Anatomically Programmed Radiography and Techniques

Question 1

What is the purpose of APR? What factors does it show you on the monitor?

Answer 1

-Purpose is to standardize everything (Is a default) to get the same results
-Focal spot size, kVp, mAs, mA, AEC, bucky, filtration, SID, grid/no grid, sec. comes up when we select a procedure

Question 2

Can we change APR?

Answer 2

Yes, they come preset by a certain vendor with certain techniques-however we can change them

Question 3

What factors are standardized with an APR in AEC?

Answer 3

1. kVp,
2. back up time,
3. detector,
4. density selectors

Question 4

What sometimes happens to back up time when you increase density selectors?

Answer 4

Back up time increases

Question 5

When using AEC, what 3 factors do we need to be aware of after we take our exposure? Why?

Answer 5

1. Be aware of the anticipated mAs for the exposure
2. Know your final technique
3. Appropriate EI ranges for each exposure
   -Why: Because we are responsible for the total amount of radiation the patient receives

Question 6

Why do we need single variable technique charts?

Answer 6

-Standardization and consistency of techniques and procedures

Question 7

What does having translucency between overlying structures mean/

Answer 7

The ability to see structures through structures. i.e.; seeing patella over knee

Question 8

What is the main determining factor for contrast?

Answer 8

Algorithm (we don’t adjust this)

Question 9

How can we prove that the algorithm exists?

Answer 9

Can prove that different algorithms exist by taking exposures using different APR’s with the same body part

Question 10

What are the 2 benefits of single variable technique charts?

Answer 10

a. Best standardization
b. Least errors

Question 11

What is the one factor that is not standardized in fixed technqiues with a single variable chart?

Answer 11

Time/mAs

Question 12

Define optimum kVp

Answer 12

It is a certian kVp picked that is able to penetrate a range of different thickness (body size) to provide optimum contrast (can penetrate small, med. large)

Question 13

What 3 factors should we know when we select an mA?

Answer 13

1. Fss
2. Approximate exposure time
3. Heat on the anode

Question 14

What is the variable on our single variable technique charts? What other factor does this change as the body part size changes?

Answer 14

-Time is typically our variable
-As patient/part size changes:
○ time changes
○ mAs changes

Question 15

What are the requirements for single variable technique charts in order to get consistant results?

Answer 15

1. QC Program
2. Constant input
3. No one changes the tech chart unless everyone agrees
4. Periodic evaluation
5. Everyone must follow them

Question 16

What principle does using a technqiue by proportionality follow?

Answer 16

Principle of equivalent total technique

Question 17

What does Equivalent total technique mean?

Answer 17

The total amount of radiation for an exposure and gives us something to work off of to figure out other techniques

Question 18

What positions have the same total technique (using mA and s with reciprocity)

Answer 18

1. AP Lsp
2. AP ABD
3. AP Pelvis
4. Townes skull

Question 19

With an oblique torso, what total mAs would you use if you were given the mAs for an AP torso?

Answer 19

2x the amount for AP

Question 20

With an Lateral torso, what total mAs would you use if you were given the mAs for an AP torso?

Answer 20

4x the amount for AP

Question 21

What projections have the same SID, and therefore the same techniques?

Answer 21

1. All c-sp (13cm)
2. AP shoulder
3. Lat skull
4. AP/PA Knee

Question 22

What is the four cm rule?

Answer 22

-For every 4cm of thickness change, Double mAs (approximately)
-Only applies to the same body parts with different projections

Question 23

What is the rule for using an optimum kVp?

Answer 23

kVp should never < optimum for the body part (will always be a little bit higher to penetrate thickness)

Question 24

What are five factors to keep in mind when using techniques by proportionality?

Answer 24

1. Bucky factors
2. Inverse sq law
3. Generators
4. 4cm rule of thumb
5. 15% rule

Question 25

As we go from single phase to high frequency, what happens to mAs, # of photons, peak E, and average E?

Answer 25

mAs-can decrease
Number of photons-Increases
Peak E-no change
Average energy-increases

Question 26

What kVp do you use for the shoulder? What detector do you use?

Answer 26

75-85 and center

Question 27

What kVp do you use for the ankle?

Answer 27

60-75

Question 28

What kVp do you use for a knee? what detectors?

Answer 28

70-85
Center

Question 29

What kVp do you use for an Abdomen SC? What detector?

Answer 29

100-125 and all 3 detectors

Question 30

What kVp do you use for an Abdomen DC? What detectors?

Answer 30

80-90, all 3

Question 31

What kVp do you use for a hip/pelvis? What detector?

Answer 31

80-85
Center