Basic Principles of MRI

                                 

Strong magnetic field

       Spin up         

                                                        

                                                                       Emitted Photon

*  The spin-up and spin-down nuclei have different energies.

* In a magnetic field, spinning nuclei precess at the Larmor frequency.

HOW CAN WE SEE HUMAN BRAIN BY MRI??

What is the Basic Principles of X-ray CT??

* A benchmark tube produces X-rays with an power of approximately 150 keV.

* A fan-shaped beam passes through the persevering and is detected to pattern a projection.

* The source and detector are rotated to get a bigger number of different projections.

* Images are reconstructed utilising a method called back projection and give a measure of the X-ray attenuation coefficient at every point.

X-ray CT Pictures of the Head and Abdomen

* Air is dark

* Bone shows bright

* Different densities of tissue give intermediate results