Science has developed many ways to examine the internal body organs and their details, and a whole department of medical science has been dedicated to such examination called “Radiology.” Major methods used in Radiology include X-rays, Ultrasound, CT scan and MRI. Of all the above mentioned methods, safest and most modern one is MRI. It does not emit radiations; rather it works with a magnetic field system.
What does MRI stand for?
MRI is an abbreviated form of Magnetic Resonance Imaging. It is a non invasive diagnostic test that helps the physicians to diagnose the problem and ailment, and treat it accordingly.
How does MRI work?
It is important to note that our body is primarily composed of water molecules; each containing two hydrogen nuclei, or Protons. These protons align themselves in the process of an MRI scan.
The process uses a powerful Magnetic Field, radio frequency pulses, and a computer. A very strong magnetic field is created by passing an electric current through the wire loops. At the same time, other wire loops in the magnet send and receive radio waves.
This second radio frequency electromagnetic field is turned on for a brief period. Protons are triggered and they align themselves, absorbing some of the energy afterwards. Once this is done, the electromagnetic field is turned off. Molecules emit energy signals, which are caught by the coil. These signals are processed by a computer, generating an image. Finally, a 3D image is produced, which is the report of a n MRI scan.
How is an MRI scan performed? Let us know the procedure.
The patient if positioned on a movable table, and can be tied with straps to hold him still during the process, as it is vital not to move during an MRI scan, and maintain a correct position. Devices containing coils for receiving and sending radio waves are positioned around or adjacent to the patient. If needed, a contrast material may be inserted into the body for a better scan. The patient is moved into the MRI unit, and the doctors go out of the room until the process completes. You may require and ask for ear plugs to lessen the internal noise of the unit, and some scanners may be equipped with music to keep you entertained during the process.
- It is a non invasive imaging method, which does not involve exposure to radiation.
- This method generates better defined images and helps early diagnosis, more than any other technique.
- An abnormality which is hidden behind a bone and cannot be found with other techniques can be seen with MRI scan.
- Contrast injection is not necessary, and if used, it is less prone to produce allergic reactions that those used in X-ray and CT scan.
- If safety guidelines are adopted, this method poses almost no threat to an average patient.
- There are risks of excessive sedation, if sedation is used.
- The metal devices involved may hinder the process, or create malfunctioning.
- If contrast material is injected, a slight risk of allergy exists.
- Injecting high dose of MRI contrast material may result in Nephrogenic system fibrosis, in patients with poor kidney functions.
This is a uniquely effective and prone to fewer risks than other investigative methods adopted by Radiology. It generates better results with defined images and clearer pictures. It is surely a great gift of science to the mankind.