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Author Topic: What is the difference between a CT Scan and an MRI scan?  (Read 281923 times)

Offline lancenti

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #25 on: 05/02/2009 10:07:23 »
Blasting radiation into yourself was never a safe thing. Neither was eating purified radioactive material.

Though I don't see how an MRI could do that. If I understand correctly, it functions like an NMR which just works on changing the spin of protons. Come to think of it, are the MRI Machines in hospitals Carbon, Phosphorus or Hydrogen NMRs? I figure it'd be one of these three since these are most abundant.
 

Offline Karen W.

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #26 on: 05/02/2009 10:28:57 »
I don"t know.. but I had so many iodized cat scans and exrays and such that they said I was at the limit.. so I just had another and my doctor was worried because she said She had hoped she did the right test as she doesn't want me having too much yet.. I guess there is some kind of time frame and limit before trouble..I really don't understand..
 

Offline Counterpoints

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #27 on: 09/06/2009 19:34:11 »
Blasting radiation into yourself was never a safe thing. Neither was eating purified radioactive material.

Though I don't see how an MRI could do that. If I understand correctly, it functions like an NMR which just works on changing the spin of protons. Come to think of it, are the MRI Machines in hospitals Carbon, Phosphorus or Hydrogen NMRs? I figure it'd be one of these three since these are most abundant.

As far as the scientific community is concerned, there are absolutely no known negative after-effects of MRI.  I know MRI researchers who have had over 100 MRI scans done on themselves.  It is basically harmless, as far as we know.

On the other hand, this is NOT true of CT.  The radiation from a typical CT scan can be equivalent to hundreds of typical chest x-rays.  You do not want to have CT unless it is absolutely necessary. If I had a choice between MRI and CT, I would always opt for MRI.
« Last Edit: 09/06/2009 19:38:59 by Counterpoints »
 

Offline Counterpoints

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #28 on: 09/06/2009 19:36:45 »
I don"t know.. but I had so many iodized cat scans and exrays and such that they said I was at the limit.. so I just had another and my doctor was worried because she said She had hoped she did the right test as she doesn't want me having too much yet.. I guess there is some kind of time frame and limit before trouble..I really don't understand..

Karen, I would look into getting MRI from now on, instead.  It's relatively harmless compared to CT.  They may be more reluctant to order MRI just because it may cost the medical system a little more than CT.  I don't think this is a good reason though, when we're talking about your health.

As far as I know, with CT, it's the cumulative radiation (e.g. the number of scans you've had in total) that matters, not the amount of time that elapses between scans.  The time concern probably has more to do with iodine.  (e.g. to rest your kidneys before giving you more contrast).
 

Offline ScanMan

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #29 on: 22/06/2009 22:41:40 »
Does anyone know what Neuro Vascular Digital Subtraction is??
 

Offline RD

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Offline Karen W.

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #31 on: 27/06/2009 19:49:26 »
I don"t know.. but I had so many iodized cat scans and exrays and such that they said I was at the limit.. so I just had another and my doctor was worried because she said She had hoped she did the right test as she doesn't want me having too much yet.. I guess there is some kind of time frame and limit before trouble..I really don't understand..

Karen, I would look into getting MRI from now on, instead.  It's relatively harmless compared to CT.  They may be more reluctant to order MRI just because it may cost the medical system a little more than CT.  I don't think this is a good reason though, when we're talking about your health.

As far as I know, with CT, it's the cumulative radiation (e.g. the number of scans you've had in total) that matters, not the amount of time that elapses between scans.  The time concern probably has more to do with iodine.  (e.g. to rest your kidneys before giving you more contrast).

I am sorry that I missed this post.. thank you for the information . Its been a long while now but as you said with this information and my further talking with the doctor, it was indeed more cat scans and regular exrays they were worried about, I had taken her comments as being about  MRI's in particular, when she was telling me about all the exrays cat scans and MRI's. Turns out I had had Far too many exrays ct scans etc.... between all the different Doctors.
 Thanks....
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #32 on: 28/06/2009 17:29:57 »
I don"t know.. but I had so many iodized cat scans and exrays and such that they said I was at the limit.. so I just had another and my doctor was worried because she said She had hoped she did the right test as she doesn't want me having too much yet.. I guess there is some kind of time frame and limit before trouble..I really don't understand..

