Flashcards in Bushong reading Ch 11 Deck (15):
Contrast arises from what areas?
Light, dark and shades of gray on the x-ray image
What are the two principal characteristics of any image?
Spatial resolution and contrast resolution
Image contrast and reduces patient dose
What does reduced image contrast result from?
Grids with high frequency show...
Less distinct lines on images
What is the single largest factor in poor image quality?
What is the principal function of a grid?
To improve image contrast
What is the simplest type of grid?
What is grid cutoff?
The undesired absorption of primary x-rays by the grid
What is the main disadvantage of parallel and crossed grids?
What type of grid is fabricated so that grid strips are parallel to the primary x-ray path across the entire image receptor?
High ratio grids have less positioning __________ than low ratio grids
What will happen if a grid is installed incorrectly and moves in the same direction as the grid strips?
Grid lines will appear
Greater positioning latitude is possible with what type of ratio grids?
Low ratio grids