1. Felix Bloch and Edward Purcell independently discovered nuclear magnetic resonance in 1946, which led to the development of NMR and its use for molecular analysis between 1950-1970. 2. In 1971, Raymond Damadian showed tissues and tumors had differing nuclear magnetic relaxation times, motivating the use of magnetic resonance for disease detection. He then spent seven years creating the first MRI machine. 3. The first commercial MRI was introduced in 1980 by FONAR and MRI continued developing, including the creation of open MRI machines and use of surface coils to optimize imaging of specific regions.

1. DR SAKHER-ALKHADERI
CONSULTANT RADIOLOGIST AMC

2. "Felix Bloch and Edward Purcell, both of whom were
awarded the Nobel Prize in 1952, discovered the
nuclear magnetic resonance (NMR) phenomenon
independently in 1946. In the period between 1950 and
1970, NMR was developed and used for chemical and
physical molecular analysis. In 1971 Raymond Damadian
showed that the nuclear magnetic relaxation times of
tissues and tumors differed, thus motivating
scientists to consider magnetic resonance for the
detection of diseases. Dr. Damadian and his team
spent the next seven years diligently designing and
creating the first MRI machine for medical imaging of
the human body."
MRI HISTORY
FONAR introduced the world's first commercial MRI (a whole-body MRI scanner)
in 1980, and went public in 1981.

4. The first MRI images produced by the machine .

5. 1977
Modern MRI

6. TYPES OF MRI

8. The OPEN MRI's started to come into production . The initial intent was to provide a
tool to perform the MRI diagnostic testing for patients that were a) Claustrophobic
or 2) Too obese to fit into the Closed models.

11. Neutral Flexion
Dynamic MRI

14. Surface Coils.
Surface coils are designed to provide a very high RF sensitivity over a small reg
interest. These coils are often single or multi-turn loops which are placed direct
the anatomy of interest. The size of these coils can be optimized for the specifi
region of interest.

20. MRI : WHAT IS
THE EXACT
PRINCIPLE

26. RADIOFEQUENCY

28. TURN OFF

29. Camera

30. SO TO GET AN IMAGE WE NEED

31. THE SIGNAL IS DISPLAYED ON GREY SCALE

32. AND ACCORDING TO THE RELAXATION TIME WE GET

40. Dark signal on all sequences

43. SPECIAL MRI SEQUENCES

50.  Diffusion weighted imaging (DWI) is a form of MR
imaging based upon measuring the random
Brownian motion of water molecules within a
voxel of tissue. The relationship between histology
and diffusion is complex, however generally
densely cellular tissues or those with cellular
swelling exhibit lower diffusion coefficients, and
thus diffusion is particularly useful in tumour
characterisation and cerebral ischaemia.

51.  DW imaging has a major role in the following clinical
situations 3-5:
 early identification of ischemic stroke
 differentiation of acute from chronic stroke
 differentiation of acute stroke from other stroke mimics
 differentiation of epidermoid cyst from arachnoid cyst
 differentiation of abscess from necrotic tumors
 assessment of cortical lesions in CJD
 differentiation of herpes encephalitis from diffuse temporal
gliomas
 assessment of the extent of diffuse axonal injury
 grading of gliomas and meningiomas (need further study)
 assessment of active demyelination

53. EPIDERMOID CYST

57. Functional magnetic resonance
imaging or functional MRI (fMRI) is
a functional neuroimaging procedure
using MRItechnology that measures brain activity by
detecting associated changes in blood flow.[1][2] This
technique relies on the fact that cerebral blood flow
and neuronal activation are coupled. When an area of
the brain is in use, blood flow to that region also
increases.
The primary form of fMRI uses the blood-oxygen-level
dependent (BOLD) contrast,[3] discovered by Seiji
Ogawa. This is a type of specialized brain and body
scan used to map neural activity in the brain or spinal
cord of humans or other animals by imaging the
change in blood flow (hemodynamic response)
related to energy use by brain cells.

59. MRI
SPECTROSCOPY
The basic principle that enables MR
spectroscopy (MRS) is the electron
cloud around an atom that shields the
nucleus from the magnetic field to a
greater or lesser degree. This naturally
results in slightly resonant frequencies,
which in turn return a slightly different
signal.

60. MR spectroscopy
MR spectroscopy (MRS)
Hunter's angle
lactate peak: resonates at 1.3 ppm
lipids peak: resonate at 1.3 ppm
alanine peak: resonates at 1.48 ppm
N-acetylaspartate (NAA) peak: resonates at 2.0
glutamine-glutamate peak: resonate at 2.2-2.4 ppm
gamma-aminobutyric acid (GABA) peak: resonate at
2.2-2.4 ppm
citrate peak: resonates at 2.6 ppm
creatine peak: resonates at 3.0 ppm
choline peak: resonates at 3.2 ppm
myo-inositol peak: resonates at 3.5 ppm

64.  Magnetic resonance elastography (MRE) is a non-
invasive medical imaging technique that measures
the mechanical properties (stiffness) of soft tissues by
introducing shear waves and imaging their
propagation using MRI. Pathological tissues are often
stiffer than the surrounding normal tissue. For instance,
malignant breast tumors are much harder than
healthy fibro-glandular tissue. This characteristic has
been used by physicians for screening and diagnosis
of many diseases, through palpation. MRE calculates
the mechanical parameter as elicited by palpation,
in a non-invasive and objective way.

66. SUSEPTIBILTY WEIGHTED IMAGES ( SWI) FOR HEMORRHAGE

67. THE END