Image Quality (Ch 10 - Bushong)

In a radiographic exam of the lumbar spine, which of the following techniques would result in the greatest exposure to the patient? a. 70 kVp, 200 mAs b. 80 kVp, 100 mAs c. 95 kVp, 50 mAs d. 110 kVp, 25 mAs e. 120 kVp, 25 mAs

a. 70 kVp, 200 mAs ( EXPOSURE = mAs )

Which of the following radiographic techniques is likely to produce the best visualization of low subject contrast structures? a. 72 kVp, 100 mA, 100 ms b. 84 kVp, 200 mA, 100 ms c. 93 kVp, 400 mA, 50 ms d. 100 kVp, 200 mA, 100 ms e. 107 kVp, 800 mA, 25 ms

a. 72 kVp, 100 mA, 100 ms ( kVp = contrast / image detail mAs = density ) ???

Which of the following technique charts requires accurate patient positioning? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

a. AEC

Which of the following technique charts requires no specific mAs selection? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

a. AEC

Accuracy in positioning the patient is most critical with which of the following? a. APR b. auto exposure c. fixed kV d. high kV e. variable kV

a. APR; b. auto exposure

When radiographic technique factors are adjusted to provide an acceptable image and then filtration is added to the x-ray tube, which of the following will increase? a. average energy of the x-ray beam b. optical density c. patient dose d. radiographic contrast e. spatial resolution

a. average energy of the x-ray beam ??? (don't understand this one)

Which of the following procedures would make best use of a high kV char? a. barium enema b. chest c. knee d. mammography e. pelvis

a. barium enema; b. chest

Distortion primarily occurs: a. because subject anatomy is inclined b. because subject anatomy is thick rather than thin c. when improper kVp was selected d. when subject anatomy is flat e. when subject anatomy lies parallel to the IR

a. because anatomy is inclined

Distortion: a. can be corrected by proper patient positioning b. is controlled by focal spot size c. never accompanies magnification d. occurs only lateral to the central axis of the x-ray beam e. occurs only when the image is inclined

a. can be corrected by proper patient positioning

Which of the following is not one of the geometric factors that affect radiographic quality? a. collimation b. distortion c. focal spot size d. magnification e. SID

a. collimation

The magnification factor is NOT dependent on: a. focal spot size b. OID c. SID d. SOD e. SSD

a. focal spot size

Which of the following does NOT affect subject contrast? a. grid ratio b. kVp c. mAs d. object shape e. object size

a. grid ratio; c. mAs

The chest represents high contrast anatomy (high subject contrast). Therefore, which of the following is most appropriate? a. high kVp b. high mAs c. long SID d. low kVp e. low mAs

a. high kVp

Radiographic contrast is increased by which of the following? a. increasing grid ratio b. raising kVp c. reducing the air gap d. reducing the heel effect e. using a slower film

a. increasing grid ratio

A longer greyscale on a radiograph can be obtained by doing which of the following? a. increasing kVp b. increasing mAs c. reducing kVp d. reducing mAs e. using a larger focal spot

a. increasing kVp

Which of the following is the procedure for selection of the kVp for a body part when the variable kV chart is used? a. measure the part, multiply by 2, then add 30 b. measure the part, multiply by 5, then add 30 c. preselect the kVp, then multiply the mAs by 2 d. preselect the kVp, multiply by 2, then add 20 e. preselect the kVp, multiply by 2, then add 30

a. measure the part, multiply by 2, then add 30

To minimize magnification, one should do which of the following? a. position the object as close to the IR as is practical b. position the x-ray tube as close to the patient as is practical c. use high kVp, low mAs d. use the large focal spot e. use the small focal spot

a. position the object as close to the IR as is practical

To reduce magnification, one should do which of the following? a. reduce OID b. reduce SID c. reduce SSD d. use the small focal spot size e. use tighter collimation

a. reduce OID

Which of the following contributes the LEAST to image distortion? a. a thick object at a short SID b. a thin object at a long SID c. angling of the CR d. object position e. off-axis imaging

a. thin object, long SID

In magnification radiography, when the object is placed equidistant between the source and the image receptor, the size of the image will be: a. 1.33 times object size b. 2 times object size c. 4 times object size d. one-half object size e. the same size as the object

b. 2 times object size

If other factors remain constant, which of the following would result in the highest optical density? a. 100 mA, 750 ms, 90 SID b. 200 mA, 500 ms, 90 SID c. 300 mA, 300 ms, 100 SID d. 400 mA, 200 ms, 100 SID e. 500 mA, 100 ms, 100 SID

b. 200 mA, 500 ms, 90 SID ??? (don't understand this one)

