4.1 Image Acquisition and Technical Evaluation
Which of the following are potential undesirable effect(s) of scattered radiation? 1. Image fog 2. Increased patient dose 3. Increased radiographer dose
1, 2, and 3
Which of the following can affect histogram appearance? 1. Centering accuracy 2. Positioning accuracy 3. Processing algorithm accuracy
1, 2, and 3
Which of the following can affect radiographic contrast? 1. LUT 2. Pathology 3. OID
1, 2, and 3
Which of the following can contribute to the image contrast? 1. Tissue density 2. Pathology 3. Muscle development
1, 2, and 3
Which of the following can minimize magnification seen in a radiographic image? 1. Long SID 2. Short OID 3. Compression
1, 2, and 3
Which of the following factors impact(s) spatial resolution? 1. Focal spot size 2. Subject motion 3. SOD
1, 2, and 3
Which of the following factors is/are related to grid efficiency? 1. rid ratio 2. Number of lead strips per inch 3. Amount of scatter transmitted through the grid
1, 2, and 3
Which of the following is (are) associated with subject contrast? 1. Patient thickness 2. Tissue density 3. Kilovoltage
1, 2, and 3
Exposure factors of 110 kVp and 12 mAs are used with an 8:1 grid for a particular exposure. What should be the new mAs if a 12:1 grid is substituted? A. 3 B. 9 C. 15 D. 18
15
An increase in kilovoltage in analog imaging is most likely to A. produce a longer scale of contrast B. produce a shorter scale of contrast C. decrease the receptor exposure D. decrease the production of scattered radiation
produce a longer scale of contrast
The relationship between the height of a grid's lead strips and the distance between them is referred to as grid
ratio
An exposure was made at 40-in. SID using 5 mAs and 105 kVp with an 8:1 grid. In an effort to improve image contrast, the image is repeated using a 12:1 grid and 90 kVp. Which of the following exposure times will be most appropriate, using 400 mA, to maintain the original receptor exposure? A. 0.01 s B. 0.03 s C. 0.1 s D. 0.3 s
0.03 s
A radiograph made using 300 mA, 0.1 second, and 75 kVp exhibits motion unsharpness, but otherwise satisfactory technical quality. The radiograph will be repeated using a shorter exposure time. Using 86 kV and 500 mA, what should be the new exposure time? A. 0.12 second B. 0.06 second C. 0.03 second D. 0.01 second
0.03 second
If 100 mA were selected for a radiographic exposure, what exposure time would be required to produce 5 mAs? A. 0.005 sec B. 0.02 sec C. 0.5 sec D. 0.05 sec
0.05 sec
A satisfactory radiograph of the abdomen was made at a 42-inch SID using 300 mA, 0.06-second exposure, and 80 kVp. If the distance is changed to 38 inches, what new exposure time would be required? A. 0.02 second B. 0.05 second C. 0.12 second D. 0.15 second
0.05 second
The exposure factors of 300 mA, 0.07 second, and 95 kVp were used to deliver a particular analog receptor exposure and contrast. A similar analog x-ray image can be produced using 500 mA, 80 kVp, and A. 0.01 second B. 0.04 second C. 0.08 second D. 0.16 second
0.08 second
Which of the following focal-spot sizes should be employed for magnification radiography? A. 0.2 mm B. 0.6 mm C. 1.2 mm D. 2.0 mm
0.2 mm
What pixel size has a 2,048 × 2,048 matrix with a 60-cm FOV? A. 0.3 mm B. 0.5 mm C. 0.15 mm D. 0.03 mm
0.3 mm
What pixel size has a 1024 × 1024 matrix with a 35-cm FOV? A. 30 mm B. 0.35 mm C. 0.15 mm D. 0.03 mm
0.35 mm
What pixel size has a 2048 × 2048 matrix with an 80-cm FOV? A. 0.04 mm B. 0.08 mm C. 0.2 mm D. 0.4 mm
0.4 mm
A grid is usually employed 1. when radiographing a large or dense body part 2. when using high kilovoltage 3. when less patient dose is required
1 and 2 only
A grid usually is employed in which of the following circumstances? 1. When radiographing a large or dense body part 2. When using high kilovoltage 3. When a lower patient dose is required
1 and 2 only
An analog x-ray exposure of a particular part is made and restricted to a 14 × 17 in. field size. The same exposure is repeated, but the x-ray beam is restricted to a 4 × 4 in. field. Compared with the first image, the second image will demonstrate 1. less receptor exposure 2. more contrast 3. more receptor exposure
1 and 2 only
An increase in kilovoltage will have which of the following effects? 1. More scattered radiation will be produced 2. The exposure rate will increase 3. Radiographic contrast will increase
1 and 2 only
An increase in the kilovoltage applied to the x-ray tube increases the 1. percentage of high-energy photons produced 2. beam intensity 3. patient absorption
1 and 2 only
Cassette-front material can be made of which of the following? 1. Carbon fiber 2. Magnesium 3. Lead
1 and 2 only
Compared to a low ratio grid, a high ratio grid will 1. absorb more of the useful beam 2. absorb more scattered radiation 3. allow more centering latitude
1 and 2 only
Which of the following pathologic conditions would require an increase in exposure factors? 1. Empyema 2. Osteoporosis 3. Pleural effusion
1 and 3 only
Disadvantages of moving grids over stationary grids include which of the following? 1. They can prohibit the use of very short exposure times 2. They increase patient radiation dose 3. They can cause phantom images when anatomic parts parallel their motion
1 and 2 only
Disadvantages of using lower kilovoltage technical factors, with mAs compensated to maintain receptor exposure, include 1. insufficient penetration 2. increased patient dose 3. diminished resolution
1 and 2 only
Exposure rate increases with an increase in 1. mA 2. kVp 3. SID
1 and 2 only
For which of the following examinations can the anode heel effect be an important consideration? 1. Lateral thoracic spine 2. AP femur 3. Right anterior oblique (RAO) sternum
1 and 2 only
Greater latitude is available to the radiographer in which of the following circumstances? 1. Using high-kV technical factors 2. Using a low-ratio grid 3. Using low-kV technical factors
1 and 2 only
Higher kVp settings can provide which of the following benefits? 1. Improved penetration 2. Patient dose reduction 3. Increased spatial resolution
1 and 2 only
In comparison with 60 kV, 80 kV will 1. permit greater exposure latitude 2. produce more scattered radiation 3. produce shorter-scale contrast
1 and 2 only
Low-kilovoltage exposure factors usually are indicated for radiographic examinations using 1. water-soluble, iodinated media 2. a negative contrast agent 3. barium sulfate
1 and 2 only
Phosphors classified as rare earth include 1. lanthanum oxybromide 2. gadolinium oxysulfide 3. cesium iodide
1 and 2 only
The effect that differential absorption has on radiographic contrast of a high-subject-contrast part can be minimized by 1. using a compensating filter 2, using high-kilovoltage exposure factors 3. increased collimation
1 and 2 only
Which of the following can have an effect on radiographic contrast? 1. Beam restriction 2. Grids 3. Focal spot size
1 and 2 only
Which of the following is (are) classified as rare earth phosphors? 1. Lanthanum oxybromide 2. Gadolinium oxysulfide 3. Cesium iodide
1 and 2 only
