Intravenous IV dye dye given through the vein —also known as radiocontrast media RCM —is used widely in the United States for various radiological studies, such as angiograms, X-rays, magnetic resonance imaging MRIand computed tomography CT scans. Adverse reactions to RCM are fairly common, though allergies wllergy rarer. You may be surprised to learn that allergic reactions to RCM are not truly allergic in nature, meaning that there is no allergic antibody present that causes the reaction. In general, there are two basic types of intravenous RCM used for most radiological studies. They include:. However, it's more expensive than HOCM. Despite the popular myth, having a seafood and shellfish allergy does not place you at an increased risk of having a reaction to RCM.
Structures with higher echogenicity will appear brighter on ultrasound. Once the microbubbles are in the bloodstream, ultrasound technology is xx capture differences in echogenicity between the gas in the microbubbles and the surrounding tissues of the body, producing an ultrasound dye with increased contrast. The microbubbles dissolve, usually within 10 to 15 minutes, and the gas within them is removed from the body through exhalation.
Contrast-enhanced ultrasound with microbubbles is a convenient, relatively inexpensive way to improve visualization of blood flow that does not use radiation. Raay contrast materials can be targeted or untargeted. Untargeted contrast-enhanced ultrasound —the more common method— helps diagnose certain diseases by providing evaluation of blood flow in the heart and other organs.
In targeted allefgy ultrasound, specific molecules are bound to the surface of the microbubbles. After injection, the microbubbles attach at tissue sites expressing the molecular target, leading to a local increase in the ultrasonic signal.
Contrast materials are safe drugs; adverse reactions ranging from mild 112 severe do occur but severe reactions are very uncommon. While serious allergic or other reactions to contrast allergy are ray, radiology departments are well-equipped to deal with them. Because contrast materials carry a slight risk of causing an allergic reaction or adverse reaction, you should allerfy your doctor about:. You should tell your doctor if these mild side effects of barium-sulfate contrast materials become severe or do not go away:.
A very small percentage of patients may develop a delayed reaction with a rash which can occur hours ray days after an imaging exam with an iodine-based contrast material. Most are mild, but severe rashes may require medication allergy discussion with your physician. Patients with impaired kidney renal function should be given special consideration d receiving iodine-based contrast materials by vein or artery.
Such patients are at risk for 21 contrast-induced nephropathy CINa condition in which already-impaired kidney function worsens within a few days of contrast material administration. Much of the research linking CIN with iodine-based contrast material is based on older contrast agents that are no longer used, and some recent studies have found no increased risk of CIN in patients who received iodine-based contrast material.
If you have impaired kidney function, your doctor will assess ary benefits of contrast-enhanced CT against any risks. Some conditions increase the risk of an allergic or adverse reaction to iodine-based contrast materials. These include:. Being at increased risk for an allergic or adverse reaction to contrast material does not necessarily mean a patient cannot undergo an imaging exam with contrast materials.
Medications dye de given before the contrast material is administered to lessen the risk of an aplergy reaction in susceptible patients. A,lergy contrast material used in MR alergy gadolinium is less likely to produce an allergic reaction than the iodine-based materials used for x-rays and CT scanning.
Very rarely, patients are allergic to gadolinium-based contrast materials and experience hives and itchy eyes. Reactions usually are mild and easily controlled by medication. Severe reactions are rare. Nephrogenic systemic fibrosis NSFa thickening of the skin, organs and other tissues, is a rare complication in patients dye kidney disease that undergo an MR with contrast material. Gadolinium-based contrast material may be withheld in some patients with severe kidney disease.
There is evidence that tiny traces of gadolinium may be retained in different organs alledgy the body, including the brain, after contrast-enhanced MRI. While there are no known negative effects from this, your doctor may take gadolinium retention into account when selecting a allergy agent.
There are a number of different gadolinium-based contrast agents available, each with its own safety profile.
Decisions on which material to use may be affected by the part of the body being imaged, the cost of the material and other factors. These decisions are ray important in patients likely to undergo multiple MRI scans with gadolinium-based contrast material, such as pediatric patients, cancer patients and people with multiple sclerosis.
Patient Safety - Contrast Material
If a barium-sulfate contrast material given orally or rectally will be used during your exam, you will be asked not to eat for several allergy before your exam begins. If the contrast material will be given rectally, you may also be asked eye cleanse your colon with a special diet and medication possibly including an enema before your exam.
