Medical imaging forms a vital part of modern healthcare. But getting consistently clear, accurate images is not always a straightforward process. For orally administered contrast agents, patient compliance is key. In addition to being optimized for image quality, procedures should also be optimized for patient experience.
Contrast media are drug products that can be administered orally or by injection in order to enhance structures in the body and allow medical professionals to evaluate function. A wider selection of different contrast media would provide options for healthcare providers to manage cost by individualizing care based on each patient’s history, condition, and in the case of agents that need to be swallowed, personal taste.
At this year’s annual Radiological Society of North America (RSNA) meeting, the power of choice is being showcased, that could affect patients’ experience of medical imaging for the better. These choices, which are only available from GE Healthcare, include iodinated contrast, eco-friendly packaging, and contrast management.
Omnipaque™ (iohexol) Injection is a contrast medium with 39 indications approved for intravenous, intra-arterial, and intrathecal administration and the only low-osmolar contrast medium that is FDA-approved for oral and body cavity use. The taste of iodinated contrast isn’t a patient favorite, but in taste tests, most patients, including children, drank the entire recommended dose of Omnipaque and indicated that they would do so again[i]. Oral use of Omnipaque is associated with mild transient diarrhea, especially following high concentrations and volumes that may result in hypovolemia. Plasma fluid loss may be sufficient to cause a shock-like state that, if untreated, could be dangerous, especially in the elderly, patients of any age with cachexia infants and small children.
A second contrast medium on display is Visipaque™ (iodixanol). It is an injected contrast medium that may be suitable for the special needs of certain patients and is used in more than 50% of various arteriography and venography procedures (imaging of arteries and veins) taking place in cardiac catherization labs in the United States.[ii]
[i] Smevik B, Westvik J. Iohexol for contrast enhancement of bowel in pediatric abdominal CT. Acta Radiol. 1990;31:601-604. 2. Lönnemark M, Magnusson A. Oral contrast media in CT of the abdomen: iohexol of different concentrations as a gastrointestinal contrast medium. Acta Radiol. 1995;36:396-398.
[ii] Data on file. GE Healthcare; 2013.
Important Risk and Safety Information About Omnipaque™ (iohexol) Injection
INDICATIONS: Oral/Body Cavity Use — Adults: Omnipaque 350 is indicated for arthrography and oral pass-through examination of the gastrointestinal (GI) tract.
Omnipaque 300 is indicated for arthrography and hysterosalpingography. Omnipaque 240 is indicated for arthrography, endoscopic retrograde pancreatography and cholangiopancreatography, herniography, and hysterosalpingography. Children: Omnipaque 300 is indicated for examination of the gastrointestinal (GI) tract. Omnipaque 240 is indicated for examination of the GI tract. Omnipaque 180 is indicated for examination of the GI tract. Omnipaque diluted to concentrations from 50 mgI/mL to 100 mgI/mL is indicated for voiding cystourethrography. Oral/IV Use: Oral Omnipaque diluted to concentrations from 9 mgI/mL to 21 mgI/mL (pediatric) or 6 mgI/mL to 9 mgI/mL (adult), administered orally in conjunction with Omnipaque 240 (pediatric) or 300 (pediatric and adult) administered intravenously, is indicated for use in contrast-enhanced computed tomography of the abdomen.
CONTRAINDICATIONS: Omnipaque should not be administered to patients with a known hypersensitivity to iohexol.
WARNINGS — Oral/Intravascular Use: Serious, rarely fatal, thromboembolic events causing myocardial infarction and stroke have been reported during angiographic procedures with both ionic and nonionic contrast media. Omnipaque should be used with extreme care in patients with severe functional disturbances of the liver and kidneys, severe thyrotoxicosis, or myelomatosis. Diabetic patients with a serum creatinine level above 3 mg/dL should not be examined unless the possible benefits of the examination clearly outweigh the additional risk. Omnipaque is not recommended for use in patients with anuria. Contrast media are potentially hazardous in patients with multiple myeloma or other paraproteinemia. Ionic contrast media, when injected intravenously or intra-arterially, may promote sickling in individuals who are homozygous for sickle cell disease. Administration of contrast to patients known or suspected of having pheochromocytoma should be performed with extreme caution, and the dose injected should be kept to an absolute minimum. The patient’s blood pressure should be assessed throughout the procedure, and measures for the treatment of hypertensive crisis should be readily available. Incidences of thyroid storm have been reported following the use of iodinated, ionic contrast media in patients with hyperthyroidism or with an autonomously functioning thyroid nodule. Urography should be performed with caution in patients with severely impaired renal function and in patients with combined renal and hepatic disease.
