Other questions about MRI scans vs PET/CT

[Bluebird11]

I wrote a few weeks about about this question. One of the responses was:

justfor

15 days ago

The health hazard from a PET/CT comes from two components:

That of the radiotracer and the CT irradiation.

How to minimize each of them:

1) Higher sensitivity scanners need lower quantities of radiotracer for the same imaging outcome.

2) PET/MRI machines are free from the second component.

3) "Continuous FlowMotion" PET/CT machines lessen the irradiation exposure of the patient in comparison to their "Stop and Go" counterparts. This is the second best choice after 2).

I couldn't find the question I wrote until a few minutes ago. I have further questions about the PET/MRI. Below is what I wrote prior to finding my original question.

My questions now are the tracers used. Apparently, the answers I got were that the PET/MRI might be safer. Read below. These are my concerns. I really want to convince our oncologist to order the least harmful. I'm not sure why he would not order an MRI since we've had them before for doing spot radiation.

My husband has already had to PET/CT scans this year. One in May and one in August. I really don't want to weaken him further and I'm hoping to have his oncologist order an MRI.

When I spoke to him about my concerns he still felt a PET/CT was needed. They usually only do a pelvic and thoracic. This time I'd like a full body scan.

I'm going to have to have information to help convince our oncologist to do a less weakening scan/or less harmful scan. We cost Medicare next to nothing, since we aren't on Zytiga, or Xtandi or other expensive treatments.

We can't use iodine contrast (he's allergic) and we usually have done an MRI without gadolinium...

Can someone help me with information to help convince our doc to do an MRI. He's had them before. I don't understand why not now. The PET/CT isn't also correct. He has osteoarthritis that is sometimes placed in the category of bone mets. Yes he has bone mets, we know this.

We don't want a bone scan either. I know that Stanford has this machine. The PET/CT does use a trace though I'm reading that the PET/MRI uses less.

I really don't want to weaken my husband further.

Thanks very much for any information on this. I need to be able to make sense to our doc.

(this is something I just found)

Are There Any Risks From a PET/MRI Scan?

A PET/MRI scan is a safe test. There's no radiation from the MRI because no X-rays are used. Large amounts of radioactivity can be dangerous, but the amount used in a PET scan is very small, about the same as from flying cross-country three times.

[Hidden]

Hi Bluebird,

Do not confuse an ordinary MRI scanner (i.e the machine) with a PET/MRI one.

They are two entirely different kind of scanners.

The problem with the PET/MRI is that is not as commonly deployed as its counterpart the PET/CT.

Out the top of may head I would say that the latter outnumber the former by more than tenfold. Only top of the line hospitals MAY have one such scanner.

They are the top technology offerings today.

In your position I would emailed Siemens requesting info regarding the availability of such a scanner nearest to your home.

siemens-healthineers.com/ma...

I guess that you will have to travel to such a hospital, if this is possible for your husband.

My best wishes to you both.

[Bluebird11 in reply to Hidden]

Thanks. Our medical facility is 3 min away from a liaison hospital that has one. I’m wondering about Medicare covering it then. I have to research it. Is it something you would use in place of a Pet/Ct. thanks for the information.

[Hidden in reply to Bluebird11]

Yes, I would definitely would. I am an engineer and know that medical engineering moves at a tenfold faster pace forward than its clinical counterpart. Just have a look for the time and money it takes for the approval of a new or enhanced drug compared to some diagnostic or treatment equipment. The difference being the ability of engineering to provide measurable, documented and repeatable results in far-shorter periods.

Take for example what you have already stated, i.e. that a lesser concentration of contrast agent is required with MRI vs CT for an equivalent imaging outcome. It doesn't take a couple of years to unequivocally prove this. It simply works that way.

[j-o-h-n in reply to Hidden]

Breathe in........... Hold your breath........... Breathe...........

Good Luck, Good Health and Good Humor.

j-o-h-n Wednesday 03/11/2020 11:52 PM DST

[Tall_Allen]

This site has the worst search engine! I sometimes find stuff using the "site" command in google. In the google search bar, you enter the word "site:" followed by the url of the site, and then add any key words you can recall. Like:

site:healthunlocked.com/advanced... "Tall_Allen" "PET scan"

I probably gave you this link, which mentions PET/MRIs

pcnrv.blogspot.com/2016/12/...

Because there are only a few of those machines in the country (Stanford's is only one of a handful), I imagine there are long waiting lists to get access. If he can't take Iodine or Gadolinium, he will have to do it without contrast. In that case, why not use the PET/CT? (the radiation exposure is a non-issue unless this is a frequent event).

The bigger question is which radioindicator he will use in the PET scan.