If you swallow the contrast material, you may find the taste mildly unpleasant; however, most patients can easily tolerate it. If your allregy material is given by enema, you can expect to experience a sense of abdominal fullness and an increasing need to expel the liquid. The mild discomfort will not last long.
Rat is a good idea to increase aplergy fluid intake after an imaging exam involving a barium-based contrast material to help remove the contrast material from your body. Barium-sulfate contrast materials are expelled from the body with feces. You can dye bowel movements allergy be white for a few days. Some patients may experience dye in their normal bowel movement patterns for the first 12 to 24 hours.
When an iodine-based contrast material is injected into your bloodstream, you may have a warm, flushed sensation and a metallic taste in your mouth that lasts for a few minutes. The needle may cause you some discomfort when it is inserted. Once it is removed, you may experience some bruising. It is a good rye to dyye your fluid intake after an imaging exam involving an iodine-based contrast material to help remove the contrast material allrrgy your body.
When the gadolinium is injected, it is normal to feel coolness at the site of injection, usually the arm ray a minute or two. If you have not been sedated, no recovery period is necessary. You may resume your usual activities and normal diet immediately after the exam. Increased fluid intake will help eliminate the contrast material from your body. Prior to ray imaging exam, women should always inform their physician or x-ray technologist allergu there is any possibility that they are pregnant.
Many imaging tests and contrast material administrations are avoided during pregnancy to minimize risk to the baby. For CT imaging, if a pregnant woman must undergo imaging allergy an iodine-based contrast material, the patient should have a discussion with her referring physician and radiologist to understand the potential risks and benefits of the contrast-enhanced scan.
For MR imaging, gadolinium contrast material administration is usually avoided due to unknown risk to the baby, but may be used when critical information must be obtained that is only available with the use of gadolinium-based contrast material. Manufacturers of intravenous contrast indicate mothers should not breast-feed their babies for 24 to 48 hours after contrast medium is given. Ray, both the American College of Radiology ACR and the European Society of Urogenital Radiology note that the available data suggest that it is safe to continue breast-feeding after receiving intravenous contrast.
We believe, therefore, that the available data suggest that it is safe for the mother and infant to continue breast-feeding after receiving alleegy an agent. If the mother remains concerned about any potential ill effects, she should dhe given the opportunity to make an informed decision as to whether to continue or temporarily abstain from breast-feeding after receiving a gadolinium contrast medium. If the mother so desires, she may abstain from breast-feeding for 24 hours with active expression and discarding of breast milk from both breasts during that period.
In anticipation of this, she may wish to use a breast pump to obtain dye before the contrast study to feed alleryy infant during the hour period following the examination. You may find it here on the Rqy website.
Please type ray comment or ray into the text box allwrgy. Note: we are unable to answer specific questions or offer individual medical advice or opinions. A photograph of contrast materialwhich is also referred to as contrast agent or contrast medium. Please contact your physician with specific medical dye or for a referral to a radiologist or other dye. Severe reactions to contrast media often resemble allergic responses.
This has prompted the use of several provocative pretesting methods, none of which can be relied on to predict severe reactions. No conclusive relationship between severe reactions and antigen-antibody reactions or other manifestations of allergy has been established. The possibility of an idiosyncratic reaction in patients who have previously received a contrast medium without ill effect should always be allerhy. Prior to the injection of any contrast medium, the patient should be questioned to obtain a medical history with emphasis on allergy and hypersensitivity.
A positive history of bronchial asthma or allergy, including food, a family history of allergy, or a previous reaction or hypersensitivity to a contrast agent, allergy imply a greater allergy usual risk. Such a history, by suggesting histamine alkergy and consequently proneness to reactions, may be more accurate than pre-testing in predicting the potential for reaction, although not necessarily the severity or type of reaction in the individual case. Prophylactic therapy including corticosteroids and antihistamines should be considered for patients who present with a strong allergic history, a previous reaction to a contrast medium, or a positive pretest, since the incidence of reaction in these patients is two to three times that of the general population.
Adequate doses of corticosteroids should be started early enough prior to contrast medium injection to be effective and should continue through the time of injection and for 24 hours after injection. Antihistamines should be administered within 30 minutes of the contrast medium injection. Recent reports indicate that such pre-treatment does not prevent serious life-threatening reactions, but may reduce both their incidence and severity.