PRECAUTIONS — General: Patients should be well hydrated prior to and following administration of any contrast medium. The possibility of a reaction, including serious,
life- threatening, fatal, anaphylactoid, cardiovascular (CV), or central nervous system reactions, should always be considered. The possibility of an idiosyncratic reaction in susceptible patients should always be considered. The susceptible population includes, but is not limited to, patients with a history of a previous reaction to contrast media, patients with a known sensitivity to iodine, and patients with a known clinical hypersensitivity such as bronchial asthma, hay fever, and food allergies. After parenteral administration of a contrast agent, competent personnel and emergency facilities should be available for at least 30 to 60 minutes, since severe, delayed reactions have occurred. Renal Impairment: Use in patients with hepatorenal insufficiency only if the possibility of benefit clearly outweighs the additional risk. Diabetic Patients: Acute renal failure has been reported in diabetic patients with diabetic nephropathy and in susceptible nondiabetic patients (often elderly with preexisting renal disease) following excretory urography. Congestive Heart Failure (CHF): The potential transitory increase in the circulatory osmotic load in patients with CHF requires caution during injection. These patients should be observed for several hours following the procedure to detect delayed hemodynamic disturbances. General anesthesia may be indicated in the performance of some procedures in selected adult patients; however, a higher incidence of adverse reactions has been reported in these patients. Angiography should be avoided whenever possible in patients with homocystinuria, because of the risk of inducing thrombosis and embolism. Selective coronary arteriography should be performed only in those patients in whom the expected benefits outweigh the potential risk. Repeat Procedures: If in the clinical judgment of the physician, sequential or repeat examinations are required, a suitable interval of time between administrations should be observed to allow for normal clearance of the drug from the body. Nursing Mothers: It is not known to what extent iohexol is excreted in human milk. However, many injectable contrast agents are excreted unchanged in human milk. Although it has not been established that serious adverse reactions occur in nursing infants, caution should be exercised when intravascular contrast media are administered to nursing women. Bottle feedings may be substituted for breastfeedings for 24 hours following administration of Omnipaque. Pediatric Use: Pediatric patients at higher risk of experiencing adverse events during contrast medium administration may include those having asthma, sensitivity to medication and/or allergens, CHF, a serum creatinine greater than 1.5 mg/dL, or those younger than 12 months of age.
ADVERSE REACTIONS — Oral Use: Is associated with mild, transient diarrhea, especially following high concentrations and volumes, which may result in hypovolemia. Plasma fluid loss may be sufficient to cause a shock-like state that, if untreated, could be dangerous, especially in the elderly, cachectic patients of any age, and infants and small children. General Reactions to Contrast Media: Serious, life-threatening, and fatal reactions, mostly of CV origin, have been associated with the administration of all iodine-containing contrast media. Aseptic meningitis syndrome has been reported rarely. Profound mental disturbances have been reported rarely, usually consisting of various forms and degrees of aphasia, mental confusion, or disorientation. The onset is usually at eight to 10 hours and lasts for about 24 hours, without aftereffects. Rarely, persistent though transitory weakness in the leg or ocular muscles has been reported. Peripheral neuropathies have been rare and transitory. In general, the reactions, which are known to occur upon parenteral administration of iodinated contrast agents, are possible with any nonionic agent. The reported incidence of adverse reactions to contrast media in patients with a history of allergy is twice that of the general population. Patients with a history of previous reactions to a contrast medium are three times more susceptible than other patients. Most adverse reactions to injectable contrast media appear within one to three minutes after the start of injection, but delayed reactions may occur. The injection of contrast media is frequently associated with the sensation of warmth and pain, especially in peripheral angiography.
Prior to Omnipaque administration, please read the Full Prescribing Information.