Which of the following methods can be used effectively to decrease differential absorption, providing a longer scale of contrast in the diagnostic range? 1. Using high peak kilovoltage and low milliampere-seconds factors 2. Using compensating filtration 3. Using factors that increase the photoelectric effect
1 and 2 only
Which of the following units is (are) used to express resolution? 1. Line-spread function 2. Line pairs per millimeter 3. Line-focus principle
1 and 2 only
Which of the following will improve the spatial resolution of image-intensified images? 1. A very thin coating of cesium iodide on the input phosphor 2. A smaller-diameter input screen/phosphor 3. Increased total brightness gain
1 and 2 only
Which one of the following is (are) used to control the production of scattered radiation? 1. Collimators 2. Optimal kV 3. Use of grids
1 and 2 only
With all other factors constant, as digital image matrix size increases, 1. pixel size decreases 2. resolution increases 3. pixel size increases
1 and 2 only
Which two (2) of the following statements are true regarding image distortion? 1. The least amount of image distortion occurs along the path of the CR 2. CR alignment has little/no impact on image distortion 3. X-ray tube angle impacts shape distortion 4. The least amount of image distortion occurs at the periphery of the x-ray beam 5. SID impacts shape distortion as well as size distortion
1 and 3 are correct
An anatomical part calls for a kilovoltage (kVp) setting necessary to penetrate the part. If a lower than acceptable kVp were selected using a fixed milliampere-seconds (mAs) setting, this would result in which of the following? 1. Increased patient dose 2. Increased exposure to the image receptor 3. Decreased penetration of the anatomical part
1 and 3 only
An increase in the milliamperage (mA) setting increases 1. X-ray beam quantity 2. X-ray beam quality 3. Image receptor exposure
1 and 3 only
Filtration of the radiographic x-ray beam functions to do which of the following? 1. Reduce patient skin dose 2. Decrease average beam energy 3. Provide uniform exposure of an anatomical part with different thicknesses
1 and 3 only
If a radiograph exhibits insufficient receptor exposure, this might be attributed to 1. insufficient kVp 2. insufficient SID 3. grid cutoff
1 and 3 only
If the x-ray image exhibits insufficient receptor exposure, this might be attributed to 1. Insufficient kilovoltage 2. Insufficient 3. SID grid cutoff
1 and 3 only
If x-ray beam filtration were not present, which of the following would be considered a negative effect? 1. Increased patient dose 2. Overexposure of the IR 3. Average energy of the x-ray beam would decrease
1 and 3 only
The factors that impact spatial resolution include 1. Focal spot size 2. Type of rectification 3. SID
1 and 3 only
Which of the following function(s) to reduce the amount of scattered radiation reaching the IR? 1. Grid devices 2. Restricted focal spot size 3. Beam restrictors
1 and 3 only
Which of the following imaging procedures do not require the use of ionizing radiation to produce an image? 1. Ultrasound 2. Computed axial tomography 3. MRI
1 and 3 only
Which of the following is (are) characteristic(s) of a 16:1 grid? 1. It absorbs more useful radiation than an 8:1 grid 2. It has more centering latitude than an 8:1 grid 3. It is used with higher-kilovoltage exposures than an 8:1 grid
1 and 3 only
Which of the following is affected by the size of the x-ray field? 1. Amount of scattered radiation produced 2. Motion unsharpness 3. Patient dose
1 and 3 only
Which of the following will contribute to the production of longer-scale radiographic contrast? 1. An increase in kV 2. An increase in grid ratio 3. An increase in photon energy
1 and 3 only
Which of the following will improve the sharpness of the edges of small anatomical parts? 1. Small focal spot size 2. Increased OID 3. Increased SID
1 and 3 only
A decrease from 90 to 77 kVp will result in an increase in 1. wavelength 2. gray scale 3. scattered radiation
1 only
A positive contrast agent 1. absorbs x-ray photons 2. results in a dark area on the radiograph 3. is composed of elements having low atomic number
1 only
According to the line-focus principle, an anode with a small angle provides 1. improved spatial resolution 2. improved heat capacity 3. less heel effect
1 only
An increase in kilovoltage with appropriate compensation of milliampere-seconds will result in 1. increased part penetration 2. higher contrast 3. increased receptor exposure
1 only
In radiography of a large abdomen, which of the following is (are) effective way(s) to minimize the amount of scattered radiation reaching the image receptor (IR)? 1. Use of optimal collimation 2. Use of low mAs 3. Use of a low-ratio rather than high-ratio grid
1 only
Spatial resolution is directly related to 1. source-image distance (SID) 2. tube current 3. focal spot size
1 only
The functions of automatic beam limitation devices include 1. reducing the production of scattered radiation 2. increasing the absorption of scattered radiation 3. changing the quality of the x-ray beam
1 only
The interaction between x-ray photons and matter illustrated in Figure 4-22 is most likely to be associated with 1. high kilovoltage 2. high contrast 3. high-atomic-number absorber
1 only
The sharpness of image details depends on all the following except 1. quantity of filtration 2. anode angle 3. OIDs
1 only
There is direct relationship between spatial resolution and 1. SID 2. tube current 3. focal-spot size
1 only
What are the effects of scattered radiation on a radiographic image? 1. It produces fog 2. It increases contrast 3. It increases grid cutoff
1 only
Which of the following examinations might require the use of 70 kV? 1. AP abdomen 2. Chest radiograph 3. Barium-filled stomach
1 only
Which of the following is (are) characteristic(s) of a 5:1 grid? 1. It allows some positioning latitude 2. It is used with high-kilovoltage exposures 3. It absorbs a high percentage of scattered radiation
1 only
Which of the following is (are) directly related to photon energy? 1. Kilovoltage 2. Milliamperes 3. Wavelength
1 only
A technique chart should be prepared for each AEC x-ray unit and should contain which of the following information for each type of examination? 1. Photocell(s) used 2. Optimum kilovoltage 3. Backup time
1, 2, and 3
Acceptable method(s) of minimizing motion unsharpness is (are) 1. suspended respiration 2. short exposure time 3. patient instruction
1, 2, and 3
Acceptable method(s) of minimizing motion unsharpness is (are) 1. suspended respiration 2. short exposure time 3. patient instruction
1, 2, and 3
Factor(s) that impact receptor exposure include 1. milliamperage 2. exposure time 3. kilovoltage
1, 2, and 3
For which of the following procedures must the radiographer carefully consider exposure time? 1. Patients who are unable to cooperate 2. UGI radiography 3. Lateral thoracic spine radiography
1, 2, and 3
Geometric unsharpness is influenced by 1. OID 2. SOD 3. SID
1, 2, and 3
Geometric unsharpness is influenced by which of the following? 1. Distance from object to image 2. Distance from source to object 3. Distance from source to image
1, 2, and 3
Geometric unsharpness will be least obvious 1. at long SIDs 2. with small focal spots 3. at the anode end of the image.