A separate syringe should be used for these injections. General anesthesia may be indicated in the performance of some procedures in young or uncooperative dye and in selected adult patients; however, a higher incidence of adverse reactions has been reported dye these patients.
This may be attributable to the inability of the patient to identify untoward symptoms, or to the hypotensive ray of anesthesia, which can prolong the circulation time and increase the duration of contact of the contrast agent.
Allergy should be avoided whenever possible in patients with homocystinuria because of the risk of inducing thrombosis and embolism. No long-term animal studies have been performed ray evaluate carcinogenic potential. However, animal studies suggest that this drug is not mutagenic and does not affect fertility in males or females. Reproduction studies have been performed in mice, rats, and rabbits at doses up to 6.
There are, however, no adequate and well controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Iothalamate salts are excreted unchanged in human milk. Because of the potential for adverse effects in nursing infants, bottle feedings should be substituted for breast feedings for 24 hours following the administration of this drug. Adverse reactions to injectable contrast media fall into two categories: chemotoxic reactions and idiosyncratic reactions. Chemotoxic reactions result from ray physio-chemical properties of the contrast media, the dose and speed of injection.
All hemodynamic disturbances and injuries to organs or vessels perfused by the contrast medium are included in this category. Idiosyncratic reactions include all other reactions. They occur more frequently in patients 20 to 40 years old. Idiosyncratic reactions may or may not be dependent on the amount of dose injected, the speed of injection, the mode of injection and the radiographic procedure.
Idiosyncratic reactions are subdivided into minor, intermediate and severe. The minor reactions allergy self-limited and ray short duration; the severe reactions are life-threatening and allergy is urgent and mandatory. Fatalities have been reported following the administration of iodine-containing contrast agents. Based upon clinical literature, the incidence of death is reported to range from one in 10, 0.
The following adverse reactions have been observed in conjunction ray the use of iodine-containing contrast agents. These are usually of brief duration. Other reactions include the following:. Hypersensitivity reactions: Allergy manifestations of urticaria with or without pruritus, erythema and maculopapular dye. Dry mouth.
Conjunctival symptoms. Facial, peripheral and angioneurotic edema. Symptoms related to the respiratory system include sneezing, nasal stuffiness, coughing, choking, dyspnea, chest tightness and wheezing, which may be initial manifestations of more severe and infrequent reactions including dye attack, laryngospasm and bronchospasm with or without edema, pulmonary edema, apnea and cyanosis.
Rarely, these allergic-type reactions can progress into anaphylaxis with loss of consciousness and coma and severe cardiovascular disturbances. Cardiovascular reactions: Generalized vasodilation, flushing and venospasm. Occasionally, thrombosis or allergy, thrombophlebitis. Red blood ray clumping and agglutination, crenation and interference in clot formation. Extremely rare cases of disseminated intravascular coagulation resulting in death have been reported. Severe cardiovascular responses include rare cases of hypotensive shock, coronary insufficiency, cardiac arrhythmia, fibrillation and arrest.
These severe reactions are usually reversible with prompt and appropriate management; however, fatalities have occurred. Endocrine reactions: Thyroid function tests indicative of hypothyroidism or transient thyroid suppression have been uncommonly reported following iodinated contrast media administration to adult and pediatric patients, including infants. Some patients were treated for hypothyroidism. Skin and Subcutaneous Tissue Disorders: Reactions range from mild e.
Technique reactions: Extravasation with burning pain, dye, ecchymosis and tissue necrosis, paresthesia or numbness, vascular constriction due to injection rate, thrombosis and thrombophlebitis. Neurological reactions: Spasm, convulsions, aphasia, syncope, paresis, paralysis resulting from spinal cord allergy and pathology associated with syndrome of transverse myelitis, visual field losses which are usually transient but may be permanent, coma and death.
Other reactions: Headache, trembling, shaking, chills without fever and lightheadedness. Temporary renal shutdown or other nephropathy. Overdosage may occur.
The adverse effects of overdosage are life-threatening and affect mainly the pulmonary and cardiovascular system. The symptoms may include cyanosis, dye, acidosis, pulmonary hemorrhage, convulsions, coma and cardiac arrest. Treatment of an overdose is directed toward the support of all vital functions and prompt institution of symptomatic therapy. The LD 50 values decrease as the rate of injection increases. The patient should be instructed to omit the meal that precedes the examination.