Karen, I would look into getting MRI from now on, instead.  It's relatively harmless compared to CT.  They may be more reluctant to order MRI just because it may cost the medical system a little more than CT.  I don't think this is a good reason though, when we're talking about your health.

As far as I know, with CT, it's the cumulative radiation (e.g. the number of scans you've had in total) that matters, not the amount of time that elapses between scans.  The time concern probably has more to do with iodine.  (e.g. to rest your kidneys before giving you more contrast).

I am sorry that I missed this post.. thank you for the information . Its been a long while now but as you said with this information and my further talking with the doctor, it was indeed more cat scans and regular exrays they were worried about, I had taken her comments as being about  MRI's in particular, when she was telling me about all the exrays cat scans and MRI's. Turns out I had had Far too many exrays ct scans etc.... between all the different Doctors.
 Thanks....

No problem.  If they'd like to do another CT/CAT scan, I'd ask about MRI.  MRI scans are kind of fun, in my weird opinion. ;)

 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #33 on: 29/06/2009 07:46:53 »
They are ok.. but the noise was awful. Towards the end my arm felt as if the insides were moving around on my left arm.. It was odd! The music they put on was totally inaudible over the pounding  of the machine. I go for another Ct Scan in September. At least thats what Stanford has said!
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #34 on: 29/06/2009 07:50:23 »
Do you think there is anything to this..?

http://www.gadolinium-mra.com/?gclid=COKz3v3wrpsCFQITswodvArJCA

 I just saw the ad here in the forum!
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #35 on: 29/06/2009 08:06:19 »
Do you think there is anything to this..?

http://www.gadolinium-mra.com/?gclid=COKz3v3wrpsCFQITswodvArJCA

 I just saw the ad here in the forum!

Gadolinium is the contrast they use in MRI. It isn't always needed though.  If there is no gad contrast, MRI (as far as we know) is completely safe, so long as you don't have metal in your body, or a pacemaker, etc.

An MRI with gad contrast is also relatively safe.  The contrast is considered safer than the iodine used in CT, with a very small percentage (about 0.03%-.1%) having serious allergic reactions.  The risk they're talking about is nephrogenic systemic fibrosis, which from what I've read, is extremely rare and has only been associated with people who have severe kidney impairment (for instance, those in need of dialysis).   If you do have kidney problems though, it is something to discuss with the doctor before having GAD contrast with an MRI.
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #36 on: 29/06/2009 08:10:06 »
They are ok.. but the noise was awful. Towards the end my arm felt as if the insides were moving around on my left arm.. It was odd! The music they put on was totally inaudible over the pounding  of the machine. I go for another Ct Scan in September. At least thats what Stanford has said!

Hmm... I wonder if MRI could be used instead.  MRI is usually more detailed than CT.

The noise can be a pain.  Siemens is making some really nice MRI machines these days, which are quieter, faster and sometimes have more space too.  (I'd be cautious about "Open" MRI though, since truly Open MRI doesn't make very good images... an exception is the Siemens Magnetom Espree, which I don't consider "open bore", even though it is advertised that way).
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #37 on: 29/06/2009 08:43:52 »
I am not sure why.. but when I spoke with the nurse last week she did say it was an CT scan they were setting up. Couldn't hurt to ask I guess. They will be taking measurements and looking at two anuerysms in the Aorta and checking the valves etc.. I have to have them all replaced coming up.

The doctor said to me that after the surgery he can give me five years maybe ten...Is that a common time frame for replacement of all that stuff and dealing with the aneurysms? So what kind of a time frame does one have if I were to refuse the surgical replacements/do you know what the statistics are for that?
Is it worth 5 years? Will the distress and healing of surgery out weigh the gift it gives..?
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #38 on: 29/06/2009 08:46:27 »
Do you think there is anything to this..?

http://www.gadolinium-mra.com/?gclid=COKz3v3wrpsCFQITswodvArJCA

 I just saw the ad here in the forum!

Gadolinium is the contrast they use in MRI. It isn't always needed though.  If there is no gad contrast, MRI (as far as we know) is completely safe, so long as you don't have metal in your body, or a pacemaker, etc.

