mri-240516053831-d6953aeb.pptx physicssss

mri

1. Magnetic Resonance Imaging ( MRI ) Presented By : Name : Reduan Ahmad ID : 232-35-016 Section: A Batch: 41

2. Who is the father of MRI ? Raymond Vahan Damadian (March 16, 1936 – August 3, 2022) was an American physician, and inventor of the first nuclear magnetic resonance (NMR) scanning machine.

3. Table of contents 01 04 02 05 03 Introduction How MRI works Components of MRI Equation Shape of MRI Machine

4. MRI : Big magnet and radio waves take picture inside our body , no radiation involved. Super clear body pictures, helps doctors see problems with out hunting us . Secret sauce of MRI , makes detailed pictures possible . Introduction 01

5. How MRI works Big magnet Radio waves Signal Picture

6. A superconducting magnet is the heart and most expensive part of an MRI scanner. Gradient coils are used to produce deliberate variations in the main magnetic field Components of MRI Superconducting Gradient coils

7. Components of MRI Gradiant coils Red coil – Create a varying magnetic field from left to right . Yellow coil – Create a varying magnetic field from top to bottom. Blue coil – Create a varying Magnetic field from head to toe.

8. Components of MRI RF Coils RF coils are the “antenna” of the MRI system They are simply a loop of wire either circular or rectangular . [ Radiofrequency]

9. Start RF pulses ( Excitation – Protons jump to higher energy state by absorbing radiation ). Each proton is rotating around its axis 63,000,000 rotation per second . The 63 MHz rotation is in the frequency range called Radio frequency.

10. Stop RF pulses (Relaxation – Protons return to their original state emitting radiation)

11. Equation   Here, ω is how fast spins move (in radians per second), γ is a constant for each atom type (gyromagnetic ratio), B is the magnetic field strength.  

12. Shape of MRI Machine Closed MRI Open MRI

13. Open MRI Closed MRI Open MRI : High field typically 1.5 T – 3 T ( Tesla) High Image quality Fast imaging Advance application Closed MRI : Low field typically 0.2 T – 0.4 T ( Tesla) Low image quality Slow imaging Limited application

14. Thank You