnostic technique in which the interior of a damaged joint is X-rayed after injection of a radiopaque solution.

It is being replaced by MRI, ultrasound scanning, and arthroscopy.... arthrography

An element essential for formation of the thyroid hormones, triiodothyronine (T3) and thyroxine (T4), which control the rate of metabolism (internal chemistry) and growth and development. Dietary shortage may lead to goitre or hypothyroidism. Deficiency in the newborn can, if left untreated, lead to cretinism. Shortages are very rare in developed countries due to bread and table salt being fortified with iodide or iodate. Radioactive iodine is sometimes used to reduce thyroid gland activity in cases of thyrotoxicosis and in the treatment of thyroid cancer. Iodine compounds are used as antiseptics, in radiopaque contrast media in some X-ray procedures (see imaging techniques), and in some cough remedies.... iodine

A diagnostic test in which a fine, sterile catheter is introduced into the heart via a blood vessel. It is used to diagnose and assess the extent of congenital heart disease (see heart disease, congenital) and coronary artery disease, and to diagnose and treat some disorders of the heart valves (see valvuloplasty). During the procedure, the pressure within the heart’s chambers can be measured, samples of blood and tissue can be taken, and a radiopaque substance can be injected to allow the heart’s cavities to be X-rayed.... catheterization, cardiac

The examination of the urethra and bladder using a cystoscope inserted up the urethra. A cystoscope is a rigid metal or flexible fibre-optic viewing instrument, sometimes with a camera at the tip (see endoscopy). Cystoscopy is used to inspect the bladder for calculi, bladder tumours, and sites of bleeding and infection, and to obtain urine samples from the ureters to look for infection or tumour cells. Radiopaque dye may be injected into the ureters via the cystoscope during the X-ray procedure of retrograde pyelography (see urography).

Treatment, including removal of bladder tumours or calculi and insertion of stents (narrow tubes) into a ureter to relieve an obstruction, can all be performed via the cystoscope.... cystoscopy

An X-ray procedure in which a dye (radiopaque contrast medium) is introduced into the cavity of the uterus via the cervix to make the uterus and fallopian tubes visible on X-rays. Hysterosalpingography is used to investigate infertility.... hysterosalpingography

Imaging of the pancreas or its ducts using CT scanning, MRI, ultrasound scanning, X-rays (following injection of a radiopaque contrast medium into the pancreatic ducts during exploratory surgery), or with ERCP.... pancreatography

The obtaining of X-ray images of veins that have been injected with a radiopaque substance. An alternative name is venography.... phlebography

n. imaging of blood vessels (see also coronary angiography; lymphangiography). In the older form of angiography X-ray imaging was carried out after injection of *radiopaque contrast medium and *digital subtraction applied to enhance visualization. The use of X-rays has now been largely replaced by methods using MRI or CT scanners. Magnetic resonance angiography (MRA) can be performed with (contrast-enhanced) or without (noncontrast) injection of a magnetic resonance contrast agent (see contrast medium). Contrast-enhanced MRA will show the vessels better. These images can be reconstructed in two or three dimensions. Computerized tomographic angiography (CTA) uses a radiographic contrast agent, usually injected into a vein, to increase the visibility of the blood vessels. Fluorescein angiography is a common method of investigation in ophthalmology. *Fluorescein sodium is injected into a vein in the arm, from which it circulates throughout the body. Light of an appropriate wavelength is shone into the eye, causing the dye in the retinal blood vessels to fluoresce. This allows the circulation through the retinal blood vessels to be observed and photographed. Indocyanine green (ICG) angiography uses indocyanine green dye, which fluoresces in infrared light. It is valuable in assessing circulation in the deeper layers of the *fundus.... angiography

n. X-ray examination of the bronchial tree after it has been made visible by the injection of *radiopaque dye or contrast medium. It was used particularly in the diagnosis of *bronchiectasis, but has now been largely superseded by CT scanning.... bronchography

n. a radiological examination of the erectile tissue of the penis (see corpus cavernosum) that entails the infusion of *radiopaque contrast medium into the corpora cavernosa via a small butterfly needle. The contrast medium flow rate needed to maintain erection can be measured, and radiographs taken during the procedure give information regarding any abnormality of the veins draining the penis. It is mostly used in the evaluation of erectile dysfunction. Cavernosography can also be carried out with ultrasound and ultrasound contrast medium.... cavernosography

