LECTURE 7 PROCESSING AREA and VIEWING SECTION KAAB mid-uitm
LESSON OBJECTIVES
At the end of the session, student should able to:-
• Explain the viewing boxes, processors, darkroom and its components.
• Compare between different types of processors.
• Describe the darkroom design and its function.
• Explain the importance of the design towards radiography field.
LET’S REVIEW
• NAME SOME COMPONENTS OF THE STRUCTURE OF THE FILM
• WHAT IS THE PURPOSE OF THE BASE AND EMULSION?
• WHAT IS THE IMAGE CALLED BEFORE IT IS PROCESSED?
• WHAT IS THE SENSITIVITY SPECK?
Viewing Area
Viewing Boxes
• to suit every professional need.
• viewing systems have been developed specifically for different applications.
• offer levels of quality and performance superior to ordinary light boxes, and provide the bright, uniform, glare-free illumination that enable details of potentially crucial diagnostic significance to be examined in comfort.
Viewing Area
• Wide choice of sizes for wall mounting or free standing use.
• Uniform illumination for accurate examination of radiographs of all sizes.
2) Processing Area
Automatic Film ProcessorDaylight Film Processor
Film IdentificationFilm BinSafelight
Darkroom Design
Automatic Film Processor
• Processing Films in 4 stages:-
Developing
Fixing
Washing
Drying
Note: We had discussed this topic earlier.
Major functions:-- load cassette of unexposed film- ID printing- unload cassette- process films, incorporated with automatic
film processor.
2 types:i) Composite typeii) Modular type.
Daylight Film Processor
Daylight Film Processor
All components (film supply magazines, film dispensers, unloading machinery, and processor) in one unit.
i) Composite
Daylight Film Processor
ii) Modular
Cassette-loading equipment @ film dispenser away from automatic processor.
Special cassette with spring-flap where film is loaded and unloaded.
Film unloader with patient ID printer, then transport to auto-processor.
Daylight Film Processor
Composite
Advantages
• the result of one single action
• cassette can be handled manually
• small processing area
Disadvantages
• processor cannot be used separately
• heavy workload
Modular
• More versatile, can be located separately
• Darkroom facilities can be retained
• No congestion for staff to reload cassettes
Film Identification
• Pt name• Exam date & time• Pt x-ray number• Pt Birthday/DOB• Rt or Lt marker• Optional
– Exam type–Dr. Name
Film Identification
Patient particulars are being placed on top.
Cassette is “flashed” with name – can be done before or after image is taken.
Must be done BEFORE
PROCESSING
FILM.
RADIOGRAPHIC FILM SIZES
• 14 X17 inches
• 14 x 14
• 12 x 15
• 10 x 12
• 8 x 10
• 35 x 43 cm
• 35 x 35
• 30 x 40
• 24 x 30
• 18 x 24
Safelight
• Film is designed to be insensitive to specific wavelengths of orange-red light.
• The amount of light is controlled by:-
a) The type of filter
b) Wattage of the light source
c) Distance from the film tray
• Not all films insensitive to safelight, some require total darkness.
Safelight
A safelight has three basic parts:
• The lamp housing. This holds the bulb and the filter, and keeps the white light emitted by the bulb from escaping.
• The safelight filter. This absorbs light of some colors and transmits light of others to varying degrees.
• The bulb. The recommended wattage is determined by the sensitivity of a particular material, the transmission characteristics of the filter, the type of illumination the lamp housing provides -- spot (direct) vs general (indirect) -- and the distance between the safelight and the area where you handle the material.
Safelight
• RED — GREEN LIGHT SENSITIVE FILM ORTHOCHROMATIC
• AMBER – BLUE LIGHT SENSITIVE FILM
• TOTAL DARKNESS FOR PANCHROMATIC FILM
Safelight
• Example for Kodak Brand:-
Filter Color For use with Direct Indirect
2 Dark Red Fast orthochromatic materials. Some green-sensitive x-ray films.
15-watt 25-watt
6B Brown/ Amber
Other blue-sensitive x-ray films. 15-watt 25-watt
Darkroom – Still Necessary?
• Darkrooms are necessary for manually fed processors and daylight processors.
-Loading automatic film processor magazines.
• Necessary for conducting certain quality control tests (daily sensitometric strip).
Darkroom Design
Location
Location – center, hatch, away from damp / hot, power & water supply, near with viewing area.
Shielding
• Adjacent to x-ray room – must be lead shielded.
• At least 1/16inches of thickness surrounding the darkroom
Darkroom Design
Ventilation
• System must be lightproof and able to filter out dust.
Humidity
• relative humidity 40-60%
• > 60% - FILM FOG
• <40% - STATIC ARTIFACTS
Darkroom Design
Size
• BIG ENOUGH!!!?
• minimum 10m² floor, 2.5-3m ceiling.
Colour
• light-color, reflect safelight to assist operator, easy to wipe and clean (tiles).
Darkroom Design
Temperature
• temperature 18-20°C/ 50-70 ºF
• Suitable for film storage as to slow down the aging process of film.
Floor
• durable, easy to maintain, non-porous, non-slipped, light-color (put tiles).