8labgamma
TRANSCRIPT
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………….!!!!