1, 2, and 3
In which of the following ways might higher image contrast be obtained in abdominal radiography? 1. By using lower kilovoltage 2. By using a contrast medium 3. By limiting the field size
1, 2, and 3
Shape distortion is influenced by the relationship between the 1. x-ray tube and the part to be imaged 2. body part to be imaged and the IR 3. IR and the x-ray tube
1, 2, and 3
The advantage(s) of high-kilovoltage chest radiography is (are) that 1. exposure latitude is increased 2. it produces long-scale contrast 3. it reduces patient dose
1, 2, and 3
The effect described as differential absorption is 1. responsible for radiographic contrast 2. a result of attenuating characteristics of tissue 3. minimized by the use of a high peak kilovoltage
1, 2, and 3
Which of the following is (are) characteristic(s) of a 16:1 grid? 1. It absorbs a high percentage of scattered radiation 2. It has little positioning latitude 3. It is used with high-kVp exposures
1, 2, and 3
Which of the following is likely to contribute to the radiographic contrast present on an analog x-ray image? 1. Atomic number of tissues radiographed 2. Any pathologic processes 3. Degree of muscle development
1, 2, and 3
Which of the following may be used to reduce the effect of scattered radiation on the radiographic image? 1. Grids 2. Collimators 3. Compression bands
1, 2, and 3
Which of the following pathologic conditions are considered additive conditions with respect to selection of exposure factors? 1. Osteoma 2. Bronchiectasis 3. Pneumonia
1, 2, and 3
Which of the following pathologic conditions require(s) a decrease in exposure factors? 1. Pneumothorax 2. Emphysema 3. Multiple myeloma
1, 2, and 3
Which of the following statements is (are) true with respect to the radiograph shown in Figure 4-29? 1. The image exhibits long-scale contrast 2. The image exhibits soft tissue fold 3. The image demonstrates motion blur
1, 2, and 3
A part whose width is 6 inches will be imaged at 44 inches SID. The part to be imaged lies 9 inches from the IR. What will be the magnification factor? A. 1.25 B. 1.86 C. 4.9 D. 7.3
1.25
If 300 mA has been selected for a particular exposure, what exposure time would be required to produce 60 mAs? A. 1/60 second B. 1/30 second C. 1/10 second D. 1/5 second
1/5 second
A satisfactory radiograph was made without a grid, using a 72-inch SID and 8 mAs. If the distance is changed to 40 inches and an 8:1 ratio grid is added, what should be the new mAs? A. 10 mAs B. 18 mAs C. 20 mAs D. 32 mAs
10 mAs
An exposure was made using 300 mA, 40 ms exposure, and 85 kV. Each of the following changes will cut the receptor exposure in half except a change to A. 1/50 sec exposure B. 72 kV C. 10 mAs D. 150 mA
10 mAs
Exposure factors of 100 kVp and 6 mAs are used with a 6:1 grid for a particular exposure. What should be the new milliampere-seconds value if a 12:1 grid is substituted? A. 7.5 mAs B. 10 mAs C. 13 mAs D. 18 mAs
10 mAs
Of the following groups of technical factors, which will produce the greatest receptor exposure? A. 10 mAs, 74 kV, 44-in. SID B. 10 mAs, 74 kV, 36-in. SID C. 5 mAs, 85 kV, 48-in. SID D. 5 mAs, 85 kV, 40-in. SID
10 mAs, 74 kV, 36-in. SID
Suppose a radiographer would normally use 5 mAs and 65 kVp on a neonate mobile AP abdomen radiograph using a non-grid DR detector array. However, upon arriving to the NICU, it is discovered that the neonate's abdomen is significantly distended due to ascites. The radiographer decides to use an 8:1 slip-on grid to reduce the amount of scatter radiation reaching the IR. Based on the condition of the patient and the use of an 8:1 grid, which of the following would be the best selection of technical factors the radiographer should use to maintain the desired exposure to the IR? A. 20 mAs, 65 kVp B. 10 mAs, 75 kVp C. 10 mAs, 65 kVp D. 12.5 mAs, 65 kVp
10 mAs, 75 kVp
A lateral radiograph of the cervical spine was made at 40 in. using 300 mA and 0.03 second exposure. If it is desired to increase the distance to 72 in., what should be the new milliampere (mA) setting, all other factors remaining constant? A. 400 mA B. 800 mA C. 1000 mA D. 1200 mA
1000 mA
What grid ratio is represented in Figure 4-8? A. 3:1 B. 5:1 C. 10:1 D. 16:1
10:1
A satisfactory radiograph was made using a 40-inch SID, 10 mAs, and a 12:1 grid. If the examination will be repeated at a distance of 48 inches and using an 8:1 grid, what should be the new mAs to maintain the original receptor exposure? A. 5.6 B. 8.8 C. 11.5 D. 14.4
11.5
In a PA projection of the chest being used for cardiac evaluation, the heart measures 15.2 cm between its widest points. If the magnification factor is known to be 1.3, what is the actual diameter of the heart? A. 9.7 cm B. 11.7 cm C. 19.7 cm D. 20.3 cm
11.7 cm
A satisfactory radiograph was made without a grid using a 72-in. SID and 8 mAs. If the distance is changed to 40 in. and an 12:1 ratio grid is added, what should be the new milliampere-seconds value? A. 9.5 mAs B. 12 mAs C. 21 mAs D. 26 mAs
12 mAs
In a posteroanterior (PA) projection of the chest being used for cardiac evaluation, the heart measures 14.7 cm between its widest points. If the magnification factor is known to be 1.2, what is the actual diameter of the heart? A. 10.4 cm B. 12.25 cm C. 13.5 cm D. 17.64 cm
12.25 cm
While using a digital radiography system, suppose a radiographer uses exposure factors of 10 mAs and 70 kVp with an 8:1 grid for an AP shoulder radiograph with acceptable anatomical part penetration and detector element (DEL) exposure. If the radiographer desires to increase scatter absorption using a 12:1 grid, what new exposure factors should be used to maintain the same DEL exposure? A. 15 mAs, 70 kVp B. 12.5 mAs, 70 kVp C. 7.5 mAs, 70 kVp D. 2.5 mAs, 70 kVp
12.5 mAs, 70 kVp
In order to double the x-ray quantity to the image receptor (IR) using kilovoltage-peak (kVp), the radiographer would need to raise the kVp by ______ percent. A. 5 B. 10 C. 15 D. 20
15
Exposure factors of 90 kVp and 4 mAs are used for a particular nongrid exposure. What should be the new mAs if an 8:1 grid is added? A. 8 B. 12 C. 16 D. 20
16
If a particular grid has lead strips 0.40 mm thick, 4.0 mm high, and 0.25 mm apart, what is its grid ratio? A. 8:1 B. 10:1 C. 12:1 D. 16:1
16:1
An exposure was made using 600 mA, 0.04 sec exposure, and 85 kVp. Each of the following changes will serve to reduce the receptor exposure by one-half except change to A. 1/50 sec exposure B. 72 kVp C. 18 mAs D. 300 mA
18 mAs
The average frequency of photons contained within the x-ray beam can be increased by 1. Increasing mAs 2. Increasing kVp 3. Increasing filtration 4. Decreasing kVp
2 and 3
A decrease from 80 mAs to 40 mAs will result in a decrease in which of the following? 1. Wavelength 2. Exposure rate 3. Beam intensity
2 and 3 only
