Magnetic resonance imaging (MRI) is clearly the best way to evaluate people with multiple sclerosis (MS). CT scans do not show MS activity well and they do use ionizing radiation that may cause DNA damage or cancer.
Instead, MRI uses a magnetic field and radio waves to produce images of your brain and/or spinal cord. In some cases, however, a contrast dye called gadolinium is injected to obtain additional information (This is typically called a contrast-enhanced MRI.).
Safety concerns with MRI contrast and people with kidney disease began in 2006, when the use of gadolinium based contrast agents were linked to the development of nephrogenic systemic fibrosis, a debilitating and sometimes fatal condition affecting predominately the skin and kidneys. The incidence of nephrogenic systemic fibrosis was decreased dramatically, however, with the development of clinical protocols that restrict the use of gadolinium contrast in patients with impaired kidney function. MRI contrast should be avoided in patients with significant kidney dysfunction or recent kidney injury (not simple urinary tract infections or bladder control issues).
There are risks involved when anything, including MRI contrast, is injected into the body. It should also be avoided in patients who are allergic to it. When use in allergic people is necessary, pre-medications will lower the risk of severe allergic reactions. Gadolinium contrast should be avoided when patients are pregnant or breast-feeding.
An emerging concern with MRI contrast is that the body may not fully eliminate the gadolinium and that some of it may remain in the body. Recent studies have revealed that the gadolinium contrast may remain in the body, particularly the brain or bones. Until recently, the medical community was unaware that gadolinium contrast was not completely excreted by people with healthy kidneys and, at least in some patients, gadolinium remained in the body. No study has shown this gadolinium to be harmful; however, as we did not know this process occurred, adequate studies of long-term safety have not been completed. We believe that given the likelihood of numerous MRI scans for people with MS over a lifetime that this is an important issue. We are aware that the National MS Society is formulating an information and action plan.
The FDA on July 27, 2015, issued a drug safety communication about gadolinium based contrast. We want our patients to know that we are aware of the issue. Patients should be advised that, as of yet, there is no proven clinical sequelae of gadolinium contrast deposition into the brain or bone tissue. We support additional research into better understanding this process and will likely modify how we do some of our MRI scans. MRI contrast does provide some unique information and is unlikely to be eliminated from use unless other issues are discovered.
Until more information arises, we may use gadolinium contrast less frequently with MRI scans. From currently available data, it appears that some of the MRI contrast agents may have more risk of gadolinium release into the body than others. The agents OptiMARK, Omniscan, and Magnevist appeared to have a higher risk for gadolinium release into tissues. Gadavist may have less release than the above; however, we prefer Dotarem, Prohance, or Multihance as they appear to have less release and will hopefully cause less accumulation of gadolinium in the brain. People with MS may ask the MRI facility they use what contrast agent they are being given. We believe, with good MRI processing protocols such as the 2015 CMSC MRI protocol, many of our follow-up scans will not require contrast agents. These protocols include thinner sections and no gaps between the sections.
We like our patients to be informed. This information is evolving. Please feel free to ask our team members about any additional questions that you have.
Please call us with concerns so we may alter your MRI order to account for Gadolinium contrast.