SUBMITTED TO :
DR. NAVEED AHMAD
SUBMITTED BY :
USAMA YOUSAF
BSF1800372
BS PHY (VII) EVE
UNIVERSITY OF EDUCATION , COLLEGE ROAD
TOWNSHIP , LAHORE.

MRI :
→ Introduction
→Components
→Working & Principle
→Merits
→Demerits

Introduction:
.MRI is the abbrivation of magnetic resonance imaging .
.MRI is basically an imaging technique in which we get the
image of body’s soft tissues and organs for their internal study.
.This technique uses two concepts Magnetization and
Radio waves.

Components :
MRI machine has three major components .
→ Radio Frequency Coils (RF coils)
→ Gradient Coils
→ Magnets ; which produce magnetic field that is 30000 times
than that of earth.

Working & principle
As we know 60-70 % human’s body consists of water so,
protons are present in the shape of hydrogen atom in water
molecule .
Here is the position of protons when
there is no magnetic field.
When we switch on the magnetic field, the
proton are arranged in the direction of magnetic field.

When radio waves are switched on then there is phase change
of protons of 90 or 180 degree.
When radio waves are switched off then protons return to
their real equilibrium position and hence protons emit
photons of particular frequency and energy , collector collects
data and make image of particular tissue on moniter .

MERITS
→Functional image in any plane
→Non-Ionizing
→Non-harmful
→ Clear & high resolutionized image

Demerits
→ Too much expensive
→ Time consuming
→ Can’t be recommended for cardiac pacemakers and
who have metal plates in the case of bone fracture or
surgery.