Magnetic Resonance Imaging (MRI) Whatsapp Chat
WHAT IS AN MRI SCAN?
MRI stands for Magnetic Resonance Imaging. An MRI scan uses a strong magnetic field and radio waves to create pictures, on a computer, of tissues, organs and other structures inside your body. Magnetic resonance imaging (MRI) is a type of scan that uses strong magnetic fields and radio waves to produce detailed images of the inside of the body. An MRI scanner is a large tube that contains powerful magnets.
How does the Machine Scan?
- Human Body is made up of water to the extent of 97%. Water molecules are made up of protons(H+) which are nothing but small moving charged particles. These protons are have their own tiny magnetic field & behave like small bar magnets.
- Normally these protons are aligned randomly in a haphazard way. When you are placed in a MRI scanner, a strong magnetic field is applied which aligns these protons. All the protons line up in parallel to the magnetic field, like tiny magnets. (Same as what happens when you place multiple small magnets in close proximity to a large magnet).
- Then, short bursts of radio waves are sent from the scanner into your body. The radio waves knock the protons from their position. These radio waves are not radiation but are like the waves used in Bluetooth, radio stations, microwaves, cellular phones ect.
- When the burst of radio waves stops, the protons realign back into place. As they do so they emit radio signals. The protons in different tissues of the body realign at different speeds. Therefore, the signal emitted from different body tissues varies. So, for example, softer tissues can be distinguished from harder tissues on the basis of the signals sent.
- These signals are detected by a receiving device in the scanner.
- The receiving device transmits the signals to a computer. The computer creates a picture based on the radio signals emitted from the body.