3. Image Recording in non Digital Fluoroscopy
For analogue image intensifier system, image recording
was done by;
1. Film-screen Radiography.(not fluorography)
2. Serial camera or cine camera (Photofluorography)
Camera options
Camera
Film size
Cine camera
16-mm or 35-mm
Serial -camera
70-mm or 105-mm roll film
100-mm sheet film.
4.
5.
6. Film Screen Radiography (Spot Film Device )
The equipment incorporated a cassette holder that
could be introduced between the grid and image
intensifier.
During fluoroscopy, the holder, with film cassette in
place, was parked out side radiation beam.
On pressing the radiographic exposure switch, the
cassette with film in place automatically driven into
position and the exposure made innless than 1 sec.
These films were commonly referred to as spot films.
9. (Serial Camera (Spot Camera
An alternative method of taking spot films was to
use a camera attached to image intensifier, which
using mirror introduced between the output
phosphor and TV camera,
A separate lens system could take a picture of the
image on the output screen of intensifier.
The size of film is 100 or 105 mm, These films
were sometimes referred to as photospot images,
and the term fluorography was induced to
describe recorded images produced by
fluoroscopy equipment.
10. (Serial Cameras (Spot-Film / rapid sequence
All of them record the image intensifier output
phosphor picture via the image distribution box as in
cine camera.
Control by switching of x-ray generator. No x-rays, no
image.
Capable of recording images at rate of 1 per second
(single shot) or rapid sequence of up to 12 image per
second.
11.
12. Camera features
Separate supply and take –up magazine.
Automatic exposure of patient data on film.
Automatic recording of serial number of each shot in
a sequence.
A safety mechanism to prevent use if camera runs
empty or patient’s identity is not inserted.
13. Cine camera
The static camera could be replaced by a cine camera.
These cameras take a rapid series of pictures or
frames on 16mm or 35 mm roll film.
When the film is processed and played back through
a projector at similar rate, the eye perceives moving
image.
Such systems were standard in cardiac studies prior
to introduction of digital systems and Ba swallow.
The film exposed at rates usually in excess of 16
frames per second.
14. When a cine camera is used to record images from the image intensifier, the process is
commonly known as cinefluorography.
15. Shutter;
•This is the mechanism in camera which control the duration
of exposure.
•In cine camera it takes the form of a shaped disc of metal
which continuously rotates between the lens and the
aperture when camera filming.
16. Processing fluorographic of roll film,
film
A special processor for processing all types
Such a processor wil also take 100-mm sheet film if
special adaptor is first attached.
The roll film can be processed satisfactorily in standard
automatic processor, providing that a leader is attached.
17. The Scopix 12 roll film processor. The processor is capable of processing all roll
films from 35 mm to 105 mm and with special feeder will also process 100x 100
mm film sheet
18.
19. Presentation of fluorographic film
Fluorographic films are more difficult handle
during the viewing and reporting stage. Here are
two methods for ease handling of them;
1. Film viewing mounts; these are transparent film
packets designed to hold 4 to 6 100 mmx100 mm
film and are made from rigid, clear PVC.
2. Lamination ; this a procedure whereby the films
are mounted between two clear sheets of plastic
film, which are then bonded together is high
temperature and pressure provided by a specially
heated rollers.
20.
21.
22. Recording the television image
Methods of image recording which take place at point
after TV pick-up camera has been involved in the
image process.:
The imaging methods available are:
1. Video tape recorder (VTR).
2. Laser imager.
3. CRT camera (polaroid or multi-imager.
4. Video imager or multiformatter.
5. Dry silver imager.
23.
24.
25.
26.
27. Advantages of VTR over cineradiography
1.
2.
3.
4.
5.
6.
7.
Immediate playback.
No processing required.
No special projection equipment needed.
The reusable.
Contrast and brightness are adjustable on the TV
monitor during playback.
Sophisticated search and replay facilities.
Reduce radiation dose.
28. Disadvantages of VTR
Image resolution is inferior.
2. The quality is still frame viewing.
3. Tape /head were may become a problem.
1.