Characteristics of high-ratio focused grids, compared with lower-ratio grids, include which of the following? 1. They allow more positioning latitude 2. They are more efficient in collecting SR 3. They absorb more of the useful beam
2 and 3 only
For an AP projection of the knee, if the patient is unable to fully extend the lower extremity, what could the radiographer do to minimize magnification distortion? 1. Use a compression band to extend the lower extremity 2. Increase the SID 3. Perform a PA projection
2 and 3 only
Spatial resolution can be improved by decreasing 1. the SID 2. the OID 3. patient/part motion
2 and 3 only
The term differential absorption is closely related to 1. beam intensity 2. subject contrast 3. pathology
2 and 3 only
Which of the following decrease attenuation of the x-ray beam? 1. Positive contrast agents 2. Air 3. Negative contrast agents
2 and 3 only
Which of the following refers to anatomical shape distortion? 1. Magnification 2. Elongation 3. Foreshortening
2 and 3 only
Which of the following statements is (are) most likely true regarding the figure below? 1. Image A was made using a higher kVp than image B 2. Image A was made with a higher ratio grid than image B 3. Image A demonstrates shorter scale contrast than image B
2 and 3 only
Which of the following statements is (are) true regarding Figure 7-10? 1. Excessive kilovoltage was used 2. High contrast is demonstrated 3. Insufficient penetration is evident
2 and 3 only
Which of the following statements is (are) true regarding the images below? 1. Image A was made using a higher kilovoltage than image B 2. Image A was made with a higher-ratio grid than image B 3. Image A demonstrates shorter-scale contrast than image B
2 and 3 only
A lateral (analog) radiograph of the lumbar spine was made using 200 mA, 1/2 second exposure, and 90 kV. If the exposure factors were changed to 200 mA, 0.25 second, and 104 kV, there would be an obvious change in which of the following? 1. Receptor exposure 2. Scale of grays/contrast 3. Distortion
2 only
Spatial resolution is inversely related to 1. SID 2. OID 3. grid ratio
2 only
The use of which of the following is (are) essential in magnification radiography? 1. High-ratio grid 2. Fractional focal spot 3. Direct exposure technique
2 only
Which of the following matrix sizes is most likely to produce the best image resolution? A. 128 × 128 B. 512 × 512 C. 1,024 × 1,024 D. 2,048 × 2,048
2,048 × 2,048
If the required technique is 10 mAs, 70 kVp, and the mA station is 500 mA, which of the following exposure times would be needed? A. 20 ms B. 33 ms C. 50 ms D. 100 ms
20 ms
If 85 kVp, 400 mA, and ⅛ s were used for a particular exposure using single-phase equipment, which of the following milliamperage or time values would be required, all other factors being constant, to produce a similar receptor exposure using high frequency multiphase equipment? A. 200 mA B. 800 mA C. 0.125 s D. 0.25 s
200 mA
Which of the following groups of exposure factors will produce the shortest scale of contrast? A. 200 mA, 0.25 s, 70 kVp, 12:1 grid B. 500 mA, 0.10 s, 90 kVp, 8:1 grid C. 400 mA, 0.125 s, 80 kVp, 12:1 grid D. 300 mA, 0.16 s, 70 kVp, 8:1 grid
200 mA, 0.25 s, 70 kVp, 12:1 grid
Of the following groups of exposure factors, which will produce the greatest receptor exposure? A. 400 mA, 30 ms, 72-in. SID B. 200 mA, 30 ms, 36-in. SID C. 200 mA, 60 ms, 36-in. SID D. 400 mA, 60 ms , 72-in. SID
200 mA, 60 ms, 36-in. SID
Using a 48-in. SID, how much OID must be introduced to magnify an object two times? A. 8-in. OID B. 12-in. OID C. 16-in. OID D. 24-in. OID
24-in. OID
An exposure was made using 600 mA and 18 ms. If the mA is changed to 400, which of the following exposure times would most closely approximate the original receptor exposure? A. 16 ms B. 0.16 second C. 27 ms D. 0.27 second
27 ms
The exposure factors of 400 mA, 70 ms, and 78 kV were used to produce a particular receptor exposure. A similar radiograph can be produced using 500 mA, 90 kV, and A. 14 ms B. 28 ms C. 56 ms D. 70 ms
28 ms
Both radiographic images seen in the figure below were made of the same subject using identical exposure factors. Which of the following statements correctly describes these images? 1. Image A illustrates less receptor exposure because a shorter SID was used 2. Image A illustrates more receptor exposure because the subject was turned PA 3. Image B illustrates more receptor exposure because a shorter SID was used
3 only
Both radiographic images shown in the figure below were made of the same subject using identical exposure factors. Which of the following statements correctly describe(s) these images? 1. Image A demonstrates less receptor exposure because a shorter SID was used 2. Image A demonstrates more receptor exposure because the subject was turned PA 3. Image B demonstrates more receptor exposure because a shorter SID was used
3 only
A 3-inch object to be radiographed at a 36-inch SID lies 4 inches from the image recorder. What will be the image width? A. 2.6 inches B. 3.3 inches C. 26 inches D. 33 inches
3.3 inches
If 82 kVp, 300 mA, and 0.05 second were used for a particular exposure using 3-phase, 12-pulse equipment, what mAs would be required, using single-phase equipment, to produce a similar radiograph? A. 7.5 B. 20 C. 30 D. 50
30
Which of the following fluoroscopic modes delivers the smallest patient dose? A. 30 cm field B. 25 cm field C. 12 cm field D. 9 cm field
30 cm field
If 0.05 second was selected for a particular exposure, what mA would be necessary to produce 15 mAs? A. 900 B. 600 C. 500 D. 300
300
Which of the following groups of exposure factors would be most appropriate for a sthenic adult IVU? A. 300 mA, 0.02 s, 72 kVp B. 300 mA, 0.01 s, 82 kVp C. 150 mA, 0.01 s, 94 kVp D. 100 mA, 0.03 s, 82 kVp
300 mA, 0.02 s, 72 kVp
If exposure factors of 85 kVp, 400 mA, and 12 ms yield an output exposure of 150 mR, what is the milliroentgens per milliampere-seconds (mR/mAs)? A. 0.32 B. 3.1 C. 17.6 D. 31
31
Exposure factors of 80 kVp and 8 mAs are used for a particular nongrid exposure. What should be the new milliampere-seconds value if an 8:1 grid is added? A. 16 mAs B. 24 mAs C. 32 mAs D. 40 mAs
32 mAs
A radiograph made using 300 mA, 0.1 second, and 75 kV exhibits motion unsharpness but otherwise satisfactory technical quality. The radiograph will be repeated using a shorter exposure time. Using 86 kV and 400 mA, what should be the new exposure time? A. 25 ms B. 37 ms C. 50 ms D. 75 ms
37 ms
If 84 kV and 8 mAs were used for a particular abdominal exposure with single-phase equipment, what milliampere-seconds value would be required to produce a similar radiograph with three-phase, 12-pulse equipment? A. 24 mAs B. 16 mAs C. 8 mAs D. 4 mAs
4 mAs
An x-ray image of the ankle was made at 40-SID, 200 mA, 50 ms, 70 kV, 0.6 mm focal spot, and minimal OID. Which of the following modifications would result in the greatest increase in magnification? A. 1.2 mm focal spot B. 36-in. SID C. 44-in. SID D. 4-in. OID
