brief but informative knowledge about how CT works and what are its components ... easy to understand as well as presenting during lectures and in classes . share it

1. COMPONENTS OF CT
SCANNER
SIR SYED UNIVERSITY OF ENGINEERING AND
TECHNOLOGY
SYED HAMMAD
AKHTER
2012-BM-071
PRESENTED TO
ENGR. FAHAD
AKBER

2. COMPONENTS OF CT SCANNER
Gantry
Data acquisition
system
Operating
console
Gantry
Donut shaped part of CT scanner
Largest part of CT
Known as heart of CT
All circuits placed in it
Consist of
Xray tube Pre-patient collimeter Patient table Post patient collimeter
Detector

3. X-ray tube
Collimeter
Patient table
Consist of anode and cathode.
Compensating filters are used
to reduce the radiation dose to
patients and help to minimize
image artifacts
Pre and post are present
Reduce scattered radiations
that reaches to detector array.
Patient lies on the couch and
moved through Gantry aperture
during examination
Made of carbon fibres to
prevent it from interfering with
xrays

4. DETECTORS
There are two type of detector
•Scintillation detector
•Gas filled detector
SCINTILLATION
 PMT
 Photocathode
Material are used
 Sodium iodide
 Bismuth Germinate
 Cadmium tungstate
Converts x-rays to
signals
in term of light by the
process of Scintillation.
GAS FILLED
 Xenon
 Krypton
 Xenon + krypton

5. DATA ACQUISITON SYSTEM
Convert analog signals from the detector into digital signals
Detectors
Current to
voltage
converter
Pre
amplifier
computer
A/D
converter
Analog
Integrator
OPERATING CONSOLE
It consist of more than 1 consoles
For Radiologist
For Physician
For Data storage (film ,CD,hardware)

6. GENERATION MOVEMENT BEAM TYPE DETECTOR IMAGING TIME
First Translate-rotate Pencil beam
(single beam)
Single 5 min
Second Translate-rotate Fan beam 5-30 30s
Third Rotate-rotate Fan beam 5000-700/1000 1s
fourth Rotate-stationary Fan beam 4000 30ns
GENERATIONS OF CT SCANNER