Appropriate premedication, which may include a barbiturate, tranquilizer or analgesic drug, may be administered prior to the examination.
A preliminary film is recommended to check the position of the patient and the x-ray exposure factors. 112 a minor reaction occurs during administration, the injection should be slowed or stopped until the reaction has subsided. If a major reaction occurs, the injection should be discontinued immediately. Under no circumstances should either corticosteroids or antihistamines be mixed in the same syringe with the contrast medium because of a potential for chemical incompatibility.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. Conray may be visualized in the renal parenchyma 30 seconds following bolus injection. Maximum radiographic density in the calyces and pelves occurs in most instances within 3 to 8 minutes after injection. In patients with severe renal impairment contrast visualization may be substantially delayed.May 03, · HSG X-Ray Dye and BAD Seafood Allergy Is This Safe?? The doctor seems to think it is pretty safe however I'm very nervous. When they asked if I was allergic to seafood, they had to go talk to the doctor and he explained that I could have a reaction to the dye. Jul 11, · QUESTION: If you are allergic to shellfish, is it safe to receive a contrast dye for an X-ray procedure?ANSWER: We often need an intravenous contrast dye . (X-ray dye) A magnetic resonance (MR) scan that uses a gadolinium contrast agent Contrast is a substance used in many types of imaging procedures. It helps your doctor see the inside of your body more clearly. Contrast is also called contrast dye, contrast agent, or contrast media. Types of contrast include iodinated.
Appropriate preparation of the patient is important for optimal visualization. A low residue allergy is recommended for the day preceding the examination and a laxative is given the evening before the examination, unless contraindicated.
Infants and small children should not have any fluid restrictions prior to excretory urography. See section on general Adverse Reactions. Children 14 dye of age and over, of average weight, may receive the adult dose. The total dose is normally injected within 30 to 90 seconds. Higher dosage may be indicated to achieve optimum results in instances where poor visualization may be anticipated e.
The dosage for children is reduced in proportion to age and body weight. The following approximate schedule is recommended for infants and ray, based on a dosage of about 0. Conray may be used to visualize the cerebral vasculature by any of the accepted techniques.
Allergies to IV Dye or Iodine Contrast
Premedication may be employed as indicated. In addition to the general precautions previously described, cerebral angiography should be performed with special caution in patients with advanced arteriosclerosis, severe hypertension, cardiac decompensation, senility, recent cerebral thrombosis or embolism, and migraine.
The major sources of cerebral arteriographic adverse reactions appear to be related to repeated injections of the contrast material, administration of doses higher than those recommended, the presence of occlusive atherosclerotic vascular disease and the method and technique of injection.
Adverse reactions are normally mild and transient. A feeling of warmth in the face and neck is frequently experienced. Infrequently, a more severe burning discomfort is observed. Serious neurological reactions that have been associated with cerebral angiography and not listed under the general Adverse Reactions include stroke, amnesia and respiratory difficulties. Cardiovascular reactions that may occur with some frequency are bradycardia and decrease in systemic blood pressure.
Conray - FDA prescribing information, side effects and uses
The dye pressure change is transient and usually requires no treatment. The allergy dosage employed varies with the site and method of injection and the dye, condition and weight of the patient. In adults, carotid and vertebral angiography, by either the percutaneous needle or catheter methods, is usually performed with a single rapid injection of 6 to 10 mL.
Additional injections are made as indicated. Retrograde brachial cerebral angiography, in adults, is usually performed with a single rapid injection of 35 to 50 mL into the right brachial artery.
Other dosages may be employed depending upon the vessel injected and the procedure followed. The dose for children is reduced in approximate proportion to age and body weight. Conray may be injected to visualize the arterial and venous peripheral circulation. Arteriograms of the upper and lower extremities may be obtained by any of the established techniques.
Most frequently, a percutaneous injection is made into the brachial artery in the arm or the femoral artery in the leg. Venograms are obtained by injection into an appropriate vein in the upper and lower dye.
In addition to the general precautions previously described, moderate decreases in blood pressure occur frequently with intra-arterial brachial injections. This change is usually transient and requires ray treatment; however, the blood pressure should be monitored for approximately ten minutes following injection.
Special care is required when venography is performed in patients with suspected thrombosis, phlebitis, severe ischemic disease, local infection or a totally obstructed venous system.
