Gadolinium-based Contrast Agent Accumulates in the Brain Even in Subjects without Severe Renal Dysfunction: Evaluation of Autopsy Brain Specimens with Inductively Coupled Plasma Mass Spectroscopy. The prevention of immediate generalized reactions to radiocontrast media in high-risk patients. J Magn Reson Imaging (full text) - doi:10.1002/jmri.22666 - Pubmed citation Safety of gadolinium-based contrast material in sickle cell disease. NOTE: This article was originally transferred from and was last updated in June 23, 2015. Please review and edit if more information becomes available. However, the phenomenon is currently under investigation by the FDA 7. The clinical effect of this deposition, if any, is currently unknown. Gadolinium is deposited in the brain in patients with normal renal function 3. Gadolinium retention is not considered to be related to radiation therapy in patients receiving multiple studies for head and neck cancer 6. The effect is thought to be more common with linear gadolinium chelates rather than with cyclic chelates 4,5. This is thought to be related to retained gadolinium contrast at these sites. There are reports that repeated administrations of IV gadolinium contrast leads to T1 shortening in the dentate nuclei, and possibly the globus pallidus 3. No clinical reports of this potential problem have been found 1. Most of these symptoms occurred 25-85 minutes after the injection.ĭeoxygenated sickle erythrocytes align perpendicular to a magnetic field in vitro studies raising the possibility of occlusive complications in patients with sickle cell anemia. A study of 1,068 patients reported hypotension in 0.3% of the subjects and other symptoms such as syncope probably associated with hypotension in 0.8%. Transient and mild drop blood pressure is reported in both animals and humans. The platelet aggregation inhibition is less than that seen with iodinated ionic contrast material and no bleeding problems are reported clinically. A 10-11% increase in the activated partial thromboplastin time and thrombin time occurs in vitro with inhibition of platelet aggregation. The mechanism of these elevations is uncertain but may be related to mild hemolysis. These elevations peaked at 4 to 6 hours post-injection and returned to baseline values in 24 to 48 hours. Gadolinium-containing contrast agents usually have no effect on blood chemistries and hematologic studies except transient elevation of serum iron and bilirubin levels. Prophylactic pharmacotherapy with antihistamines and corticosteroids, such as Greenberger's protocol, is suggested for high-risk patients prior to contrast injections 2. It is suggested that the threshold for injecting gadolinium be raised, in those patients, based on an individual risk/benefit ratio. Potential risk factors may include a history of asthma and significant reaction to previously administered iodinated contrast material. The frequency of these reactions is about 1 in 100,000 doses. Reports of several episodes of severe anaphylactoid reactions after IV injection of Gd-DTPA are published. The elimination half-life for the Gd-containing contrast agents range from 1.25-1.6 hours. The safety factor or ratio (ratio of the LD50 to the imaging dose) may be used to assess the relative acute toxicity of contrast agents. Recent adverse rates for Gd-DTPA are lower than this and comparable to those of gadodiamide and gadoteridol (1.4%-3% for headache, nausea, and dizziness <1% for the others). The most commonly reported reactions associated with the injection of Gd-DTPA are See also: nephrogenic systemic fibrosis Adverse reactions Intravenous gadolinium contrast agent safety With chelation of these ions, acute toxicity is reduced and elimination rate is increased, thereby reducing the chance of long-term toxicity. Paramagnetic metal ions suitable as MRI contrast agents are all potentially toxic when injected IV at or near doses needed for clinical imaging. Though considered safer than the frequently used iodinated contrast agents used in x-ray and CT studies, there are safety issues with MRI contrast agents as well.
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