CT or MRI With or W/O Contrast?

[Davis]

Has anyone else ever wondered why the medical community would, as regular practice if you look at the numbers, prescribe/schedule an MRI without contrast as routine but yet routinely also prescribe an MRI WITH contrast to follow? Is it just my paranoia or is this just another business/money thing? Was curious as to what anyone else thought.

[junosand]

good reasons for MRI with & without contrast

MRI is a great technology, it uses magnetic properties to produce its images; wiki has a full discussion if you really want to learn about how it works

the contrast agent gadolinium will cause tumors, ms plaques and other things to 'glow' or enhance and does provide further information if something is suspected on the non-contrast images or a comparison of the two can indicate whether an abnormality is old and inactive or more recent and active

so, no, you shouldn't be suspicious of physician's motivations; with a few exceptions, the doctors ordering the scans make no money from them; that was the case for me - i ordered them for my patients and then read them but they got the scans at the local hospital or imaging center who were the ones billing them; i made no money ordering or looking at them

[Davis]

I understand how the Magnetic Resonance Imaging works, but as far as the contrast agent, is Gadolinium the only thing used? Do different DR's use different contrast agents or is it a strict universal thing to use gadolinium? Please excuse my ignorance.

[twinsmom]

Our Experience

My daughter had both MRIs. They were looking for infection. Our problem was more logistics since we had to travel to a further away med center for the MRI with contrast. It also was much more of an ordeal. When they were ordered I didn't think to ask about the whys and wherfores. Just wasn't thinking that way. Mary

[junosand]

contrast agents

in the US, for all practical purposes, gadolinium is the only one but there are others for being developed or used in research scanning; here's the wiki entry:

"Contrast agents
Main article: MRI contrast agent

The most commonly used intravenous contrast agents are based on chelates of gadolinium. In general, these agents have proved safer than the iodinated contrast agents used in X-ray radiography or CT. Anaphylactoid reactions are rare, occurring in approx. 0.03–0.1%.[42] Of particular interest is the lower incidence of nephrotoxicity, compared with iodinated agents, when given at usual doses—this has made contrast-enhanced MRI scanning an option for patients with renal impairment, who would otherwise not be able to undergo contrast-enhanced CT.[43]

Although gadolinium agents have proved useful for patients with renal impairment, in patients with severe renal failure requiring dialysis there is a risk of a rare but serious illness, nephrogenic systemic fibrosis, that may be linked to the use of certain gadolinium-containing agents. The most frequently linked is gadodiamide, but other agents have been linked too.[44] Although a causal link has not been definitively established, current guidelines in the United States are that dialysis patients should only receive gadolinium agents where essential, and that dialysis should be performed as soon as possible after the scan to remove the agent from the body promptly.[45] In Europe, where more gadolinium-containing agents are available, a classification of agents according to potential risks has been released.[46][47] Recently a new contrast agent named gadoxetate, brand name Eovist (US) or Primovist (EU), was approved for diagnostic use: this has the theoretical benefit of a dual excretion path.[48]"