MRI Test (MAGNETIC RESONANCE IMAGING)
TECHNOLOGY OF MRI Test
A magnetic resonance imaging (MRI) test is a common procedure used by hospitals around the world. An MRI Test utilizes a strong magnetic field and radio waves to create detailed images of various parts of the body e.g. spine, head, shoulder, knee, pelvis etc. MRI Test is a non-invasive and painless procedure. Unlike X-rays and CT scans, MRI Test uses magnetic radiation and not X-rays. It is hence considered a safer procedure.
Magnetic rays are attracted to water molecules in the body and hence MRI tests give images of tissues and organs. They do not give the images of the bones.
Various kinds of MRI test
1. MRI with contrast or MRI without contrast:
A contrast agent is injected in the body or given orally for MRI Test with contrast. This generally gives better images than MRI test without contrast. However, your doctor will be in a best position to decide which one to go for.
2. Closed vs. open MRI Test:
Most MRI Test machines require the patient to lie down and go into a machine. For people who are claustrophobic (fear closed spaces), this may cause anxiety. The technician can give sedatives in those cases. Another alternative is to opt for an open MRI test which is more expensive but will not cause anxiety. Many children may feel anxious and hence may need to be given sedatives.
Tesla is a unit of measurement of magnetic strength. MRI machines can either be 1.5 tesla or 3 tesla. A 3 Tesla MRI Test machine can produce better quality images at a faster pace. However, they are more expensive. Additionally, for most of the MRI tests that are done in India, the 1.5 Tesla machines are adequate.
4. Noiseless MRI Test:
Usually conducting an MRI test is a noisy affair. However, new MRI machines can help drown the noise. If you want a noiseless experience, please check with your friendly advisor at labsadvisor.com
5. Screening vs. normal MRI Test:
Depending on the details required for the organ tested, the doctor may recommend a screening or a normal MRI test. The default is normal. Screening MRI test is less expensive and details are slightly less.
Procedure of MRI Tests
The MRI machine looks like a tube that has both ends open. You lie down on a movable table that slides into the opening of the tube. A technologist monitors you continuously.
Before the exam you will be asked to fill out a screening form asking about anything that might create a health risk or interfere with imaging. Items that may create a health hazard or other problem during an MRI test exam include:
- Cardiac pacemaker or implantable defibrillator
- Catheter that has metallic components that may pose a risk of a burn injury
- An implanted or external medication pump (such as that used to deliver insulin or a pain-relieving drug)
- A cochlear (inner ear) implant
Items that need to be removed by patients and individuals before entering the MRI test system room include:
- Purse, wallet, money clip, credit cards, cards with magnetic strips
- Electronic devices such as beepers or cell phones
- Hearing aids
- Metal jewellery, watches
- Pens, paper clips, keys, coins
- Hair barrettes, hairpins
- Any article of clothing that has a metal zipper, buttons, snaps, hooks, underwire, or metallic threads
- Shoes, belt buckles, safety pins
Objects that may interfere with MRI test image quality if close to the area being scanned include:
- Metallic spinal rod
- Plates, pins, screws, or metal mesh used to repair a bone or joint
- Joint replacement or prosthesis
- Metallic jewellery including those used for body piercing
- Some tattoos or tattooed eyeliner.
- Makeup, nail polish or other cosmetic that contains metal
- Bullet, shrapnel, or other type of metallic fragment
- Metallic foreign body within or near the eye (such an object generally can be seen on an x-ray; metal workers are most likely to have this problem)
During the MRI test, the internal part of the magnet produces repetitive tapping, thumping and other noises. If you are worried about feeling claustrophobic inside the MRI machine, talk to your doctor beforehand. You may receive a sedative before the scan. MRI scan can also be done in an open MRI machine which is generally more expensive.
In some cases, a contrast material may be injected through an intravenous (IV) line into a vein in your hand or arm. The contrast material enhances the appearance of certain details. The material used for MRIs is less likely to cause an allergic reaction than the material used for CT scans.
An MRI can last up to 45 minutes or more. You must hold very still because movement can blur the resulting images.
Risks with MRI Tests
MRI does not use ionizing radiation (high-energy radiation that can potentially cause damage to DNA, like the x-rays used CT scans).
There are no known harmful side-effects associated with temporary exposure to the strong magnetic field used by MRI scanners.
If you want to get an MRI test done, you may check out the following links