29. Laser imager
The laser imager provides a hard-copy image by
using the infrared beam from a laser to exposure the
film.
The image may connected to several imaging
modalities, such CT, MRI, digital fluoroscopy and CR.
30. Imager construction
The imager comprises a film-supply magazine, an
exposure section and a film take up magazine.
Instead of take magazine the imager may connected
via docking unit to an automatic processor.
A source of laser beam e.g. in the 3M imager is a solid
state diode emitting an infrared beam with a
wavelength of 850 nm.
A sophisticated optical system, comprising lenses
and polygonal mirror to focus and move the laser
beam a cross the film during the scan sequence.
A control panel to enable range of operation
functions.
31.
32.
33. The laser imager in use
The chosen images for imaging are relayed in form of
video signal to an analogue –to- digital converter within
the imager.
Digitized images may stored in the imager’s internal
memory.
Pressing the print ‘button’ on the key pad, will initiates
the following sequence of events.
A film is conveyed to the scanning area. It scan by laser in
a direction at right angles to the line of film travel.
The intensity of laser beam varies (modulates) in
proportion to the intensity of signal being received by
memory store( creation of various densities on the film).
The whole sequence-from supply to take- up magazine
takes only 23 s (the printing cycle takes only 8.5 s).
34. The Film
The film used is single-sided, with an infrared sensitive emulsion to match the
850 nm laser emission. Can be processed using the same chemistry as for x.ray film.
Should be handle either in complete darkness or greens filter over the safelight
35. ?Why a laser
There are 3 principal advantages of using a laser beam
rather than a conventional light spot to put the image
on the film:
1. The laser has one wave length;
2. The light beam is parallel and not divergent;
3. The of high intensity.
these features means result in an image of very high
resolution.
36. Advantages of using a laser imager
1.
2.
3.
4.
5.
6.
7.
8.
Very high resolution images.
Improve grey scale level.
Less image distortion.
Choice of formats; 1,2,4.6,9,15
or 20 images on film.
Images may placed in any
preferred position on the film
Choice of positive or negative
image.
Choice of clear or black border
on the film.
The imager can be interfaced
with several imaging
modalities.
9.
10.
11.
12.
13.
The unit can controlled
remotely.
Any number of identical
copies may be made rapidly.
The imager is self-monitoring
so that equipment fault may
identified and corrected
quickly.
No cassettes to insert every
time a film is required.
The imager may linked
directly to automatic
processor.
37.
38. CRT camera
CRT camera basically consist of a single lens
connected via a custom-deigned mount to CRT
screen.
The film holder employed at rear of the camera use
8x10 inches cassette is mounted inside the frame
which can moved up or down and side to side to
obtain up to six images.
There is aperture and shutter control facility.
The camera lens is of fixed focal length. The camera
initially set up the lens is focused on the ground
screen positioned in placed of the CRT. Once this has
been done, the glass screen is removed and the
camera is ready for use.
39.
40. Video imagers or multi formatters
Video imagers or multi formatters enable several image to be recorded on a
single sheet of film.
41. Designs features
Automated self-contained video imager consist of a
number of essential features;
1. Cathode ray tube
2. Optical system
3. Film platform
4. Control system and electronic
5. Multiformat option.
42.
43. Benefits of using a multiormat video imager
1.
2.
3.
4.
5.
6.
Greater choice of image format;
Automatic exposures control;
CRT- setting memory;
Automatic image advance;
Double exposure prevention;
Ease of use;
44.
45. Dry silver imager
A dry silver imaging film with transparent polyester
base is used with laser imager (phototherography).
A specialized light-sensitive material emulsion
containing a silver halide is coated onto a base of
polyester.
The top coat fulfills two functions ; to prevent
halation and to protect sensitive emulsion.
When light from a CRT image display or laser
exposes the emulsion a latent imager is created.
Visible image is made by using heat as reducing
agent.
46.
47.
48.
49.
50. ; Advantages
No wet chemical processing is required.
Laser imagers are therefore able to produce high
quality film images without the associated automatic
processor.