In the diagnostic x-ray range, the smallest change in kVp that can be perceived on the image is: a. 2 kVp b. 4 kVp c. 6 kVp d. 8 kVp e. 12 kVp

b. 4 kVp

The magnification factor increases with increasing: a. focal spot size b. OID c. SID d. SOD e. SSD

b. OID

Which of the following is principle reason for using direct exposure radiography? a. better resolution of low contrast tissues b. better spatial resolution c. higher contrast d. less motion blur e. lower patient dose

b. better spatial resolution

Before a radiographic technique chart is prepared, which of the following would be most important? a. calculation the mAs distance rule b. calibrating the x-ray imaging system c. marking all kVp stations on the control panel d. marking each IR e. measuring the part size with calipers

b. calibrating the x-ray system

Use of contrast media principally affects which of the following? a. blur b. contrast resolution c. mass density d. optical density e. speed

b. contrast resolution

Reducing field size through proper collimation usually results in improved: a. blur b. contrast resolution c. magnification d. patient dose e. spatial resolution

b. contrast resolution; d. patient dose

Geometric blur is controlled principally by which imaging system characteristic? a. contrast resolution b. focal spot size c. noise d. sensitivity e. spatial resolution

b. focal spot size

Spatial resolution is principally affected by which of the following? a. film speed b. focal spot size c. kVp d. mAs e. screen speed

b. focal spot size

Which of the following is MOST responsible for radiographic spatial resolution? a. film graininess b. focal spot size c. screen mottle d. SID e. use of a grid

b. focal spot size

If a radiographic technique calling for 100 mA at 100 ms is changed to 50 mA at 2000 ms: a. grayscale contrast will become longer b. grayscale contrast will become shorter c. there will be no change in grayscale contrast d. there will be no change in exposure time e. there will be no change in the x-ray tube capacity

b. grayscale contrast will become shorter ??? (don't understand this one)

When radiographic technique factors are adjusted to obtain an acceptable image, patient dose INCREASES as which of the following increases? a. film speed b. grid ratio c. SID d. SOD e. SSD

b. grid ratio

In general, a chest radiograph should be taken with: a. a generalization about this is not possible; decisions are dependent on thickness b. high kVp, high mAs c. high kVp, low mAs d. low kVp, high mAs e. low kVp, low mAs

b. high kVp, high mAs

When proper radiographic detail cannot be obtained because of a large OID, what change in technique may be used to improve the detail? a. increase IR speed b. increase SID c. increase time d. reduce kVp e. reduce mAs

b. increase SID

An upper gastrointestinal image demonstrates motion blur. To increase image detail, the radiologic technologist could do what? a. increase grid ratio b. increase kVp and reduce exposure time c. increase mA and exposure time d. reduce OID e. reduce SID

b. increase kVp and reduce exposure time

Penetration of the anatomic part by the x-ray beam can best be controlled by which of the following? a. calibration of the equipment b. kVp c. mAs d. measurement of the part e. tissue thickness

b. kVp

The anatomic part must be measured for variable kVp technique because a change will be required in which of the following? a. added filtration b. kVp c. mAs d. SID e. SSD

b. kVp

Which of the following does NOT affect image blur? a. focal spot size b. kVp c. OID d. SID e. SOD

b. kVp

When one images an object lateral to the central axis of the x-ray beam, the FSB will be: a. larger on the anode side b. larger on the cathode side c. magnified d. reduced e. the same as on the central axis

b. larger on the CATHODE side

To obtain minimum magnification, one should do which of the following? a. make sure the object is positioned on the central axis b. position the anatomy close to the IR c. select a short SID d. select a short SSD e. use maximum collimation

b. position the anatomy close the IR

Which of the following is the main component of radiographic noise? a. graininess b. quantum mottle c. random mottle d. structure mottle e. uniform mottle

b. quantum mottle

Subject contrast is: a. film contrast minus radiographic contrast b. radiographic contrast divided by film contrast c. radiographic contrast minus film contrast d. radiographic contrast times film contrast e. the sum of radiographic contrast and film contrast

b. radiographic contrast divided by film contrast ( rad contrast = IR contrast x subject contrast --> subject contrast = rad / film )

When an object is present to one side of the central axis of the x-ray beam: a. distortion will disappear b. subject contrast will remain unchanged c. the magnification factor will be larger d. the magnification factor will be smaller e. the magnification factor will remain unchanged

b. subject contrast will remain unchanged; e. magnification factor will remain unchanged

