When is an MRI contrast agent necessary?
An MRI without contrast medium is largely risk-free, but is not sufficient for all questions. Whenever questionable tissue is shown in similar shades of gray, the use of a contrast agent makes sense. This is the case, for example, when examining suspicious foci in the spleen, pancreas or liver or when clarifying tumors and metastases. Areas with poor blood supply can also be found using contrast agents, for example scarring or blocked blood vessels after strokes.
Contrast agents used in MRI
Substances containing gadolinium, iron oxides and manganese compounds are often used for an MRI with contrast medium. While gadolinium may only be administered via a vein, the patient can also drink the other two substances. This is particularly useful for examinations of the gastrointestinal tract.
MRI contrast agents: side effects
In healthy patients, MRI contrast agents generally only cause mild side effects such as
- Feeling of warmth, cold or tingling
- headache
- General malaise
- skin irritation
In some cases, MRI contrast media can also cause allergic reactions.
In rare cases, the administration of contrast media containing gadolinium can lead to so-called nephrogenic systemic fibrosis (NSF) in the case of existing renal insufficiency. This connective tissue disease is characterized by a proliferation of connective tissue in the skin, joints or internal organs. Gadolinium may also be deposited in certain areas of the brain. This can lead to secondary symptoms such as pain or paresthesia.
A reassessment of the safety profile is the subject of controversial debate among experts. However, the contrast agents gadobutrol, gadoteric acid and gadoteridol are currently still being used, albeit with the recommendation to use them in the lowest possible dosage. In the interests of patient safety, doctors decide on the use of gadolinium-containing contrast media on a case-by-case basis after weighing up the risks and benefits.