4-in. OID
Which of the following groups of technical factors would be most appropriate for the radiographic examination shown in Figure 4-30? A. 400 mA, 1/30 s, 72 kV B. 300 mA, 1/50 s, 82 kV C. 300 mA, 1/120 s, 94 kV D. 50 mA, ¼ s, 72 kV
400 mA, 1/30 s, 72 kV
The exposure factors used for a particular nongrid x-ray image were 300 mA, 4 ms, and 90 kV. Another image, using an 8:1 grid, is requested. Which of the following groups of factors is most appropriate? A. 400 mA, 3 ms, 110 kV B. 400 mA, 12 ms, 90 kV C. 300 mA, 8 ms, 100 kV D. 200 mA, 240 ms, 90 kV
400 mA, 12 ms, 90 kV
The exposure factors of 300 mA, 0.017 second, and 72 kVp produce an mAs value of A. 5 B. 50 C. 500 D. 5000
5
What is the spatial frequency of a digital system with a pixel pitch of 100 um? A. 10.0 lp/mm B. 5.0 lp/mm C. 0.05 lp/mm D. 0.01 lp/mm
5.0 lp/mm
A 5-in. object to be radiographed at a 44-in. SID lies 6 in. from the IR. What will be the image width? A. 5.1 in B. 5.8 in C. 6.1 in D. 6.7 in
5.8 in
Of the following groups of analog exposure factors, which is likely to produce the shortest scale of image contrast? A. 500 mA, 0.040 second, 70 kV B. 100 mA, 0.100 second, 80 kV C. 200 mA, 0.025 second, 92 kV D. 700 mA, 0.014 second, 80 kV
500 mA, 0.040 second, 70 kV
Which of the following groups of analog exposure factors is most likely to produce the longest scale of contrast? A. 200 mA, 0.25 second, 70 kVp, 12:1 grid B. 500 mA, 0.10 second, 90 kVp, 8:1 grid C. 400 mA, 0.125 second, 80 kVp, 12:1 grid D. 300 mA, 0.16 second, 70 kVp, 8:1 grid
500 mA, 0.10 second, 90 kVp, 8:1 grid
If 92 kV and 12 mAs were used for a particular abdominal exposure with single-phase equipment, what mAs would be required to produce a similar radiograph with three-phase equipment? A. 36 B. 24 C. 6 D. 3
6
If 92 kV and 12 mAs were used for a particular abdominal exposure with single-phase equipment, what mAs would be required to produce a similar radiograph with three-phase equipment? A. 36 B. 24 C. 8 D. 6
6
A satisfactory radiograph was made using a 36-in. SID, 12 mAs, and a 12:1 grid. If the examination will be repeated at a distance of 42 in. and using a 5:1 grid, what should be the new milliampere-seconds value to maintain the original receptor exposure? A. 5.6 B. 6.5 C. 9.7 D. 13
6.5
The exposure factors of 400 mA, 17 ms, and 82 kV produce a milliampere-seconds value of A. 2.35 B. 6.8 C. 23.5 D. 68
6.8
If 300 mA has been selected for a particular exposure, what exposure time should be selected to produce 18 mAs? A. 40 ms B. 60 ms C. 400 ms D. 600 ms
60 ms
If a duration of 0.05 second was selected for a particular exposure, what milliamperage would be necessary to produce 30 mAs? A. 900 B. 600 C. 500 D. 300
600
Which of the following groups of exposure factors would be most appropriate to control involuntary motion? A. 400 mA, 0.03 second B. 200 mA, 0.06 second C. 600 mA, 0.02 second D. 100 mA, 0.12 second
600 mA, 0.02 second
In an AP abdomen radiograph taken at 105-cm SID during an IVU series, one renal shadow measures 9 cm in width. If the OID is 18 cm, what is the actual width of the kidney? A. 5 cm B. 7.5 cm C. 11 cm D. 18 cm
7.5 cm
In an AP abdomen taken at 105-cm SID during an IV urography series, one renal shadow measures 9 cm in width. If the OID is 18 cm, what is the actual width of the kidney? A. 5 cm B. 7.5 cm C. 11 cm D. 18 cm
7.5 cm
An exposure was made using 300 mA and 50 ms. If the exposure time is changed to 22 ms, which of the following milliamperage selections would most closely approximate the original receptor exposure? A. 300 mA B. 400 mA C. 600 mA D. 700 mA
700 mA
A satisfactory radiograph of the abdomen was made at a 38-in. SID using 400 mA, 60-ms exposure, and 80 kV. If the distance is changed to 42 in., what new exposure time would be required? A. 25 ms B. 50 ms C. 73 ms D. 93 ms
73 ms
A part whose width is 6 inches will be imaged at 44 inches SID. The part to be imaged lies 9 inches from the IR. What will be the projected image width of the part? A. 8 inches B. 10 inches C. 12 inches D. 20 inches
8 inches
A particular radiograph was produced using 6 mAs and 110 kVp with an 8:1 ratio grid. The radiograph is to be repeated using a 16:1 ratio grid. What should be the new mAs? A. 3 B. 6 C. 9 D. 12
9
Which of the following are methods to prolong x-ray tube life? (select the three that apply) A. Perform the x-ray tube warm-up procedure when the anode is cold B. Use long exposure time settings C. Limit exposure prep time D. Avoid performing certain projections in the department's exam protocol E. Reduce repeat radiographs F. Keep the kVp setting constant for all exams
A, C, E
Which of the following factors are considered geometric factors that affect radiographic image quality? (select the three that apply) A. Magnification B. Kilovoltage C. Contrast resolution D. Distortion E. Focal-spot blur F. Exposure time
A, D, E
Which three of the following six pathologies require a reduction in technique during a radiographic examination: A. Osteoarthritis B. Pneumonia C. Osteopetrosis D. Emphysema E. Osteomalacia F. Atelectasis
A, D, E
A technologist prepares to perform an exam on an x-ray machine they have never used before. Which of the following three patient factors should be considered in the selection of appropriate kVp and mAs for an optimal image of the projections involved? A. Patient habitus B. SID C. Estimated part thickness D. Part composition E.Voltage waveform of the equipment F.Measured part thickness G.Beam filtration
A, D, F
Regardless of pixel size, which of the following factors influence spatial resolution? (select the two that apply) A. Focal spot selection B. kVp selection C. Adding a grid, with a compensating change in mAs D. Increasing collimation E. Changing SID
A, E
Which of the following radiographic examinations can use the anode heel effect to best advantage? A. AP foot B. AP knee C. PA skull D. AP thoracic spine
AP thoracic spine
How is SID related to exposure rate and receptor exposure? A. As SID increases, exposure rate increases and radiographic receptor exposure increases B. As SID increases, exposure rate increases and radiographic receptor exposure decreases C. As SID increases, exposure rate decreases and radiographic receptor exposure increases D. As SID increases, exposure rate decreases and radiographic receptor exposure decreases
As SID increases, exposure rate decreases and radiographic receptor exposure decreases
How is source-to-image distance (SID) related to exposure rate and receptor exposure? A. As SID increases, exposure rate increases and receptor exposure increases. B. As SID increases, exposure rate increases and receptor exposure decreases. C. As SID increases, exposure rate decreases and receptor exposure increases. D. As SID increases, exposure rate decreases and receptor exposure decreases.
