Lecture 6 Flashcards
What is the degree of blackness on a radiograph dependent on
The amount of x-rays reaching the film
If there’s no patient between the film and the x-ray beam what color will the film be
Black
What is the emulsion layer of the film
Contains silver hollered crystals suspended and disbursed evenly throughout the layer. On both sides to increase film sensitivity, speed, density, contrast
When the film is developed in developer solution the sensitized silver will be converted to what on the x-ray film after processing
Dark black dots
If there is an object between the x-ray beam and the film, exposing the film to radiation will create a what image because not all x-rays will reach the film
Latent
After producing the film the latent image will be converted to what
2-D image
What is MA used for
To control the quality of x-rays produced by the x-ray beam. When MA is increased a higher number of x-rays are generated
What is the length of exposure time
The period of time during which the x-rays are permitted to leave the x-ray tube.
What is the general exposure time for dogs at Vanier
1/24
What is the general exposure time for cats at vanier
1/30
What does the MAS describes
The total quantity of x-rays produced by the x-ray tube at a given time.
What is the KV P
Amount of electrical energy being applied to the anode and cathode to accelerate the radiation from the cathode toward the target
What happens when KV P is increased
The penetrating power of x-ray through tissue is increased
What are the three things that radiographic quality is dependent on
Radiographic density, radiographic contrast, radiographic detail
What is radiographic density
The degree of blackness on a radiograph.
What can the radiographic density be increased by
Increasing the MAS, increasing the KV P
What is radiographic density also influenced by
Thickness and type of tissue
Tissues. That have higher density absorb more x-rays and result in what color
White or light image
What can you say about bones and x-rays in terms of density and contrast
They have a high density. But decrease the radiographic density. They are high contrast
What is radiographic contrast
The difference in density between two adjacent areas on a radiographic image
What is low contrast
Long scale of contrast. Many shades of gray
What is a high contrast
Short scale of contrast. Few shades of gray. Ex: bones
What is radiographic contrast affected by
Subject density, KV P level, scatter radiation, film fogging
What is the definition of subject density in relation with radiographic contrast
The ability of the different tissue density us to absorb x-rays. Xers penetrate the various tissues depending on differences in atomic number and thickness