For a given anatomic part, the smallest change in mAs that can be perceived on the image is: a. 5% b. 15% c. 30% d. 50% e. 70%

c. 30%

Image magnification increases with increasing: a. image size b. object size c. OID d. SID e. SOD

c. OID

Which of the following technique charts requires accurate measurement? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

c. fixed kV; d. high kV; e. variable kV

Which of the following is most often influenced by focal spot size? a. absorption blur b. contrast resolution c. geometric blur d. motion blur e. patient dose

c. geometric blur

Which of the following radiographic techniques should result in the widest exposure latitude? a. high kVp, contrast film, high grid ratio b. high kVp, direct exposure, high grid ratio c. high kVp, latitude film, low grid ratio d. low kVp, direct exposure, high grid ratio e. low kVp, screen film, low grid ratio

c. high kVp, latitude film, low grid ratio

When fixed kVp technique is used for various anatomic thickness, a change will be required in which of the following? a. added filtration b. kVp c. mAs d. SID e. SSD

c. mAs

With other factors constant, optical density will increase with increasing: a. focal spot size b. grid ratio c. mAs d. SID e. SSD

c. mAs

An intravenous pyelogram (IVP) is routinely conducted with an AP projection to: a. improve contrast resolution b. maximize the effect of the contrast agent c. minimize the focal spot blur of the kidneys d. reduce the dose e. use the lowest kVp possible

c. minimize the focal spot blur of the kidneys

Absorption blur can be reduced by which of the following? a. increasing OID b. increasing kVp c. patient compression d. decreasing SID e. use of contrast media

c. patient compression

Which factor most often reduces the visualization of low contrast structures on a properly exposed radiograph? a. focal spot size b. grid ratio c. patient motion d. type of film e. type of screen

c. patient motion

An AP exam of the abdomen is taken at 80 kVp, 50 mAs, and 100 SID. If the scale of contrast is to be shortened, the radiographic tech must do which of the following? a. increase both mAs and kVp b. reduce both mAs and kVp c. reduce kVp and increase mAs d. reduce mAs and increase kVp e. shorten the SID

c. reduce kVp and increase mAs

Focal spot blur can be reduced by: a. increasing focal spot size b. increasing processing time or temp c. reducing OID d. reducing SID e. reducing SSD

c. reducing OID

Image magnification can be reduced with the use of which of the following? a. a cone b. increased filtration c. shorter OID d. shorter SID e. shorter SSD

c. shorter OID

Which of the following technique charts provides the LEAST amount of patient radiation exposure? a. auto programmed radiography b. auto exposure c. fixed kilovoltage d. high kilovoltage e. variable kilovoltage

d. high kV

Which of the following will increase exposure latitude? a. auto exposure b. faster IR c. fixed kV chart d. high kV chart e. variable kV chart

d. high kV chart

Magnification is reduced by which of the following? a. increasing kVp b. increasing screen speed c. increasing SID and OID d. increasing SID and reducing OID e. reducing focal spot size

d. increasing SID and reducing OID

The optical density present on the radiograph can best be controlled by which of the following? a. collimation b. focal spot size c. kVp d. mAs e. measurement of the part

d. mAs

Distortion of an x-ray image results from unequal: a. exposure of the object b. focal spot c. heel effect d. magnification e. SID

d. magnification

When the mAs is adjusted to provide constant optical density after an increase in kVp: a. absorption blur is reduced b. geometric blur is reduced c. latitude is reduced d. motion blur is reduced if the same mA is used e. spatial resolution will improve

d. motion blur is reduced if the same mA is used

Absorption blur is most closely related to which of the following? a. film blur b. focal spot blur c. geometric blur d. object shape e. screen blur

d. object shape

Another term for focal spot blur is: a. actual focal spot b. disumbra c. effective focal spot d. penumbra e. umbra

d. penumbra

Sharpness of detail on a radiograph is principally improved by which of the following? a. increasing kVp b. increasing scatter radiation c. reducing image noise d. reducing patient motion e. reducing radiation dose

d. reducing patient motion

The anatomic part to be examined must be measure because: a. a change in focal spot may be required b. a different IR may be required c. the mass density of the part is determined by the thickness d. the selected radiographic technique depends on anatomy thickness e. the SSD changes with anatomy thickness

d. technique depends on anatomy thickness

Certain areas in a radiograph appear blurred while others are sharp. The radiologic technologist probably can adjust for this by doing? a. increasing SID b. reducing mAs and increasing kVp c. reducing OID d. using a different cassette e. using a smaller focal spot

d. using a different cassette

Subject contrast is enhanced with the use of contrast media because: a. absorption blur is reduced b. Compton effect is increased c. focal spot blur is reduced d. mass density is increased e. photoelectric interaction is increased

