Quiz 2 Flashcards
What is the optimal kv range for cervical spine?
75 - 85 kv
What is the optimal kv range for AP thoracic?
75 - 85 kv
What is the optimal kv range for lateral thoracic?
85 - 95 kv
What is the optimal kv range for AP lumbar?
80 - 90 kv
What is the optimal kv range for lateral lumbar?
85 - 95 kv
What is the optimal kv range for AP full spine?
80 - 100 kv
What is the optimal kv range for pelvis/hip?
75 - 85 kv
What does MAs of xray control?
the density
What % of MAs makes 1st visible/slight change in density?
30%
What is the result of 50% MAs?
reduce the density by 1/2
What is the 50% reciprocal rule?
doubling the MAs will double the density of the film
If the film is too dark but you can see the structures, how would you adjust the MAs to correct the film?
use the 50% rule: 1/2 the MAs
If the film is too light but you can see the structures, how would you adjust the MAs to correct the film?
double the MAs
An increase in kV by 15% will have what result on the film?
2x the density
A decrease in kV by 15% will have what result of the film?
Cut the density in half
If a film is too dark, but you can still see the images, what kV rule should you apply?
15% decrease in kV
If a film is too light, but you can still see the images, what kV rule should you apply?
15% increase in kV
What is another name for a High Contrast image?
a Short Scale image
How would you describe the appearance of a short scale image?
A black and white image with a few shades of gray in between
What is another name for a Low Contrast image?
a Long Scale image
How would you describe the appearance of a long scale image?
lots of grays
If a film is too gray, but the density is good; how would you fix the image?
Decrease the kV 15% AND double the MAs
If a film doesn’t have enough gray, but the density is good; how would you fix the image?
increase the kV 15% AND cut MAs in 1/2
If the film is too dark and the structures are NOT visible; how would you fix the image?
Decrease the kV by 15% AND cut the MAs in half
If the film is too light and the structures are NOT visible; how would you fix the image?
Increase the kV by 15% AND double the MAs
What is the scale used in the image on the left?
What is the scale used in the image on the right?
Left: long scale (to fix: decrease kV by 15% AND double MAs)
Right: short scale (good)
The top right imgae is ideal.
How do you get the top left image to look like the tip right?
Double the MAs OR increase the kV by 15%
The top right image is ideal.
How do you get the bottom left image to look like the top right?
Cut MAs in 1/2 AND decrease kV by 15%
The top right imgae is ideal.
How do you get the bottom right image to look like the top right?
decrease kV 15% AND double MAs
What is wrong with the image on the left?
What is wrong with the image on the right?
Image on the left is underexposed.
Image on the right is long scale.
What is wrong with the image on the left?
What is wrong with the image on the right?
Image on the left in overexposed
Image on the right is long scale
How would you describe the appearance of the left image?
How would you describe the appearance of the right image?
Left is short scale (ideal)
Right is long scale
What structure is seen in the image and why do we see it?
Earlobe
We see it because there is water and air causing a subject contrast
What is seen on the C5 vertebral body and why do we see it?
Luschka joint osteophyte is seen.
We see it because double bone density is superimposed
How would you fix this lateral lumbar?
Increase the kV by 15% AND double the MAs
What scale of contrast is this film?
Long Scale
How would you fix this film?
Decrease the kV 15% AND double the MAs
How would you make the film on the right look like the film on the left?
increase the kV 15% OR double the MAs
How would you fix this lateral lumbar?
Increase kV 15% OR double MAs
How would you make the image on the left look like the image on the right?
Decrease the kV 15% AND double the MAs
How would you correct this film?
Double the MAs OR increase kV 15%
There is only a slight change in these films. What is the rule we use if we retake this film?
30% rule
The film on the left has 30% more MAs than the film on the right
(slightly more dense)
OR
The film on the right has 30% less MAs than the film on the left (slightly less dense)
How would you adjust this film to see the lumbar spine or plevis?
Increase kV 15% AND double the MAs
How would you cirrect this film?
Decrease kV 15% OR cut the MAs in 1/2
What is the scale both films? How do we correct it, if necessary?
a) Short
b) long; decrease kV 15% AND double MAs
What is this structure (seen ant aspect of lower cervicals) and what 2 densities make it up?
Cornu of thyroid cartilage; made up of water and calcium
How do you correct the film on the left to look like the film on the right?
decrease the kV by 15% OR cut MAs in 1/2
How would you correct this film?
Increase the kV 15% OR double the MAs
If this image was taken at 80 kV, how would you correct the image?
Double the MAs if taken at 80 kV.
Optmial cervical kV is 75 - 85
What is the dark mass on the ilia and what naural densitie make it up?
Gas/Air; made up of air
How would you adjust this image to make it a good lateral lumbar?
decrease the kV 15% AND double the MAs
Side Note: Ideal kV for lateral lumbar is 85 - 95 kV
What is the large black mass in the pelvic cavity and why do we see it?
Fecal matter surrounded by gas/air
We see it because there is water density contrasted by air
How do we correct this film?
lower the film and either decrease the kv 15% OR cut MAs in 1/2
What are these structures and why do we see them?
Rib cartilages
we see them because they contain water and natural metal
What are the scales of these images and how do we fix them if necessary?
The film on the left is long scale; fix by decreaseing kV 15% AND doubling MAs
The film on the right is short scale
What is the light spot and why do we see it?
Axial view of a penis seen due to an increase in volume
What is the structure and why do we see it?
Ear cartilage
Seen because water density surrounded by air
How would you fix film a to look like film b?
There is distortion due to diverging rays in film a; fix by using a cephalic tilt to look like film b.
Why do we see the canal in C1?
Because of divergence
One of these films is taken AP and one is PA.
Which is which and how do you know?
The film on the left is P-A
The film on the right is A-P
Known by looking at the heart.
What is seen on the film and why do we see it?
Venous sinus is seen because of blood surrounded by calcium
What is the white ball seen in the image and why do we see it?
Fecal matter is seen because of increased volume
How would you correct this lateral cervical?
Decrease the kV 15% AND decrease MAs by 30%
