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Medical MRI better than CT scan?

  1. Feb 15, 2013 #1
    In the case of detecting muscle damage, would there be any reason to choose a CT scan over MRI? I know MRI takes longer and can be more expensive, but the CT scan radiation seems to be high enough to try and avoid it if possible. fyi, I am in communication with a doctor, but he's taking ages to get back to me :)
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  3. Feb 15, 2013 #2


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    We can't dispense medical information on PF :tongue: but I know which one I'd prefer.
  4. Feb 15, 2013 #3


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    You're not planning to have a CT scan every week right? I don't think you need to worry about the radiation. I don't know which one would be better, the radiologist should know :)
  5. Feb 17, 2013 #4
    depends on where you are.

    in canada, waitlists for MRIs are insanely long. they're also more expensive, meaning that doctors may be reluctant to designate government allocated funds for minor problems.

    like the above poster said, the rad exposure is negligible.

    the exact amount depends on what region you're getting scanned.

    there's a handy little table on the wiki page for comparison:


    it states that avg environmental rad dose is 2.4msv..... you can compare that to the dose you'll recieve for a specific body part.
  6. Feb 17, 2013 #5


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  7. Feb 17, 2013 #6


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  8. Feb 17, 2013 #7


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  9. Feb 17, 2013 #8
    Thanks all! Gives me good ammo to bring to my doctor! The region is my very lower abdomen. I believe I have a sports hernia (too much soccer).
    This is very close to my "sensitive organs", so I don't need any ionized radiation down there :D
  10. Feb 17, 2013 #9


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    Some persons in this thread regard the radiation dose of a CT scan as negligible.
    This is certainly not true. CT scans make up for most of the diagnostic medical radiation dose in the general population and the dose received in one CT is -depending on the scan - equivalent to several years of natural radiation dose. Already now the dose due to medical examinations in industrialized countries is higher than the natural radiation and this is mainly due to CT examinations.
    The general rule in radiation protection is called "ALARA", "as low as reasonably achievable" whence at least I would avoid a CT if alternative techniques are available.
    Furthermore, to detect a damage in soft tissue, MRT is usually preferable.

    The German Federal Office for Radiation Protection has a nice brochure on radiation burden of medical examinations. Although it is in German, the diagrams may be informative to non-German speakers, too:
    http://www.bfs.de/en/bfs/publikationen/broschueren/ionisierende_strahlung/medizin/STTH_Roentgen.pdf [Broken]
    There's also a similar but shorter text in English:
    http://www.bfs.de/en/bfs/publikationen/broschueren/ionisierende_strahlung/medizin/BRO_Roentgen_Nutzen_und_Risiko_eng.pdf [Broken]

    You can see that in particular CT scans of the abdomen go in hand with quite high doses of 8 to 20
    Last edited by a moderator: May 6, 2017
  11. Feb 20, 2013 #10
    Am I right in thinking radiation dosage is cumulative over ones lifetime?
    If so would it be possible to put an average dosage figure on say someone of the age of 70 ? (randomly chosen age - no specific reason)
  12. Feb 20, 2013 #11
    I would defer to the doctor's discretion as he/she should know what he's looking for and how he best may find that. The only caveat is that I'd make sure his decision in no way reflected some sort of financial conservatism.
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