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Here in NZ an Australia, the college of radiologists disagree and say ‘don’t do it’ for screening the worried well. https://www.ranzcr.com/college/document-lib

Here in NZ an Australia, the college of radiologists disagree and say ‘don’t do it’ for screening the worried well. https://www.ranzcr.com/college/document-library/2024-position-statement-on-whole-body-mri https://www.ranzcr.com/college/document-library/2024-positio...

mgraczyk 9mo ago
Seems like their main concern is "substantial downstream healthcare costs"
- lostlogin 9mo ago
  Yes, and needless biopsy can be a big deal. It’s a great document, I’m an MR tech and we now have something to lean on when we say no to these scans. We can then scan people with problems rather than people with too much money.
  - mgraczyk 9mo ago
    Great document? I just read the entire thing, it contains no evidence or justification for their claims. > We can then scan people with problems rather than people with too much money. Right, this is what it's really about. MRIs are a scare resource and providers need to manage cost. Fortunately I can afford to pay out of pocket, but I'm just annoyed that doctors are so irrational about this To be clear, it's up to a doctor whether or not to do a "needless biopsy". That has nothing to do with a scan.
    - lostlogin 9mo ago
      … they do it based on the scan result. Avoiding a biopsy that wasn’t needed is a good thing.
      - mgraczyk 9mo ago
        You're imagining that the doctor is required to act irrationally or against the patient's interest. I understand that they do act this way, but I'm pointing out that they don't have to! You walk into a doctor's office and meet for the first time. Case 1. You have 3 full body MRIs taken 6 months apart in hand and give them to your doctor. Nobody has opened or looked at the scans yet. Case 2. You do not have a scan yet You are claiming case 1 will lead to worse outcomes in expectation. I claim that's impossible because the doctor can simply do the following: Without opening the scans, email them to the world's best radiologist. Tell that radiologist "only reply if it is nearly certain the patient has an operable cancer with the information available" Now there are 4 possibilities. Case 1 without cancer: nothing happens Case 2 without cancer: nothing happens Case 1 with cancer: you maybe survive Case 2 with cancer: you die The only reasonable objection to this is "that's expensive"
        lostlogin 9mo ago
        A whole body MRI is low resolution and thick slices, they are crap. Instead you could get thin slices at high resolution of a body site that has issues or is suspected to have them. Do that instead. Whole body MR is 5-8mm thick slices at low in-plane resolution. A whole body scan has about 512 pixels over a 50-60cm field of view. Usually it’s even less pixels than this. Something like a knee, or brain is 2-3mm slices, and high in-plane resolution. A knee is 512 or even 720 pixels over 14cm. It’s vastly better. The difference is stark. A liver scan or other abdominal organ is lower resolution than a joint or brain, but unlike whole body MR is scanned in multiple planes with multiple image weighting (t1 in/out/fat sat, diffusion, t2, t2fs, gadolinium contrast). A liver scan has thin slices. Whole body scans generally do two coronal images (stir and t1) then call it quits.
        mgraczyk 9mo ago
        Yes the machines should definitely get better, but I recommend you do get it if the cost it truly zero. Based on the data in the article it is still worth it despite the low resolution!
        9mo ago
tjpnz 9mo ago
NZ doesn't have the screening capacity for when it's medically necessary, much less optional.

mgraczyk 9mo ago

Seems like their main concern is "substantial downstream healthcare costs"

lostlogin 9mo ago
Yes, and needless biopsy can be a big deal. It’s a great document, I’m an MR tech and we now have something to lean on when we say no to these scans. We can then scan people with problems rather than people with too much money.
- mgraczyk 9mo ago
  Great document? I just read the entire thing, it contains no evidence or justification for their claims. > We can then scan people with problems rather than people with too much money. Right, this is what it's really about. MRIs are a scare resource and providers need to manage cost. Fortunately I can afford to pay out of pocket, but I'm just annoyed that doctors are so irrational about this To be clear, it's up to a doctor whether or not to do a "needless biopsy". That has nothing to do with a scan.
  - lostlogin 9mo ago
    … they do it based on the scan result. Avoiding a biopsy that wasn’t needed is a good thing.
    - mgraczyk 9mo ago
      You're imagining that the doctor is required to act irrationally or against the patient's interest. I understand that they do act this way, but I'm pointing out that they don't have to! You walk into a doctor's office and meet for the first time. Case 1. You have 3 full body MRIs taken 6 months apart in hand and give them to your doctor. Nobody has opened or looked at the scans yet. Case 2. You do not have a scan yet You are claiming case 1 will lead to worse outcomes in expectation. I claim that's impossible because the doctor can simply do the following: Without opening the scans, email them to the world's best radiologist. Tell that radiologist "only reply if it is nearly certain the patient has an operable cancer with the information available" Now there are 4 possibilities. Case 1 without cancer: nothing happens Case 2 without cancer: nothing happens Case 1 with cancer: you maybe survive Case 2 with cancer: you die The only reasonable objection to this is "that's expensive"
      - lostlogin 9mo ago
        A whole body MRI is low resolution and thick slices, they are crap. Instead you could get thin slices at high resolution of a body site that has issues or is suspected to have them. Do that instead. Whole body MR is 5-8mm thick slices at low in-plane resolution. A whole body scan has about 512 pixels over a 50-60cm field of view. Usually it’s even less pixels than this. Something like a knee, or brain is 2-3mm slices, and high in-plane resolution. A knee is 512 or even 720 pixels over 14cm. It’s vastly better. The difference is stark. A liver scan or other abdominal organ is lower resolution than a joint or brain, but unlike whole body MR is scanned in multiple planes with multiple image weighting (t1 in/out/fat sat, diffusion, t2, t2fs, gadolinium contrast). A liver scan has thin slices. Whole body scans generally do two coronal images (stir and t1) then call it quits.
        mgraczyk 9mo ago
        Yes the machines should definitely get better, but I recommend you do get it if the cost it truly zero. Based on the data in the article it is still worth it despite the low resolution!
        9mo ago

tjpnz 9mo ago

NZ doesn't have the screening capacity for when it's medically necessary, much less optional.