8labgamma

BIOMEDICAL ENGINEERING SYSTEM

Gamma CameraEngr Khaleeque Ahmed

Sir syed university of engineering & technology

Karachi

GAMMA CAMERA

• A camera for nuclear imaging was invented by H. Anger in

the 1960’s (The Anger camera)

• Gamma camera is considered as one of the most

important devices used in the fields of nuclear medicine.

• Produce functional images of the body parts, used for

diagnosis purpose.

Anger camera

HOW A GAMMA CAMERA WORKS

Patient is injected by radiotracer(radioisotope), emits gamma radiation. Then gamma camera scans the radiation area and creates an image.

To detect the gamma photons we use a large crystal of sodium iodide. The crystal gives a tiny flash of visible light every time a gamma photon hits it. This flash is picked up by photomultipliers which convert the flash into an electrical signal. The electrical signals from the photomultipliers are analyzed by a computer to construct an image.

COMPONENTS OF GAMMA CAMERA

Collimator

Detector

PMT(photomultiplier tool)

Position localization circuit

Correction circuitry

Monitor

COLLIMATOR

Made up of large number of small holes drilled in a

plate of lead.

Provide right direction

Types

-parallel hole

-pin hole

-converging

-diverging

DETECTORS

Converts received radiations into light photons

Used scintillation detectors (NaI)

PMT(PHOTOMULTIPLIER TOOL)

Its an evacuated glass tube

Perform two functions

1st conversion of light photons

2nd signal amplification

POSITION LOCALIZATION CIRCUIT

Provide positional information

COMPUTER

Process incoming data

Display it as a readable image

Store images

THANK YOU………….!!!!