In the medical world before your physician starts your treatment he would ask you to do various tests to detect, diagnose, or monitor disease, disease processes and if you are on medication then to check the improvement. Those tests include Echocardiography, Complete Blood Count (CBC), X-rays, ACTH, MRI, CAT or CT scan, etc.
Amongst all, MRI and CT scan are common and prominent for serious diseases or injuries these days. There is a vast difference between these tests though both provide detailed pictures inside of your body, which would be described further.
The difference in the technique used
A Computerized Tomography (CT) scan uses X-ray technology at different angles to produce cross-sectional diagnostic images of the body. Here they use PC to produce images from X-rays.
Whereas in Magnetic Resonance Imaging (MRI) powerful magnetic field and radio waves are used to produce detailed images.
Which one is safer?
Very open design of the CT scan machine gives patients relief although the narrow tube of the MRI machine causes anxiety or Claustrophobia. Advancement in technology designed open MRI for those patients not comfortable with the narrow tube.
What do they diagnose?
CT scans are mostly used to examine;
- Bone injuries
- Assist to differentiate between an ischemic or hemorrhagic stroke
- Trauma particularly facial trauma
- Abnormalities in the lungs or chest
- Detect tumors
MRI used to examine;
- Soft tissue injuries specifically in ligaments or tendons
- View spinal cord injuries
- Examine brain tumors
- Diseases of the liver, bile ducts, pancreas, etc are examined
- Pelvic pain in women
MRI gives greater details which are difficult through CT scan, especially of the soft tissues surrounding the bones.
The difference in time taken during the test
To be expected MRI takes more time than a CT scan. MRI takes an average 30 min to two hours while the CT scan takes less than 5 min depending on the area that is being scanned or examined.
Limitations for both
Patients having weight 300-500 pounds are difficult to handle on usual CT scan, as an alternative they have to be sent to a location with a table designed where patients of their kind are handled. However, though the size of the MRI tube also has a limit such patients are handled with the open MRI machine.
Patients with metal implants or tattoos can get a CT scan. But in the case of MRI since the magnetic field is used metal implants or tattoos are strictly not permitted.
CT scans are used during emergency situations since MRI takes time to give detailed pictures of it. Since CT scan is limited in detail, MRI is also prescribed to be done after CT scans.
Both show cross-sectional images of the body, though the techniques they use are different as well they are painless.
It would not be your choice which tests you will go through. It is absolutely your physicians’ decision. Beside the point, there is no danger all around during any of these tests. So, next time when you will go along with anybody just relieve them.
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