UNIT 1 REVIEW ASSIGNMENT AND EXAM Flashcards
An image with significant penumbra can be described as having:
A. A grainy appearance
B. Good spatial resolution
C. Poor spatial resolution
D. Low contrast
C. Poor spatial resolution
Which of the following images would have the best spatial resolution?
A. 80 kVp, 25 mAs, 72” SID, 0” OID, 1.0 mm FS
B. 75 kVp, 16 mAs, 48” SID, 4” OID, 1.5 mm FS
C. 90 kvp, 32 mAs, 68” SID, 1” OID, 1.0 mm FS
D. 80 kVp, 32 mAS, 72” SID, 2” OID, 2.5 mm FS
A. 80 kVp, 25 mAs, 72” SID, 0” OID, 1.0 mm FS
Quantum mottle can be improved by repeating the image with:
Less mAs
A grid
More mAs
More SID
More mAs
Which of the following factors impact size distortion? (select all that apply)
FSS
SID
Grid use
Filtration
OID
OID, SID
Which of the following line pairs would describe an image with the worst spatial resolution?
A. 12 lp/mm
B. 10 lp/mm
C. 15 lp/mm
D. 5 lp/mm
D. 5 lp/mm
Which of the following SID’s would result in the least amount of magnification?
A. 60”
B. 56”
C. 72”
D. 40”
C. 72”
Which of the following would cause an increase in total IR exposure?
A. Increase in kVp
B. Decrease in mAs
C. Increase grid ratio without mAs compensation
D. Increase SID
A. Increase in kVp
All of the following are acceptable solutions in order to decrease motion artifact. (select all that apply)
- Using a grid.
- Proper communication with the patient.
- Immobilization of the part.
- Use the shortest possible exposure time.
- Use a long exposure time.
- Proper communication with the patient
- Immobilization of the part
- Use the shortest possible exposure time
Which of the following images would have the lowest subject contrast?
A. 100 kVp, 20 mAs, 40” SID, 0” OID, wide open collimation, no grid
B. 80 kVp, 25 mAs, 48” SID, 0” OID, 4 X 4” collimation, 16:1 Grid
C. 100 kVp, 32 mAs, 56” SID, 1” OID, 8 X 10” collimation, 5:1 Grid
D. 90 kVp, 16 mAs, 40” SID, 2” OID, wide open collimation, 8:1 Grid
A. 100 kVp, 20 mAs, 40” SID, 0” OID, wide open collimation, no grid
Which of the following factors have an impact on total IR exposure? (select all that apply)
- FSS
- Grid use
- mAs
- kVp
- OID
- SID
- Grid use
- mAs
- kVp
- OID
- SID
A radiograph is taken and the resulting image is extremely grainy and it is difficult to discern any detail in the anatomy. What is likely the problem and what step(s) could the technologist take to try to fix it?
A. The radiograph is underexposed. The technologist should double the mAs and reshoot the x-ray.
B. The radiograph is overexposed. The technologist should decrease the mAs and kVp and reshoot the x-ray.
C. There is excessive scatter on this image. The radiographer should reshoot the image using a high ratio grid and adjust the mAs accordingly.
D. The radiographer should adjust the window level to a more appropriate brightness and send the image to PACS
A. The radiograph is underexposed. The technologist should double the mAs and reshoot the x-ray
Quantum mottle is caused by
A. Saturation of the IR
B. The kVp is too high
C. Too much scatter reaching the IR
D. Inconsistent or uneven distribution of x-ray photons on the surface of the IR
D. Inconsistent or uneven distribution of x-ray photons on the surface of the IR
A gall stone measures 2.7 cm on a radiograph. Once it is removed, the stone actually measured 1.2 cm. What was the magnification factor of the gall stone in the image?
A. 3.0
B. 1.5
C. 2.25
D. 1.8
C. 2.25
*use the magnification factor formula
A radiograph of the knee demonstrates an avulsion fracture of the Fibular head. The fracture fragment measures 5.2 mm in size on the image. The radiograph was taken at an SID of 48” and an OID of 4”. What is the actual size of the fracture fragment?
A. 4.77 mm
B. 0.94 mm
C. 5.67 mm
D. 1.09 mm
A. 4.77 mm
Which of the following factors impact subject contrast? (select all that apply)
- FSS
- OID
- SID
- kVp
- Grid use
- mAs
(2) OID
(4) kVp
(5) Grid use
Find the Geometric unsharpness of the following image: 80kVp, 25 mAS, 42” SID, 3” OID, 2.5 mm FS
A. 0.06 mm
B. 0.83 mm
C. 0.19 mm
D. 0.12 mm
C. 0.19 mm
Which of the following images has the worst spatial resolution?
A. 80 kVp, 20 mAs, 48” SID, 1” OID, 1.5 mm FS
B. 70 kVp, 16 mAs, 40” SID, 2” OID, 1.0 mm FS
C. 90 kVp, 12 mAs, 60” SID, 4” OID, 2.0 mm FS
D. 70 kVp, 20 mAS, 52” SID, 3” OID, 1.5 mm FS
C. 90 kVp, 12 mAs, 60” SID, 4” OID, 2.0 mm FS
An image is taken at an SID of 72” and the total exposure is 126 mR. If the SID is reduced to 46”, what will the new exposure be?
A. 51.4 mR
B. 308.7 mR
C. 197.2 mR
D. 80.5 mR
B. 308.7 mR
If an image taken at 40” SID generates an exposure of 250 mR, what distance would generate an exposure of 160 mR?
A. 72”
B. 36”
C. 50”
D. 42”
C. 50”
An image is taken at 64 mAs at an SID of 40” using a 12:1 grid. If the SID was changed to 48” and the grid were changed to 5:1, what should the new mAs be in order to maintain IR exposure?
A. 130 mAs
B. 53 mAs
C. 92 mAs
D. 37 mAs
D. 37 mAs
An image is taken at 72” SID using 80 kVp, 50 mAs and a 6:1 Grid. What should the new mAs be in order to maintain IR exposure if the SID were changed to 56” and the grid changed to a 8:1?
A. 20 mAs
B. 30 mAs
C. 82 mAs
D. 40 mAs
D. 40 mAs
A _____________ increase in kVp will cause the IR exposure to _____________
A. 15%, double
B. 15%, increase by 15%
C. 15%, be cut in half
D. 15%, decrease by 15%
A. 15%, double
An exposure is taken at 76 kVp and 25 mAs. Which of the following is the correct application of the 15% rule that would maintain IR exposure and reduce patient dose?
A. 65 kVp, 25 mAs
B. 65 kVp, 12.5 mAs
C. 87 kVp 25 mAs
D. 87 kVp, 12.5 mAs
D. 87 kVp, 12.5 mAs
An exposure is taken at 80 kVp, 20 mAs, 40” SID, and a 5:1 grid. If the radiographer switched to an 8:1 grid, what should the new technical parameters be in order to maintain IR exposure?
A. 92 kVp, 20 mAs
B. 80 kVp, 40 mAs
C. 80 kVp, 10 mAs
D. 68 kVp, 20 mAs
B. 80 kVp, 40 mAs
*use grid conversion formula