As SID increases, exposure rate decreases and receptor exposure decreases.
Which of the following conditions will require an increase in x-ray photon energy/penetration? A. Fibrosarcoma B. Osteomalacia C. Paralytic ileus D. Ascites
Ascites
Which of the following pathologies would justify an increase in technique? A. Multiple myeloma B. Pneumothorax C. Emphysema D. Atelectasis
Atelectasis
The anode heel effect results in variation of the intensity of the beam across the field of view. Select four items from the list that will reduce the appearance of this variation on the displayed image. A. Smaller anode target angle B. Larger anode target angle C. Longer SID D. Automatic rescaling E. Flat fielding F. Aligning a tapering body part so that the thicker portion is on the anode side of the beam G. Aligning a tapering body part so that the thicker portion is on the cathode side of the beam
B, C, E, G
In digital radiography, patient information is displayed in the corners of the monitor for an exam. The 3 steps a technologist must take to ensure that the information is accurate are: A. Verify the patient's Identity by confirming their name and date of birth after the exam is complete. B. Verify the patient's Identity by confirming their name and date of birth before beginning the exam. C. Match the exam images to the Technologist Image number. D. Match the exam images to the exam accession number, either via query of the RIS worklist or manual entry. E.Verify the exam details with the patient. Confirm type of exam, body part to be examined, and side of the body are correct.
B, D, E
Receptor exposure decreases with an increase in (select the three that apply): A. kV B. SID C. focal spot size D. mAs E. part thickness F. grid ratio G. field size
B, E, F
From the following list, select the effective methods of reducing scatter radiation production in the patient (select the two that apply). A. Using an air-gap technique B. Increasing collimation C. Using a high ratio grid D. Using a direct conversion digital system E. Placing a lead apron over the anatomy of interest F. Using anatomical part compression
B, F
Which of the following is not considered a radiographic geometric factor? A. Magnification B. Focal spot size C. OID D. Beam filtration
Beam filtration
Which of the following represents the image acquisition contrast resolution? A. Pixel B. Pixel size C. Pixel pitch D. Bit depth
Bit depth
Which of the following terms is used to describe unsharp edges of tiny radiographic details? A. Diffusion B. Mottle C. Blur D. Umbra
Blur
What type of x-ray imaging uses an area beam and a photostimulable phosphor as the IR?
Computed radiography
Which of the following best describes the number of pixels per unit area? A. Pixel size B. Pixel pitch C. Pixel wide D. Pixel density
Pixel density
Causes of overexposure using AEC include (select the three that apply) A. insufficient backup time selected B. selected photocell is under tissue less dense than area of interest C. plus density control incorrectly selected D. required exposure time more than minimum response time E. selection of incorrect Bucky F. selected photocell is under a radiopaque appliance/prosthesis
C, E, F
Which of the following is NOT true of spatial resolution, FOV, and matrix size as they relate to each other? A. Increasing matrix size with no change to FOV will improve spatial resolution. B. Changing FOV has no effect on matrix size. C. Decreasing FOV with no other changes will improve spatial resolution. D. Changing matrix size has no effect on spatial resolution.
Changing matrix size has no effect on spatial resolution.
Which of the following devices is used to overcome severe variation in patient anatomy or tissue density, providing more uniform radiographic density? A. Compensating filter B. Grid C. Collimator D. Protective filter
Compensating filter
How would the introduction of a 6-in. OID affect analog image contrast? A. Contrast would be increased B. Contrast would be decreased C. Contrast would not change D. The scale of contrast would not change
Contrast would be increased
Which of the following measures the percentage of x-rays absorbed by the detector? A. FPD B. PPI C. DQE D. DXR
DQE
What is the best way to reduce magnification distortion?
Decrease OID
Which of the following combinations is most likely to be associated with quantum mottle? A. Decreased milliampere-seconds, decreased SID B. Increased milliampere-seconds, decreased kilovoltage C. Decreased milliampere-seconds, increased kilovoltage D. Increased milliampere-seconds, increased SID
Decreased milliampere-seconds, increased kilovoltage
If a lateral projection of the chest is being performed on an asthenic patient and the outer photocells are selected, what is likely to be the outcome? A. Decreased receptor exposure B. Increased receptor exposure C. Scattered radiation fog D. Motion blur
Decreased receptor exposure
Breast tissue is compressed in mammographic procedures to improve contrast resolution by reducing the production of Compton scatter. Which of the following also reduces Compton scatter production? A. Using a grid B. Increasing kVp C. Decreasing tissue density (mass/volume) D. Increasing average atomic number of tissue irradiated
Decreasing tissue density (mass/volume)
When describing the overall efficiency of CR photostimulabe phosphor plates converting x-ray signals into a useful image, which of the following terms best fit this definition? A. Modulation transfer function B. Detective quantum efficiency C. Absorption efficiency D. Conversion efficiency
Detective quantum efficiency
Each manufacturer's software system determines the gray scale available for when the x-ray image is displayed. Which of the following terms best describes this definition? A. Modulation transfer function B. Detective quantum efficiency C. Exposure latitude D. Dynamic range
Dynamic range
Which of the following techniques is used to evaluate the dynamics of a part? A. Fluoroscopy B. Stereoscopy C. Tomography D. Phototiming
Fluoroscopy
Which of the following is most likely to produce a high-quality image? A. Small image matrix B. High signal-to-noise ratio (SNR) C. Large pixel size D. Low resolution
High signal-to-noise ratio (SNR)
Which of the following technical changes would best serve to remedy the effect of very dissimilar tissue densities? A. Use of short exposure time B. Use of a high-ratio grid C. High-kilovoltage exposure factors D. High milliampere-seconds exposure factors
High-kilovoltage exposure factors
All the following statements regarding CR IPs are true except A. IPs have a thin lead foil backing B. IPs can be placed in the Bucky tray C. IPs must exclude all white light D. IPs function to protect the PSP
IPs must exclude all white light.