An MRI with gad contrast is also relatively safe.  The contrast is considered safer than the iodine used in CT, with a very small percentage (about 0.03%-.1%) having serious allergic reactions.  The risk they're talking about is nephrogenic systemic fibrosis, which from what I've read, is extremely rare and has only been associated with people who have severe kidney impairment (for instance, those in need of dialysis).   If you do have kidney problems though, it is something to discuss with the doctor before having GAD contrast with an MRI.
definitely having Kidney problems.. as a matter of fact they will be checking that right before the schedueled CT scan!
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #39 on: 29/06/2009 09:23:20 »
I am not sure why.. but when I spoke with the nurse last week she did say it was an CT scan they were setting up. Couldn't hurt to ask I guess. They will be taking measurements and looking at two anuerysms in the Aorta and checking the valves etc.. I have to have them all replaced coming up.

The doctor said to me that after the surgery he can give me five years maybe ten...Is that a common time frame for replacement of all that stuff and dealing with the aneurysms? So what kind of a time frame does one have if I were to refuse the surgical replacements/do you know what the statistics are for that?
Is it worth 5 years? Will the distress and healing of surgery out weigh the gift it gives..?

When would your surgery be?  I can't answer these questions, but I can try get an opinion.  I imagine it largely depends on your specific situation.  Was it the surgeon who told you this, or your family practitioner? Have you tried asking these questions to either of them?
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #40 on: 29/06/2009 09:30:36 »
THE CARDIOLIGIST/SURGEON.

I do not know yet! That is one of the reasons for tests.. more CT scans etc..

Sorry I just thought you might know if that was about standard life expectancy after these kinds of surgeries. It's ok.. I cannot find any real sound stats on it  although the ones I did find were vague.
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #41 on: 29/06/2009 09:47:34 »
THE CARDIOLIGIST/SURGEON.

I do not know yet! That is one of the reasons for tests.. more CT scans etc..

Sorry I just thought you might know if that was about standard life expectancy after these kinds of surgeries. It's ok.. I cannot find any real sound stats on it  although the ones I did find were vague.

Makes sense.   

My instinct would be to trust the surgeon (and to ask him when you can), but it doesn't hurt to get opinions from some other physicians. Perhaps your family doctor could help you get in touch (or more likely could get himself in touch) with another surgeon, or specialist, who can help give you some stats in the context of your situation.

I'll keep my fingers crossed for you! :) 

It's very hard to advise, but try not to spend too much time worrying, and do some things you enjoy. Stress definitely contributes to our health problems. I spend way too much time worrying myself!!
« Last Edit: 29/06/2009 09:49:49 by Counterpoints »
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #42 on: 29/06/2009 09:59:15 »
 We all do.. each and every one of us, but it helps to have a handle on the details so one can prioritize and be proactive in there own healing.. then the important things can be handled and taken care of for family and such.

I hope your worries are few and you are happy too.

Thanks for those crossed fingers...and the advice and opinions. Hell! Thanks for the conversation!
 

Offline Counterpoints

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What is the difference between a CT Scan and an MRI scan?
« Reply #43 on: 29/06/2009 20:08:45 »
My pleasure, and good luck!  Your questions are very good.
« Last Edit: 29/06/2009 20:31:27 by Counterpoints »
 

Offline Karen W.

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What is the difference between a CT Scan and an MRI scan?
« Reply #44 on: 30/06/2009 11:27:38 »
Thank you!
 

Offline Lorie

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What is the difference between a CT Scan and an MRI scan?
« Reply #45 on: 28/10/2011 05:40:54 »
I can't find how to start a new topic so I am replying to this topic. I have had a lot of problems and pain this week in my lower stomach (where I suspect my ovaries would be). It started Monday when I had a gush of blood accompanied by pain. The Dr said I had a cyst burst and sent me home with no tests done. The following day I was in so much pain so I went back to emerg and they kept me there all day. The Dr on call was the same Dr whom I seen the first time he ran a X-Ray, Ultra Sound and a Ct scan and found nothing. I'm still in a lot of pain and the pain has spread from my lower stomach to shooting down my right leg and my lower to mid back now. Will a MRI show things these other tests couldn't?
 