Important Risk and Safety Information About Visipaque™ (iodixanol) Injection
SEVERE ADVERSE EVENTS DUE TO INADVERTENT INTRATHECAL ADMINISTRATION: Serious adverse reactions have been reported due to the inadvertent intrathecal administration of iodinated contrast media (CM) that are not indicated for such use. These reactions include death, convulsions, cerebral hemorrhage, coma, paralysis, arachnoiditis, acute renal failure, cardiac arrest, seizures, rhabdomyolysis, hyperthermia, and brain edema. Assure that Visipaque product is not administered intrathecally.INDICATIONS — Intra-arterial (IA): Visipaque Injection (270 mgI/mL) is indicated for IA digital subtraction angiography. Visipaque Injection (320 mgI/mL) is indicated for angiocardiography (left ventriculography and selective coronary arteriography), peripheral arteriography, visceral arteriography, and cerebral arteriography. Intravenous (IV): Visipaque Injection (270 mgI/mL and 320 mgI/mL) is indicated for computed tomography (CT) of the head and body, and excretory urography. Visipaque Injection (270 mgI/mL) is also indicated for peripheral venography. CONTRAINDICATIONS: Visipaque Injection is not indicated for intrathecal use. In pediatric patients, prolonged fasting and administration of a laxative before a Visipaque Injection are contraindicated. WARNINGS: Serious, rarely fatal, thromboembolic events causing myocardial infarction and stroke have been reported during angiocardiographic procedures with CM. Serious or rare fatal reactions have been associated with the administration of iodine-containing CM. Use caution in patients with severely impaired renal function (either alone or combined with hepatic or cardiac disease), severe thyrotoxicosis, myelomatosis, or anuria, especially if administering large doses. Intravascular iodinated CM are potentially hazardous in patients with multiple myeloma or other paraproteinaceous diseases and in patients who are prone to disease-induced renal insufficiency and/or renal failure. Thyroid storm has been reported following intravascular use of iodinated CM in patients with hyperthyroidism or an autonomously functioning thyroid nodule. Use extreme caution administering CM to patients known to have, or are suspected of having, pheochromocytoma. CM may promote sickling in individuals homozygous for sickle cell disease. PRECAUTIONS — General: CMs are associated with risk and increased radiation exposure. Dehydration, Renal Insufficiency, Congestive Heart failure (CHF): Prestudy dehydration is dangerous and may contribute to acute renal failure in patients with advanced vascular disease, congestive heart disease, diabetic patients, and others such as those on medications that alter renal function and the elderly with age-related renal impairment. Patients should be adequately hydrated prior to and after intravascular iodinated CM. Dose adjustments in renal impairment have not been studied. Iodinated CM may cross the blood-brain barrier (BBB). In patients where the BBB is known or suspected of disruption, or in patients with normal BBB and associated renal impairment, caution must be exercised in the use of iodinated CM. Patients with CHF receiving concurrent diuretic therapy may have relative intravascular volume depletion, which may affect the renal response to the CM osmotic load. Renal Insufficiency: In patients with significantly impaired renal function, the total clearance of iodixanol is reduced and the plasma half-life is prolonged. In a study of 16 adult patients scheduled for renal transplant, the plasma half-life was 23 hours (normal = two hours). Dose adjustments in patients with renal impairment have not been studied. Visipaque does not bind to plasma or serum protein and can be dialyzed. Immunologic Reactions: Always consider the possibility of a reaction, including serious, life-threatening, fatal anaphylactoid or cardiovascular (CV) reactions. Anesthesia: A higher incidence of adverse reactions has been reported in patients receiving general anesthesia. Venography: Exercise extreme caution during CM injection to avoid extravasation, especially in patients with severe arterial or venous disease. CT: The use of CM may obscure some lesions seen on previous, unenhanced scans. Pediatric Use: Pediatric patients at high risk of adverse reactions during and after administration of CM include those with asthma, hypersensitivity to other medication and/or allergens, cyanotic and acyanotic heart disease, CHF, or a serum creatinine >1.5 mg/dL. Patients with immature renal function or dehydration may be at increased risk due to prolonged elimination of iodinated CM. The injection rates in small vascular beds and the relationship of the administered volume or concentration of iodinated CM in small neonates, infants, and small pediatric patients have not been established. In pediatric patients <1 year, the relative safety of the volumes injected, the optimal concentrations, and the potential need for dose adjustment because of prolonged elimination half-lives have not been systematically studied. In pediatric patients studied, adverse events were associated with decreasing age and IA procedures. Geriatric Use: While no overall differences in safety or effectiveness were observed in patients >65 years, greater sensitivity regarding some older individuals cannot be ruled out. As Visipaque is substantially excreted by the kidney, the risk of toxic reactions may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function. Nursing Mothers: It is not known whether Visipaque is excreted in human milk; however, many injectable CM are excreted unchanged in human milk. Consideration should be given to temporarily discontinuing nursing. ADVERSE REACTIONS: Serious, life-threatening, and fatal reactions, mostly of CV origin, have been associated with the administration of iodine-containing CM, including Visipaque Injection. Most deaths occur during injection or five to 10 minutes later. Rare reports of anaphylaxis have been documented during postmarketing surveillance. As with other CM, Visipaque is often associated with sensations of discomfort, warmth, or pain. The reported incidence of adverse reactions to CM in patients with a history of allergy is twice that of the general population. Patients with a history of a previous reaction to CM are three times more susceptible than other patients. DRUG INTERACTIONS: Renal toxicity has been reported in a few patients with liver dysfunction who were given an oral cholecystographic agent followed by intravascular CM. Other drugs should not be mixed with Visipaque. OVERDOSAGE: The adverse effects of CM overdose may be life-threatening, affecting mainly the pulmonary and CV systems.Prior to use, please read the Full Prescribing Information for Visipaque Injection.