Test Bank For Digital Radiography and PACS, 4th - 2023 All Chapters - 9780323826983.pdf

Test Bank for Digital Radiography and PACS, 4th
k k k k k k k



- 2023 All Chapters k k k k




Approximately % of the x-ray beam incident on the k k k k k k k k



patient is transmitted through the patient without interaction to beco
k k k k k k k k k



me part of the image-forming beam. - ANSWER ✔ ️ 1
k k k k k k k k k




The kinetic energy of photoelectrons in the image intensifier is
k k k k k k k k k



greatly increased by thek . - ANSWER k k k k k



✔ ️ potential difference across the tube
k k k k k




Beam restriction with a(n)
k k k



is only accurate at a f
k k k k k



ixed SID. - ANSWER ✔ ️ aperture diaphragm
k k k k k k




Compton scatter contributes to k . k k k



a.useful information k k



b.image noise k



c.useful information, image noise and image contrast d.i
k k k k k k k



mage contrast - ANSWER ✔ ️ image noise
k k k k k k




Decreasing the kVp will increase k k k k



.
a.Compton scatter
k k



b.patient dose c.opti k k



cal density
k



d.image noise - ANSWER ✔ ️ patient dose
k k k k k k




Contrast resolution is improved by k . k k k k



a.tight collimation, lowering kVp and patient compression b.pati
k k k k k k k



ent compression
k

,c.lowering kVp k



d.tight collimation - k k



ANSWER ✔ ️ tight collimation, lowering kVp and patient compression
k k k k k k k k k




What is the typical number of projections in DRT?
k k k k k k k k



a.41 to 60 k k



b.10 to 25 k k



c.1 to 9 k



d.26 to 40 - ANSWER ✔ ️ 10 to 25
k k k k k k k k




How can you improve image contrast with a heavy patient without inc
k k k k k k k k k k k



reasing patient dose? k k



a. Use tight collimation.
k k



b. Raise kVp and lower mAs. k k k k



c. lower kVp and raise mAs and use tight collimation d.Lo
k k k k k k k k k



wer kVp and raise mAs. -
k k k k k



ANSWER ✔ ️ a.Use tight collimation.
k k k k k




Lowering kVp patient dose and k image k k k k



contrast.
a.lowers; increases b.low k k



ers; decreases c.increase
k k



s; increases
k



d. increases; decreases - ANSWER ✔ ️ increases; increases k k k k k k




A grid is constructed with 40-μm strips and a 250-
k k k k k k k k k



μm interspace. What percentage of x-
k k k k k



rays incident on the grid will be absorbed by its entrance surface?
k k k k k k k k k k k




a.

,12.5%
b.
11.5%
c.
14%
d.
10% - ANSWER ✔ ️ 14
k k k k




A grid is fabricated of 25-
k k k k k



μm lead grid strips sandwiched between interspace material that is 3
k k k k k k k k k k



00-μm thick. The height of the grid is
k k k k k k k



1.2 mm. What is the grid ratio?
k k k k k k




a.
8:1
b.
16:1
c.
12:1
d.
4:1 - ANSWER ✔ ️ 4:1
k k k k




An aluminum step wedge is placed on a tissue phantom that is 20 cm
k k k k k k k k k k k k k k



thick and a radiograph is made. Without a grid, analysis of the radiogr
k k k k k k k k k k k k



aph shows a 1.7% contrast. With a 8:1 grid, radiographic contrast is
k k k k k k k k k k k k



2.4%. What is the contrast improvement factor of this grid?
k k k k k k k k k




a.
2.6
b.

, 1.9
c.
1.4
d.
2 - ANSWER ✔ ️ 1.4
k k k k




What is the brightness gain for a 17-cm image-
k k k k k k k k



intensifier tube with a flux gain of 100 and a 2.5-
k k k k k k k k k k



cm output phosphor?
k k




a.
4,000
b.
3,654
c.
4,624
d.
5,000 - ANSWER ✔ ️ 4624
k k k k




It is a safe practice to keep CR cassettes in a "radiation safe" are
k k k k k k k k k k k k k



a of an x-ray suite during exams.
k k k k k k



Select one: k



True
False - ANSWER ✔ ️ False
k k k k




Filtered back projection in DRT refers to
k k k k k k k .
a.spatial resolution b.imag k k



e reconstruction c.prepati
k k



ent collimation
k



d.beam filtration - k k



ANSWER ✔ ️ b. image reconstruction
k k k k k