VNO2 Manual X-rays Flashcards
What are the 5 stages of processing manual x-rays?
Development
Rinsing
Fixing
Washing
Drying
What is the main active ingredient in the developing solution?
Phenidone hydroquinone or metol-hydroquinone
What does the developer/active ingredient in the developer do?
The chemicals convert the expos d crystals of silver bromide into minute grains of black metallic silver.
How long should the film be immersed in the developer for?
3-5 minutes
What temperature should the developer stay at of the developer?
20 degrees
When should the developer be changed?
Usually every 3 months
How long should the x-ray film be rinsed for?
10 seconds
What is the purpose of rinsing the x-ray film?
Removes excess developer solution;and prevent carryover into the fixer tank
What is the fixer in a manual x-ray?
The fixer is acidic and this neutralises the developer preventing further development of the emulsion
What does the fixer contain?
Contains sodium or ammonium thiosulphate
What temperature should the fixer be at?
21 degrees Celsius
How long should the film remain in the fixer?
10 minutes
What is tanning?
3rd function of fixing, this hardens the film emulsion to prevent the film from being scratched when handled
What is washing of the x-ray film?
The film must be washed to remove residual chemicals which would cause fading and yellow brown staining of the film
How many litres of water should be used when washing the film?
3 litres
How long should the film be washed for?
15-30 minutes
What is drying of an x-ray film?
Films are removed from their hangers for drying. The films should be clipped to a taut line over a sink in a dust free environment.
What does an automatic processor consist of?
Light proof container enclosing a series of rollers that pass the film through developer, fixer, wash water and warm air.
What is the dry area?
The films are stored in boxes or in film hoppers. Dry film hangers should be stored o; a rack above the dry bench
What is the wet area?
This is where the processing chemicals are kept and used.
What can cause the film to be too dark?
Overexposure
Overdevelopment
FFD too short
Fogging
What can be done if the film is too dark?
Reduce exposure factors
Check developer temperature
Increase FFD
Check thickness of patient
What can cause the film to be too pale?
Under exposure
Underdevelopment
FFD too long
How can you tell if an x-ray is underexposed?
Background black but image is too light
If an x-ray is underexposed, how can this be fixed?
Increase exposure factors!check thickness of patient, check correct film/screen combination is used
Is the fixer alkaline or acidic?
Acidic
What is the main active ingredient in fixer?
Sodium thiosulphate or ammonium thiosulphate
Describe the reaction undergone during fixing?
The unexposed silver halide crystals are removed leaving a metallic silver image that may be viewed in normal light. Fixing renders the image permanent and insensitive to white light
What is the maximum wattage suitable for a safe light bulb?
25 watts
List 4 faults associated with poor handling of film during processing?
Finger prints
Emulsion damage
Static marks
Crimp marks