n. X-ray examination of the gall bladder. In oral cholecystography a radiopaque contrast agent is administered by mouth, absorbed by the intestine, and excreted into bile, which is then concentrated in the gall bladder. An X-ray image (cholecystogram) may now be taken. As a technique to demonstrate the presence of gallstones, this has been replaced by ultrasound scanning. However, cholecystography is still sometimes used to look for any leakage or obstruction to drainage after surgery; in this case, the contrast medium is administered directly by catheter.... cholecystography

n. imaging of a *fistula. X-rays can be used to visualize the fistula after injection of a radiopaque *contrast medium, usually through an opening in the skin after inserting a catheter, to see the extent of a fistula and the structures with which it communicates. In *haemodialysis patients, contrast is injected through a needle into the vessels around the surgical fistula to look for blockages or narrowings that are compromising flow. *Magnetic resonance imaging is the procedure of choice for examining fistulae around the rectum and anus.... fistulography

a radiological technique used to diagnose conditions of the large bowel using the combination of X-ray imaging and radiopaque contrast (barium sulphate). Prior bowel cleansing is usually required with a colonic cleansing preparation. A large-bore tube with a balloon is inserted into the rectum and through this the barium is delivered to the caecum. The balloon is inflated in the rectum to prevent leakage of barium outside. In *double contrast studies, air is passed through the catheter to distend the colon. A series of radiographs are taken after barium has coated the colon, and the patient may be asked to change position to ensure that the whole bowel is delineated. Barium enema is used to identify colonic polyps, colorectal cancer, and diverticular disease. However, its role has been largely taken over by *colonoscopy which enables additional mucosal sampling and therapeutic intervention.... barium enema

a radiological technique used to assess the anatomy and function of the upper gastrointestinal tract. The patient swallows radiopaque contrast (barium sulphate), which coats the mucosal surfaces of the oesophagus, stomach, and duodenum. The descent of the barium is charted by a series of radiographs. Gas-forming agents (such as sodium bicarbonate) may be given to aid gastric distension and improve the quality of the images. This can be used to diagnose disorders of oesophageal motor function, tumours, peptic ulcers, hiatus *hernias, and *gastro-oesophageal reflux disease. Many indications for this examination have been replaced by the use of an endoscope.... barium swallow and meal

n. imaging of the bile ducts in order to demonstrate congenital anatomical abnormalities (such as biliary atresia), biliary diseases, and the presence of gallstones or strictures. It may be combined with imaging of the pancreatic duct (cholangiopancreatography), as in endoscopic retrograde cholangiopancreatography (see ERCP). Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive *magnetic resonance imaging technique that has largely superseded ERCP for diagnostic purposes. ERCP following MRCP is used for therapeutic intervention. In operative (or on-table) cholangiography, a radiopaque *contrast medium is injected into the bile ducts during *cholecystectomy, to ensure that there are no remaining gallstones in the ducts. Percutaneous transhepatic cholangiography (PTC) is an invasive technique in which a catheter is manipulated under direct fluoroscopic guidance through the anterior abdominal wall, across the liver, and into a bile duct; contrast solution is injected to outline the bile ducts. Using a *Seldinger technique, drains or stents can be placed to treat infection or malignant strictures. T-tube cholangiography involves the postoperative injection of radiopaque contrast material via a drain (T-tube) left in the main bile duct after cholecystectomy.... cholangiography

weakness or paralysis of the shoulder and arm usually caused by injury to the upper roots of the *brachial plexus during traumatic childbirth. This may happen if, during a difficult delivery, excess traction applied to the head damages the fifth and sixth cervical roots of the spinal cord. The muscles of the shoulder and the flexors of the elbow are paralysed and the arm hangs at the side internally rotated at the shoulder with the forearm pronated (waiter’s-tip deformity). Recovery may be spontaneous, but in some cases nerve grafts or muscle transfers are required. [W. H. Erb (1840–1921), German neurologist]

ERCP (endoscopic retrograde cholangiopancreatography) the technique in which a catheter is passed through a *duodenoscope into the *ampulla of Vater of the common bile duct and injected with a radiopaque medium to outline the pancreatic duct and bile ducts radiologically. Magnetic resonance cholangiopancreatography (MRCP; see cholangiography) is often used to diagnose biliary and pancreatic disease followed by ERCP for diagnostic confirmation and therapeutic intervention. ERCP facilitates the removal of gallstones from the common bile duct, biopsy of lesions, and insertion of biliary *stents. See also papillotomy.... erb’s palsy

n. radiological examination of the uterus and Fallopian tubes. A radiopaque contrast material is injected through a catheter placed in the uterine cavity and the flow is then observed with X-rays. The technique is used to look for patency of the Fallopian tubes in cases of infertility, or for any uterine anomalies or mass. See also sonohysterography.... hysterosalphingography