A patient is being positioned for a particular radiographic examination. The x-ray tube, image recorder, and grid are properly aligned, but the body part is angled. Which of the following will result? A. Grid cutoff at the periphery of the image B. Grid cutoff along the center of the image C. Increased receptor exposure at the periphery D. Image distortion
Image distortion
A technologist is about to perform a trauma cross-table cervical spine on a hypersthenic patient who is short of breath. As the technologist is setting up for the projection, it becomes clear that the patient will not be able to hold their breath through the exposure. How should the technologist adjust technique to preserve image quality? A. Change to a grid with a lower grid ratio. B. Use a shorter SID. C. Increase kVp by 15% and divided mA by 2. D. Increase kVp by 15% and divide exposure time by 2.
Increase kVp by 15% and divide exposure time by 2.
Which of the following is most likely to result from the introduction of a grid with appropriate technical factor change? A. Increased patient dose and increased scattered radiation fog B. Decreased patient dose and decreased scattered radiation fog C. Increased patient dose and decreased scattered radiation fog D. Decreased patient dose and increased scattered radiation fog
Increased patient dose and decreased scattered radiation fog
Which of the following is most likely to produce a radiograph with a long scale of contrast? A. Increased photon energy B. Increased OID C. Increased mAs D. Increased SID
Increased photon energy
In which of the following examinations should 70 kV not be exceeded? A. Upper GI (UGI) B. Barium enema (BE) C. Intravenous urogram (IVU) D. Chest
Intravenous urogram (IVU)
Grids improve the radiographic image by reducing the amount of scattered radiation fog. How does the use of grids impact exposure factors? A. It has no effect on exposure factors B. It increases exposure factors C. It decreases exposure factors D. It doubles exposure factors
It increases exposure factors
For which of the following examinations might the use of a grid not be necessary in an adult patient? A. Hip B. Knee C. Abdomen D. Lumbar spine
Knee
Which of the following terms/units is used to express the resolution of a diagnostic image? A. Line pairs per millimeter (lp/mm) B. Speed C. Latitude D. Kiloelectronvolts (keV)
Line pairs per millimeter (lp/mm)
A focal-spot size of 0.3 mm or smaller is essential for which of the following procedures? A. Bone radiography B. Magnification radiography C. Tomography D. Fluoroscopy
Magnification radiography
In which of the following examinations would a IR front with very low absorption properties be especially desirable? A. Extremity radiography B. Abdominal radiography C. Mammography D. Angiography
Mammography
Which of the following terms is used to express spatial resolution? A. Kiloelectronvolts (keV) B. Modulation transfer function (MTF) C. Relative speed D. Latitude
Modulation transfer function (MTF)
What is the single most important factor controlling size distortion?
OID
Which of the following pathologic conditions would require a decrease in exposure factors? A. Empyema B. Osteoporosis C. Pleural effusion D. Hemothorax
Osteoporosis
When an imaging department installs new radiographic equipment with higher DQE (Detective Quantum Efficiency) than previous equipment, the most important/valuable advantage is: A. Image quality improves. B. Repeat rates reduce. C. Exam throughput increases. D. Patient dose is reduced.
Patient dose is reduced
Which of the following best describes the distance from the center of one pixel to the center of the adjacent pixel? A. Pixel density B. Pixel size C. Pixel pitch D. Pixel wide
Pixel pitch
For a radiographic exposure of the femur, how should the anode heel effect be properly applied? A. Place the anode end of the x-ray tube over the proximal femur B. Place the cathode end of the x-ray tube over the distal femur C. Place the cathode end of the x-ray tube over the proximal femur D. Either the anode or cathode end of the x-ray tube could be placed over either end of the femur
Place the cathode end of the x-ray tube over the proximal femur
Which of the following pathologies would justify a decrease in technique? A. Ascites B. Pneumothorax C. Hydrocephalus D. Atelectasis
Pneumothorax
If insufficient x-ray quantity is supplied to a digital image receptor, which of the following will be seen on the final radiographic image? A. Decreased image brightness B. Increased contrast (shorter grayscale) C. Decreased spatial resolution D. Quantum mottle (noise)
Quantum mottle (noise)
Which of the following is most likely to occur as a result of using a 30-in. SID with a 14 × 17 in. IR to radiograph a fairly homogeneous structure? A. Production of quantum mottle B. Receptor exposure variation between opposite ends of the IR C. Production of scatter radiation fog D. Excessively short-scale contrast
Receptor exposure variation between opposite ends of the IR
Underexposure of a radiograph can be caused by all the following except insufficient
SID
Which of the following has the greatest effect on receptor exposure? A. Aluminum filtration B. Kilovoltage C. SID D. Scattered radiation
SID
A radiograph exposed using a 12:1 ratio focused grid may exhibit a loss of receptor exposure at its lateral edges because the A. SID was too great B. grid failed to move during the exposure C. x-ray tube was angled in the direction of the lead strips D. CR was off-center
SID was too great
If a radiograph exposed using a 12:1 ratio grid exhibits a loss of receptor exposure at its lateral edges, it is probably because the A. SID was too great B. grid failed to move during the exposure C. x-ray tube was angled in the direction of the lead strips D. central ray was off-center
SID was too great
Recently, dual-sided reading technology has become available in more modern CR readers, in which two sets of photodetectors are used to capture light released from the front and back sides of the phosphor storage plate, or PSP (photostimulable phosphor). This technology enables improved: A. Slow-scan direction speed B. Modulation transfer function C. Signal-to-noise ratio D. Fast-scan direction speed
Signal-to-noise ratio
The movement of the IP through the transport system of a CR reader is referred to as the: A. Slow-scan direction B. Charge-coupled direction C. Nyquist direction D. Fast-scan direction
Slow-scan direction
The radiographer receives an x-ray order for a 1-year-old child. Without adequate immobilization techniques or accessories such as a Pigg-O-Stat™, which of the following image qualities could be affected? A. Receptor exposure B. Contrast C. Spatial resolution D. Distortion
Spatial resolution
SID affects spatial resolution in which of the following way A. Spatial resolution is directly related to SID B. Spatial resolution is inversely related to SID C. As SID increases, spatial resolution decreases D. SID is not a spatial resolution factor
Spatial resolution is directly related to SID.
OID is related to spatial resolution in which of the following ways? A. Spatial resolution is directly related to OID. B. Spatial resolution is inversely related to OID. C. As OID increases, so does spatial resolution. D. OID is unrelated to spatial resolution.
Spatial resolution is inversely related to OID.
Better resolution is obtained with A. high SNR. B. low SNR. C. windowing. D. smaller matrix.
high SNR.
