REAL-LIFE USE OF ‘ANTIMATTER’ AND ‘MATTER’.

BY: K. SRUJAN REDDY.

X-rays Very little ordinary

light can pass through skin. It’s either absorbedabsorbed at the surface or reflectedreflected back…..

To “see” inside we need a kind of “light” with more more energyenergy…

SkinOrdinary Light

X rays

Taking “X rays”

The patient is placed in front

of a source of X RAYS

X ray Tube

A photo graphic plate is

placed on the other

side of the patient

Most of the X rays

pass through

the patient’s body…….

X-rays are absorbed by bone but can pass through skin and soft tissue

bone

Soft tissue

Photographicplate

X rays that are absorbed in the photographic plate cause chemical changes. These show as darkened areas when the plate is developed.

X-rays are also partly absorbed by some tissues in the body this creates a more subtle picture.

bone

Soft tissue

Photographicplate

What part of the body do these X Rays show?What part of the body do these X Rays show?

Answer:

A knee bone.

WHAT DOES THE ARROW INDICATES?

ANSWER: GROWTH PLATES.

CT ScansCTCT or “CAT” scans take X ray imaging to

“CC” stands for “Computed”

“TT” stands for “ Tomography”

In short….CT scanners are complex X ray machinesattached to very clever computersusing complicated mathematics to build up images of our insides.

The patient is placed on a bedThe scanner (X ray machine) is the shape of a ring

The patient is slowly moved through the The patient is slowly moved through the ring as the scan takes place…ring as the scan takes place…

Looking end on….

X ray tube

X ray detector

Patient

X Rays are produced in an X ray tube, pass through the patient and are detected by the detector

The scanner rotates the X ray tube and detector so the patient is scanned from all angles

MRI What do the letters stand for?

MM……….. Magnetic

RR………… Resonance

II…………. Imaging

MRI scanners MRI scanners do notdo not use use X raysX rays..

MRI Explained...

Your science studies have shown you that your body is made up of living cellscells…

Which are made up of moleculesmolecules …

Which are made up of atomsatoms

electron

neutron

proton

The simplest atom is…

Hydrogen1 electron

1 proton

It’s nucleus contains just one proton

After many years of investigation physicists found they could affect the tiny nuclear magnets of hydrogen atoms using very strong magnets and radio waves…

Bring in the magnets….Bring in the magnets….

S NNote: The nuclear magnets can line up in two possible directions A pulse of radio waves can cause some of the

nuclear magnets absorb energy and “flip”

This high energy situation cannot be sustained for long. Many will “flip” back….When this happens energy is released as a tiny

pulse of radio waves !!!

… ….watch how the magnetic field affects the tiny nuclear magnets.watch how the magnetic field affects the tiny nuclear magnets

The patient is placed on a bed and then moved into a large hollow tube.

The tube contains a very powerful The tube contains a very powerful magnetmagnet….….

Using an MRI Scanner…

Patients may be asked the following questions: Have you ever worked in the army or

metal working industry?Metal fragments (especially in the eye) could become Metal fragments (especially in the eye) could become dislodgeddislodged

Do you have a pacemaker?If yes you cannot have an MRI scanIf yes you cannot have an MRI scan

Do you have any dental implantsSome could become magnetisedSome could become magnetised

Do you have any metal pins or staples in your body?Some could become magnetised and need to be checked that Some could become magnetised and need to be checked that they will hold in place during the scanthey will hold in place during the scan

With the patient safety check complete the scan can begin…The part of the body

to be scanned is placed in the centre of the primary primary magnetmagnet

XThe magnet field produced has to be very steady and strong

This field causes the Hydrogen nuclei in the patients body to line up with the field

X

Three further coils are embedded into the tube….GRADIENT MAGNETS… these are used to fine tune the magnetic field so particular body parts and tissue types can be focused on.The patient will know when these magnets are switched on…they can make a loud banging noise.More coils provide a pulse of radio waves that cause some of the “nuclear magnets” to flip….The machine waits and records any radio signals that are then emitted by the patients body…..

What is PET?

PET is a noninvasive, diagnostic imaging technique for measuring the metabolic activity of cells in the human body.

It was developed in the mid 1970s and it was the first scanning method to give functional information about the brain.

Introductions to PET(positron emission tomography)

““snapshot”snapshot” images are useful

but doctors sometimes need “real time”“real time” pictures of how parts of your body are functioning…

e.g. How your heart is e.g. How your heart is

functioning.functioning.

Moving images can be achieved with MRI but PET scanning can give excellent results…

What are some of the uses for PET. Patients with conditions affecting the brain. Heart. Certain types of Cancer. Alzheimer’s disease. Some neurological disorders.

PET SCANNERS LOOK LIKE CT SCANNERS…

The key differences:The key differences:

-NO X RAY TUBE.

-The ring is surrounded by “Gamma RayGamma Ray” detectors

What are “gamma rays” and “positrons” ?

A little detour….

You will have heard of…Electrons

Protons

Neutrons

These are the building blocks of atoms.These are the building blocks of atoms.

Physicists have discovered a whole host of Physicists have discovered a whole host of otherother particles particles that exist !!!that exist !!!

AND ASWELL:AND ASWELL: Every particle has it’s own Every particle has it’s own ANTI ANTI PARTICLEPARTICLE……

Its….Its….

equivalentequivalent

The antiparticle of the electron is called a…

When an electron and a positron meet they annihilate…

The energy released creates 2 gamma rays

Looking at the scanner: end on….

Ring of gamma ray detectors

Patient

The radio tracer produces positrons which annihilate with electrons in the patients body producing pairs of gamma rays.

The energy and position of all the gamma rays are recorded and turned into an image by a computer.

The radiotracer concentrates itself in certain tissue types…

This glucose type radiotracer has concentrated itself in high glucose using cells like the brain, kidneys and cancer cells.

PET Scans are very expensive…

The biggest cost is in the production of the RADIOTRACERS.

The hospital needs to have access to a “CYCLOTRONCYCLOTRON” to create them

(several million euro to buy one!)

Radiotracers have to be used straight after they are produced….they cannot be stored.

POINTS TO BE NOTED.

Not all cancers have positive PET Scans Not all positive PET scans are cancers

Brief Introduction to MEG(magnetoencephalography)

MEG is different to all the other techniques…MEG is different to all the other techniques…

It doesn’t put anything into a patients body….No X rays/Strong Magnetic Fields/Radio

waves/Radiotracers.

It just measures something It just measures something that is already there…that is already there…

Your body is full of tiny electric currents!

These tiny currents produce tiny magnetic fieldsThese tiny currents produce tiny magnetic fieldsMEG is able to measure some of these.MEG is able to measure some of these.

MEG is mostly used to image brain activitybrain activity.

MEG scanners measure measure tiny magnetic fieldstiny magnetic fields produced by electrical brain activity.

These fields are so weak (10,000 million10,000 million times weaker that the earths magnetic field) that the scanner needs to be in a specially shielded room.

THANK YOU FOR YOUR VALUABLE TIME.