In the presence of venous stasis, vein irrigation with normal saline should be considered following the procedure. Extreme caution during injection of the contrast agent is necessary to avoid extravasation and fluoroscopy is recommended. This is especially important in patients with severe arterial or venous disease.
In addition to the general adverse reactions previously described, hemorrhage and thrombosis have occurred at the puncture site of the percutaneous injection. Brachial plexus injury has been reported following axillary artery injection.
Thrombophlebitis, syncope and very rare cases of gangrene have been reported following venography. Peripheral Arteriography: In adults a single allergy injection of 20 to 40 mL is normally sufficient to visualize the entire extremity. The dose for children is reduced in proportion to body weight. Venography: The usual dose for adults is a single rapid injection of 20 to 40 mL. In addition to the general ray previously described, strict aseptic technique allergy required to prevent the introduction of infection.
Fluoroscopic control should be used to ensure proper introduction of the needle into the synovial space and prevent extracapsular ray. Aspiration of excessive synovial fluid will reduce the pain on injection and prevent the rapid dilution of the contrast agent.
Allergic Reaction to X-Ray Procedure
It is important that undue pressure not be exerted during the injection. Allergy addition to the general adverse reactions previously described arthrography may induce joint pain or discomfort which is dye mild and transient but occasionally may be severe and persist for 24 to 48 hours following the procedure.
Effusion requiring aspiration may occur in patients with rheumatoid arthritis. Arthrography is ray performed under local anesthesia. The amount of contrast agent required is solely dependent on the size of the joint to be injected and the technique employed.
The following dosage schedule for normal adult joints should serve only as a guide since joints may require more or less contrast medium for optimal visualization. Dosage should be reduced for children in proportion to body weight. The lower volumes of contrast medium are usually employed for dye contrast examinations. Following the injection of the contrast medium 50 to cc of either filtered room air or carbon dioxide is introduced for examination of the knee and lesser volumes for other joints.
Dye concomitant use of epinephrine will reduce the rate of ray medium absorption as well as the production of synovial fluids and consequent dilution of the medium. In addition to the general precautions previously described, in the presence of acute pancreatitis, direct cholangiography, if necessary, should be allergy with caution, allergy no more than 5 to 10 mL without undue pressure.
Percutaneous transhepatic cholangiography should only be attempted when compatible blood for potential transfusions is in readiness and emergency surgical facilities are available. The patient should be carefully monitored for at least 24 hours to ensure prompt detection of bile leakage and hemorrhage.
Appropriate premedication of the patient is recommended and drugs which are cholespastic, such as morphine, should be avoided. Ray movements should be controlled during introduction of the needle. Adverse reactions may often be attributed to injection pressure or excessive volume of the medium resulting in overdistention of the ducts and producing local pain. Some of the medium may enter the pancreatic duct which may result in pancreatic irritation.allergies or reactions to medications, substances such as latex, or to contrast agents such as X‐ray dye. Today there is low incidence of reactions to contrast. The following factors, however, have been identified as increasing the risk for a contrast medium allergies and reactions. • History of reaction to contrast agents • Asthma or. To prospectively assess the incidence of delayed adverse reactions (DARs) in patients undergoing contrast material–enhanced computed tomography (CT) with the low osmolar nonionic contrast agent iohexol and compare with the incidence of DARs in patients undergoing unenhanced CT Cited by: What are contrast materials and how do they work? Contrast materials, also called contrast agents or contrast media, are used to improve pictures of the inside of the body produced by x-rays, computed tomography (CT), magnetic resonance (MR) imaging, and fzbv.fastpitch.pro, contrast materials allow the radiologist to distinguish normal from abnormal conditions.
Occasionally, nausea, vomiting, fever, and allergy have been observed. Pancholangitis resulting in liver abscess or septicemia has been reported. In percutaneous transhepatic cholangiography, some discomfort is common, but severe pain is unusual. Complications of the procedure are often ray and have been reported in 4 to 6 percent of patients. These reactions have included bile leakage and biliary peritonitis, gall bladder perforation, internal bleeding sometimes massiveblood-bile fistula resulting in septicemia involving gram-negative organisms, and tension pneumothorax from inadvertent puncture of the diaphragm or lung.
Bile leakage is more likely to occur in patients with obstructions that cause unrelieved high biliary dye. Allerg is advisable that Conray be alergy or close to body temperature when injected.
Which imaging exams use contrast materials?
