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Dr. Hussein A. Hassan

Photoflurography new microsoft office powerpoint 97 2003 presentation

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Page 1: Photoflurography new microsoft office powerpoint 97 2003 presentation

Dr. Hussein A. Hassan

Page 2: Photoflurography new microsoft office powerpoint 97 2003 presentation

Photofluorography((Fluorography

Taking a photograph (whether it be a dynamic cine run or a series of static pictures) of those images produced at the output phosphor of an image intensifier.

Page 3: Photoflurography new microsoft office powerpoint 97 2003 presentation

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

CameraFilm size

Cine camera16-mm or 35-mm

Serial -camera70-mm or 105-mm roll film100-mm sheet film.

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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.

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Page 8: Photoflurography new microsoft office powerpoint 97 2003 presentation

Film Screen Radiography (Spot Film Device )

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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.

Page 10: Photoflurography new microsoft office powerpoint 97 2003 presentation

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.

Page 11: Photoflurography new microsoft office powerpoint 97 2003 presentation
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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.

Page 13: Photoflurography new microsoft office powerpoint 97 2003 presentation

Cine cameraThe 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.

Page 14: Photoflurography new microsoft office powerpoint 97 2003 presentation

When a cine camera is used to record images from the image intensifier, the process is commonly known as cinefluorography.

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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.

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Processing fluorographic filmA special processor for processing all types of

roll film, 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.

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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

Page 18: Photoflurography new microsoft office powerpoint 97 2003 presentation
Page 19: Photoflurography new microsoft office powerpoint 97 2003 presentation

Presentation of fluorographic filmFluorographic 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.

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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.

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Advantages of VTR over cineradiography1. Immediate playback.2. No processing required.3. No special projection equipment needed.4. The reusable.5. Contrast and brightness are adjustable on

the TV monitor during playback.6. Sophisticated search and replay facilities.7. Reduce radiation dose.

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Disadvantages of VTR 1. Image resolution is inferior.2. The quality is still frame viewing.3. Tape /head were may become a problem.

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Laser imagerThe 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.

Page 30: Photoflurography new microsoft office powerpoint 97 2003 presentation

Imager constructionThe 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.

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The laser imager in useThe 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).

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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

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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.

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Advantages of using a laser imager1. Very high resolution

images.2. Improve grey scale level.3. Less image distortion.4. Choice of formats;

1,2,4.6,9,15 or 20 images on film.

5. Images may placed in any preferred position on the film

6. Choice of positive or negative image.

7. Choice of clear or black border on the film.

8. The imager can be interfaced with several imaging modalities.

9. The unit can controlled remotely.

10. Any number of identical copies may be made rapidly.

11. The imager is self-monitoring so that equipment fault may identified and corrected quickly.

12. No cassettes to insert every time a film is required.

13. The imager may linked directly to automatic processor.

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Page 38: Photoflurography new microsoft office powerpoint 97 2003 presentation

CRT cameraCRT 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.

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Video imagers or multi formatters

Video imagers or multi formatters enable several image to be recorded on a single sheet of film.

Page 41: Photoflurography new microsoft office powerpoint 97 2003 presentation

Designs features Automated self-contained video imager

consist of a number of essential features;1.Cathode ray tube2.Optical system3.Film platform4.Control system and electronic5.Multiformat option.

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Page 43: Photoflurography new microsoft office powerpoint 97 2003 presentation

Benefits of using a multiormat video imager

1. Greater choice of image format;2. Automatic exposures control;3. CRT- setting memory;4. Automatic image advance;5. Double exposure prevention;6. Ease of use;

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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.

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Advantages ;No wet chemical processing is required.Laser imagers are therefore able to produce

high quality film images without the associated automatic processor.