Grid Test
1) A Grid is used to improve contrast by _______.
2) Scatter increases and Contrast is impaired as KVP ________.
3) T or F -Scatter decreases with increasing volume of tissue being radiated AND decreases with increased atomic number of the tissue.
4) T of F – A 12:1 grid ratio will absorb more scatter than an 8:1.
5) ________ Grids are more commonly used because they allow for tube angulations.
6) T of F – A focused grid with lower grid ratios has a greater latitude than higher grid ratios
7) A focused grid has a point where all of the lead strips would intersect if they were extended this line is called ______ _______.
8) When the grids leads strips are absorbing the primary beam as a result of bad tube angulations you get ______ ______.
9) T or F – Parallel grids work better at short distances than long distances.
10) Grids that absorb a greater percentage of scatter than primary radiation are said to have a greater ________
11) K-Factor is a formula used to measure the contrast improving ability of a grid, the higher the K-factor the ________ the contrast improvement.
12) T or F – A parallel grid will be as effective if you accidently used it upside down.
13) The _____ ______ is another method of reducing scatter if a grid is unable to be used
Answers
1) Absorbing Scatter
2) Increases
3) First part False it increases, second part True
4) True
5) Linear
6) True
7) Convergence Line
8) Grid Cutoff
9) False, Because of the divergence of the beam, its best at long SID
10) Selectivity
11) Better
12) True
13)Air-gap Technique