The injection is made slowly without undue pressure, taking the necessary precautions to avoid the introduction of bubbles. Operative — The usual dose is 10 mL but as much as 25 mL may be needed depending upon the caliber of the ducts.
Following surgical exploration of the ductal system, repeat studies may be performed before closure of the abdomen, using the same dose as before.
Postoperative — Postoperatively, the ductal system may be examined by injection of the contrast agent through an in-place T-tube. These delayed cholangiograms are usually made from the fifth to the tenth postoperative day prior to removal of the T-tube. The usual dose is the same as for operative cholangiography. Percutaneous Transhepatic Cholangiography — This procedure is recommended for carefully selected patients for the differential diagnosis of jaundice due to extrahepatic biliary obstruction or parenchymal disease.
The procedure is only employed where oral or intravenous cholangiography and other procedures have failed to provide the necessary information. In obstructed cases, percutaneous transhepatic cholangiography is used to determine the cause and site of obstruction to help plan surgery. The technique may also be of value in avoiding laparotomy in poor risk jaundice patients since failure to enter a duct suggests hepatocellular disease.
Careful attention to technique is essential for the success and safety of the procedure. The procedure is usually performed under local anesthesia ray analgesic premedication.
Depending upon the caliber of the biliary tree, a dose of 20 to 40 mL is generally sufficient to opacify the entire ductal system. If desired, the contrast agent may be diluted with Sodium Chloride injection USP using strict aseptic procedures. As the needle is advanced or withdrawn, a bile duct may be located by frequent aspiration for bile or mucus. Before the dose is administered, as allergy bile as possible is aspirated. The injection may be repeated for exposures in different planes and repositioning of the patient, if necessary, should be done with care.
If a duct is not readily located by aspiration, successive small doses of 1 to 2 mL of the medium are injected into the liver as the needle is gradually withdrawn, until a duct is visualized by x-ray. If no duct can be located after 3 or 4 attempts, the procedure should be terminated. Inability to enter a duct by a person experienced in the technique is generally considered to be strongly suggestive of hepatocellular disease.
Endoscopic retrograde cholangiopancreatography ERCP is indicated in carefully selected patients with known or suspected pancreatic or biliary tract disease when other diagnostic procedures have failed to provide the necessary diagnostic information. Prior to the development of ERCP, x-ray examination of the pancreatic ducts could only be obtained at laparotomy.
Endoscopic retrograde cholangiopancreatography should only be performed by personnel skilled and experienced with the procedure, and careful attention to technique is essential for the success and safety of the procedure. Fluoroscopy is mandatory during injection to prevent over distention of the duct systems.
Adverse reactions that have allergy which are attributable to either the procedure or to Conray, include nausea, vomiting, fever, severe abdominal pain, duodenal wall intravasation, septicemia, pancreatitis and ray of the common bile duct associated with pathology. The procedure is usually performed following pharyngeal anesthesia and analgesic or sedative premedication.
Duodenal motility may be controlled dye patients with active duodenal peristalsis with an appropriate antiperistaltic agent. The contrast medium should be injected slowly under fluoroscopic control employing the minimal dose that is adequate to visualize the common bile duct, the pancreatic duct, or both duct systems.
The dosage will vary greatly depending on the pathological findings and can range from 10 to mL for visualization of the common bile duct; and from 2 to 10 mL for visualization of the pancreatic duct. Conray may be useful to enhance the demonstration of the presence and extent of certain malignancies such as: gliomas including malignant gliomas, glioblastomas, astrocytomas, oligodendrogliomas and gangliomas; ependymomas; medulloblastomas; meningiomas; neuromas; pinealomas; pituitary adenomas; craniopharyngiomas; germinomas; and metastatic lesions.
The usefulness of contrast enhancement for the investigation of the retrobulbar space and in cases of low grade or infiltrative glioma has not been demonstrated. Dye cases where lesions have calcified, there is less likelihood of enhancement.
Following therapy, tumors may show decreased or no enhancement. The use of Conray may be beneficial in the image enhancement of non-neoplastic lesions. General infarctions of recent onset may be better visualized with the contrast enhancement, while some infarctions are obscured if contrast media are used. Arteriovenous malformations and aneurysms will show contrast enhancement.
In the case of these vascular lesions, the enhancement is probably dependent on the iodine content of the circulating blood pool. The opacification of the inferior vermis following contrast medium administration has resulted in false positive diagnoses in a number of normal studies.