e. PE interaction is increased

INCREASING which of the following is effective in REDUCING focal spot blur? a. focal spot size b. kVp c. object size d. OID e. SID

e. SID

Which of the following anatomic structures should exhibit the greatest subject contrast with muscle? a. bladder b. heart c. kidney d. liver e. lung

e. lung

A radiograph that exhibits a long grayscale contrast has which of the following features? a. few shades of gray that have great differences b. few shades of gray that have minimal differences c. good spatial resolution d. many shades of gray that have great differences e. many shades of gray that have minimal differences

e. many shades of gray that have minimal differences

Motion blur gets worse with increasing: a. field size b. grid ratio c. IR speed d. kVp e. patient movement

e. patient movement

When the focal spot is switched from large to small: a. focal spot blur will be greater on the anode side b. kVp must be increased for the same optical density c. mAs must be increased for the same optical density d. motion blur will be enhanced e. penumbra will be reduced

e. penumbra will be reduced

The Which of the following will reduce motion blur? a. long exposure time b. short SID c. increased kVp d. increased mAs e. proper patient instructions

e. proper patient instructions

Short exposure times are recommended for radiography of the stomach to do which of the following? a. enhance contrast b. improve spatial resolution c. minimize geometric blur d. reduce magnification e. reduce motion blur

e. reduce motion blur

Geometric blur can be reduced by which of the following? a. improving film-screen contact b. increasing processing time or temp c. increasing SID and OID d. increasing SSD and OID e. reducing focal spot size

e. reducing focal spot size

A foreshortened image: a. can be corrected by increasing kVp and reducing mAs b. can be corrected by reducing kVp and increasing mAs c. can be corrected by reducing SID d. can never be smaller than the object e. results from an inclined object

e. results from an inclined object

A radiograph that shows a relative lack of focal spot blur would be: a. high in contrast b. low in distortion c. low in optical density d. magnified e. sharp in detail

e. sharp in detail

Extremity x-ray exams result in which of the following? a. high distortion b. high noise c. high patient dose d. long scale contrast e. short scale contrast

e. short scale contrast

Which of the following is a basic characteristic of the variable kV chart? a. large focal spot b. long scale of contrast c. low mAs selection d. short exposure time e. short scale of contrast

e. short scale of contrast

Radiographic spatial resolution is improved by the use of which of the following? a. a grid b. larger focal spot c. reduced kVp d. reduced mAs e. slower radiographic intensifying screens

e. slower intensifying screens

The best way to minimize focal spot blur without affecting optical density is to use a very: a. high contrast IR b. long OID c. long SSD d. short SID e. small focal spot

e. small focal spot

The sharpness of detail in a radiograph is best increased by the use of which of the following? a. high-speed screens b. large focal spot c. long SID d. medium-speed screens e. small focal spot

e. small focal spot

Image contrast is the product of image receptor contrast and: a. focal spot contrast b. grid contrast c. resolution d. screen contrast e. subject contrast

e. subject contrast

Which of the following is a function of optimizing contrast? a. to control detail sharpness b. to control quantum mottle c. to determine optical density d. to improve spatial resolution e. to make detail visible

e. to make detail visible

To improve bony detail in a radiograph, the radiologic technologist could: a. decrease kVp and mAs b. decrease kVp and SID c. decrease SID and mAs d. use a faster screen e. use a smaller focal spot

e. use a smaller focal spot

A radiographic technique that would ensure visibility of detail for a cervical spine is: a. increasing the OID b. reducing the SID c. reducing the SSD d. selecting the large focal spot size e. using a beam restriction device

e. using a beam restriction device

For a mobile abdomen exam, radiographic contrast can be increased by doing which of the following? a. increasing the kVp and decreasing the mAs b. increasing the OID c. increasing the SID d. using a faster IR e. using a high ratio grid

e. using a high ratio grid ??? (don't understand this one)

Focal spot blur can be reduced by which of the following? a. increasing kVp b. increasing mAs c. increasing the OID d. reducing the SOD e. using the small focal spot

e. using the small focal spot

Which of the following technique charts has the LEAST exposure latitude? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

e. variable kV

Which of the following technique charts has the SHORTEST scale of contrast? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

e. variable kV

Which of the following technique charts recommends a 2 kVp change for each centimeter of thickness? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

e. variable kV

Which of the following technique charts requires the highest patient radiation dose? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

e. variable kV

Which of the following technique charts results in HIGHER contrast? a. AEC b. combination fixed and variable c. fixed kV d. high kV e. variable kV

e. variable kV