(IVU) X-ray imaging of the urinary tract following the injection into a vein of a radiopaque *contrast medium. This material is concentrated and excreted by the kidneys, and the IVU reveals the ureters and bladder. An IVU provides information about kidney function and may reveal the presence of stones, tumours, obstructions, or anatomical abnormalities in the urinary tract. See also pyelography.... intravenous urography

n. a radiological examination of any tube or line placed into any organ. A radiopaque contrast material is injected through the line and the flow is observed with X-rays, to look for any leakage or blockage of the tubing or the organ it is placed in.... linogram

n. *radiography of one or both Fallopian tubes after a *radiopaque substance has been introduced into them via an injection into the uterus. Standardized selective salpingography enables occluded tubes, visualized by salpingography, to be restored to patency by means of tubal *catheterization.... salpingography

n. a pad of absorbent material (such as cotton), sometimes attached to a stick or wire, used for cleaning out or applying medication to wounds, operation sites, or body cavities. In operations, gauze swabs are used to clean blood from the site; such swabs are always carefully counted and contain a *radiopaque ‘tag’ to facilitate identification should it by mischance remain in the body after operation.... swab

n. a specialized method of X-ray examination to demonstrate the spinal canal that involves injection of a radiopaque contrast medium into the subarachnoid space by *lumbar puncture. The X-rays obtained are called myelograms. It is of importance in the recognition of tumours of the spinal cord and other conditions compressing the cord or the nerve roots. The former use of oil-based dyes in myelography was an occasional cause of *arachnoiditis. This complication is now avoided by the use of water-soluble contrast media. Myelography is now often combined with simultaneous CT scanning but is becoming increasingly superseded by *magnetic resonance imaging.... myelography

n. X-ray examination of the renal pelvis using *radiopaque contrast material. Anterograde pyelography is performed by puncturing the renal pelvis directly with a needle through the skin and injecting contrast material. Intravenous pyelography is usually part of an examination of the whole urinary tract (see intravenous urography). Retrograde pyelography is performed after a tube has been inserted through the bladder and up the ureter at cystoscopy. Contrast material is injected up this tube as it is withdrawn and X-ray images taken. All techniques are used to show the anatomy of the renal pelvis and its drainage, as well as to demonstrate the presence of tumours and stones.... pyelography

n. an X-ray of the urinary tract or any part of it. It is usually obtained after the intravenous injection of a radiopaque substance, as in *intravenous urography, but the contrast medium can also be introduced percutaneously or, in the case of the bladder, transurethrally (for a cystogram; see cystography).... urogram

n. radiological examination of the urinary tract. This traditionally involves the injection of radiopaque contrast material and observation of the flow with X-rays (see cystography; intravenous urography; pyelography; urethrography). In CT urography contrast is injected in the vein and CT of the urinary tract acquired when the contrast arrives there. The technique is used in *haematuria to exclude the presence of a tumour within the renal pelvis, ureter, or bladder. MR urography is used to visualize the urinary tract by *magnetic resonance imaging. An MR contrast medium is injected into a peripheral vein and passes to the kidneys and ureters, when images of thin sections can be obtained. These can be manipulated by computer to reveal the anatomy and any pathology (e.g. stones, tumours) of the imaged structures. MR urography is particularly useful in children.... urography

n. a surgical incision into the vas deferens (the duct conveying sperm from the testis). This is usually undertaken to allow catheterization of the vas and the injection of radiopaque contrast material for X-ray examination (see vasography), to test for patency of the duct in patients with *azoospermia.... vasotomy

(phlebography) n. imaging of the veins. Traditionally a *radiopaque contrast medium is injected into a vein and X-ray photographs (venograms) taken as the medium flows towards the heart. Damage, obstruction, or abnormal communication with other vessels can be demonstrated. It can be done during a CT or MRI evaluation. A common usage is in demonstrating deep vein *thrombosis in the legs. Increasingly ultrasound is being used, both with colour Doppler (see Doppler ultrasound) and *compression venography. See also angiography.... venography