Offline grizelda

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What is the difference between a CT Scan and an MRI scan?
« Reply #46 on: 28/10/2011 06:58:48 »
It's probably better to learn sooner rather than later to avoid X-rays of any kind if at all possible.
 

Offline rperry81

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #47 on: 29/05/2012 12:32:40 »
I know this post is old, but I was reading in here and ppl was talking about this drink they have to drink etc.....that drink is for a colon test basically and you have to drink something special for it, I found this out from a lady i worked with her brother had to do it and have tests ran for colon cancer
 

Offline rperry81

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #48 on: 29/05/2012 13:00:34 »
I can't find how to start a new topic so I am replying to this topic. I have had a lot of problems and pain this week in my lower stomach (where I suspect my ovaries would be). It started Monday when I had a gush of blood accompanied by pain. The Dr said I had a cyst burst and sent me home with no tests done. The following day I was in so much pain so I went back to emerg and they kept me there all day. The Dr on call was the same Dr whom I seen the first time he ran a X-Ray, Ultra Sound and a Ct scan and found nothing. I'm still in a lot of pain and the pain has spread from my lower stomach to shooting down my right leg and my lower to mid back now. Will a MRI show things these other tests couldn't?


If all those tests were ran and it came back nothing then my suggestion to you if this has not been taken care of yet because it has been a year ago, is to go to a regular primary care doctor because ER doctors only run tests and look for certain things not the whole problem, if nothing was seen then for sure follow up with a OB doc and have them run your ultrasound and further tests! I have experienced this myself and I was told by my OB doctor that I have what is called varicous veins in the legs well I have that in the uterus and what happens is it swells up with inflammation right before the period comes and is to much blood flow in the uterus and can stay through out the menstrual and really there is nothing to do about it other then hysterectomy OR if you are bleeding constantly and non stop they have a procedure out that I just learned about it is called NovaSure and they do this which stops menstrual altogether ( newbielink:http://en.wikipedia.org/wiki/Endometrial_ablation [nonactive]) to avoid hysterectomies. The other thing is I'm sure you found out by now what it is, but it could have been a tubal pregnancy even though they ran an ultrasound maybe they did not detect it yet, did they run a pregnancy test? I'm sure they did if they ran xrays they have to. Have you had kids before? Another pain that can be happening is from having kids is a prolapse bladder, I went into the ER from this pain and they ran a CT on me because I was complaining of these pains and they wanted to check my gallbladder on a CT and other organs it all came back normal of course and they did pelvic exam and he tells me I don't see no prolapsing going on etc..., etc......well first off I knew he was crazy because my ob had just told me I had this, and I just recently went to another OB and was diagnosed with prolapse and the extra blood flow in uterus! So see don't always trust ER they are good to help the pain some and run test but not to look at the whole picture! Another thing that could be going on with you is if you have had kids also is an umbilical hernia of the belly navel, I have that and have to have surgery for them to correct it because it flares up and swells up and it pulls and tugs and gets caught up in there and I can't stretch my abdomen area because it will hurt like hell and shoot pains as will the prolapse even with intercourse and as the extra blood flow in uterus. The last and final thing is it could be your sciatic nerve those can cause lower abdomen pain and shoot into the legs and you also have what is called round ligaments in there and those stretch like a rubber band from and with pregnancies and when pregnant a baby will basically bing them back and forth and they hurt like HELL also, I've had that with 2 of my children. I'm curious to know if you found out what was causing your pain so if you get this message please write back, I'm very interested in knowing what your cause of pain was???? Thanks!
 

Offline cheryl j

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #49 on: 30/05/2012 01:16:00 »
A CT is basically the same thing as an xray, but allows multiple views or cross sections, but uses the same the same technoolgy as an xray, and exposes the patient to radiation. An MRI is basically a giant magnet the creates an image based on the polarity of protons in water molecules in the body. It does not expose the patient to radiation. MRIs are better for looking at soft tissue, and are more useful for finding tumors than CTs in some body organs.
 

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Re: What is the difference between a CT Scan and an MRI scan?
« Reply #49 on: 30/05/2012 01:16:00 »

 

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