1- The patient is positioned within MRI scanner that form a strong magnetic field aroun the area to be imaged.
2-The high magnetic field causes the excitation of the protons in the tissues. containing water in the organ to be imaged.
3-The excited hydrogen atoms emit a radio frequency signals which is measured by a receiving coils.
4-The contrast between tissues is determined by the rate at which excited atoms return back to their equilibrium state.

 Notes
As the coils are rapidly switched on and off they creat the characteristics repetitive noise on an MRI scan.

MRI requires magnetic field that is both strong and uniform.

The standard display of MRI images is to represent fluids in black and white images.

MRI is in general a safe equipments although injuries may accur as a result of failed safety procedures or human errors.

Example for patients that can't use MRI
- Cardiac pacemaker
- Metallic foreign body in the eye
- Cochlear implants 

T1vsT2 images 
** The timing of radio frequency pulse sequence used to take T1 image results in an image which highlight fat tissues within the body.
** The timming of radio frequency pulse sequence used to make T2 images result in an image which highlight fats and water within the body.