Which of the following is most closely related to the figure below? A. low kV B. high kV C. low mA D. high mA
high kV
If a 6-in. OID is introduced during a particular radiographic examination, what change in SID will be necessary to overcome objectionable magnification? A. The SID must be increased by 6 in B. The SID must be increased by 18 in C. The SID must be decreased by 6 in D. The SID must be increased by 42 in
The SID must be increased by 42 in..
When performing an axial projection, which of the following is NOT true? A. The amount of elongation distortion is affected by focal spot size. B. The amount of elongation distortion is affected by the alignment of the long axis of the object to the direction of the angle. C. The amount of elongation distortion is proportional to the size of the angle. D. The amount of elongation distortion is proportional to the object's OID.
The amount of elongation distortion is affected by focal spot size.
When an exposure is made using AEC but positioning is suboptimal, such that a portion of an active cell is struck by the primary beam, which of the following will occur? A. The exposure will terminate prematurely and the displayed image will have mottle in the regions where the anatomy is thickest. B. The exposure duration will be longer and the patient will receive excessive dose. C. The exposure will terminate as expected and the displayed image will show no adverse effects. D. The exposure duration will be longer and the displayed image will have mottle in the regions where the anatomy is thickest.
The exposure will terminate prematurely and the displayed image will have mottle in the regions where the anatomy is thickest.
A technologist setting a manual technique on a DR imaging system is contemplating changing mA from 300 down to 150, with no other changes to other factors. Which of the following effects will happen as a result of this change? A. The patient dose will double. B. The image will have increased brightness. C. The image will have a shorter scale of contrast. D. The signal-to-noise ratio will decrease.
The signal-to-noise ratio will decrease.
Occasionally, it is difficult for the radiographer to obtain a diagnostic image of the odontoid (dens) process using the open-mouth technique. An alternative method, called the Fuch's method, may be used where the patient extends their head to place the mental and mastoid plane perpendicular to the image receptor. However, if the patient is unable to obtain the full extension needed, a cephalic angulation of the x-ray tube may be warranted. What would be the potential disadvantage(s) of such an angulation of the tube? A.The chin would be projected cephalically to prevent superimposition over the odontoid process B.The odontoid process would appear within the opening of the foramen magnum C.The tube angulation would foreshorten the odontoid process and therefore may superimpose the borders of a fracture gap in such a way that the fracture may go undetected D.The thyroid dose would significantly increase
The tube angulation would foreshorten the odontoid process and therefore may superimpose the borders of a fracture gap in such a way that the fracture may go undetected
With milliamperage adjusted to produce equal exposures, all the following statements are true except A. a single-phase examination done at 10 mAs can be duplicated with three-phase, 12-pulse at 5 mAs. B. There is greater patient dose with three-phase equipment than with single-phase equipment. C. Three-phase equipment can produce comparable radiographs with less heat unit (HU) buildup. D. Three-phase equipment produces lower-contrast radiographs than single-phase equipment.
There is greater patient dose with three-phase equipment than with single-phase equipment
If an acceptable image is obtained utilizing 20 mAs, 75 kVp at a 40-in. SID, what adjustment must be made to mAs with a 35-in. SID to maintain image receptor exposure? A. Use 25 mAs, 75 kVp B. Use 15 mAs, 75 kVp C. Use 18 mAs, 75 kVp D. Use 5 mAs, 75 kVp
Use 15 mAs, 75 kVp
When the collimated field must extend past the edge of the body, allowing primary radiation to strike the tabletop, as in a lateral lumbar spine radiograph, what may be done to prevent excessive receptor exposure owing to undercutting? A. Reduce the milliampere-seconds. B. Reduce the kilovoltage. C. Use a shorter SID. D. Use lead rubber to absorb tabletop primary radiation.
Use lead rubber to absorb tabletop primary radiation.
Which of the following combinations will result in the most scattered radiation reaching the image receptor? A. Using more mAs and compressing the part B. Using more mAs and a higher ratio grid C. Using less mAs and more kVp D. Using less mAs and compressing the part
Using less mAs and more kVp
Which of the following best allows optimal visualization of both soft tissue and bony structures in a given image? A. Narrow dynamic range B. Wide dynamic range C. Brightness gain D. Structures recorded
Wide dynamic range
Which of the following errors is illustrated in the figure below? A. Patient not centered to IR B. X-ray tube not centered to grid C. Inaccurate collimation D. Unilateral grid cutoff
X-ray tube not centered to grid
Quantum mottle manifests within an image because A. there was not enough filtration of the primary beam B. too much scatter radiation was produced C. a grid was not employed to effectively clean up the scatter D. a poor signal was captured by the image receptor
a poor signal was captured by the image receptor.
Geometric unsharpness is most likely to be greater A. at long SIDs B. at the anode end of the image C. with small focal spots D. at the cathode end of the image
at the cathode end of the image
The reduction in x-ray photon intensity as the photon passes through material is termed
attenuation
Which of the following absorbers has the highest attenuation coefficient? A. Bone B. Muscle C. Fat D. Air
bone
The best way to control voluntary motion is A. immobilization of the part B. careful explanation of the procedure C. short exposure time D. physical restraint
careful explanation of the procedure
In amorphous selenium flat-panel detectors, the term amorphous refers to a A. crystalline material having typical crystalline structure. B. crystalline material lacking typical crystalline structure. C. toxic crystalline material. D. homogeneous crystalline material.
crystalline material lacking typical crystalline structure
A graphic diagram of signal values representing various absorption properties within the part being imaged is called a
histogram
Decreasing field size from 14 × 17 in. to 8 × 10 in., with no other changes, will A. decrease receptor exposure and decrease the amount of scattered radiation generated within the part B. decrease receptor exposure and increase the amount of scattered radiation generated within the part C. increase receptor exposure and increase the amount of scattered radiation generated within the part D. increase receptor exposure and decrease the amount of scattered radiation generated within the part
decrease receptor exposure and decrease the amount of scattered radiation generated within the part
Decreasing field size from 14 × 17 into 8 × 10 inches will A. decrease receptor exposure and increase the amount of scattered radiation generated within the part. B. increase receptor exposure and increase the amount of scattered radiation generated within the part. C. increase receptor exposure and decrease the amount of scattered radiation generated within the part. D. decrease receptor exposure and decrease the amount of scattered radiation generated within the part.
decrease receptor exposure and decrease the amount of scattered radiation generated within the part.
If a radiograph, made using AEC, is overexposed because an exposure shorter than the minimum response time was required, the radiographer generally should A. decrease the milliamperage B. increase the milliamperage C. increase the kilovoltage D. decrease the kilovoltage
decrease the milliamperage
A radiograph made with a parallel grid demonstrates decreased receptor exposure on its lateral edges. This is most likely due to A. static electrical discharge B. the grid being off-centered C. improper tube angle D. decreased SID
decreased SID
A 15% increase in kVp accompanied by a 50% decrease in mAs will result in
decreased patient dose
Radiographic contrast is the result of
differential absorption
What is the correct critique of the CR image shown in Figure 4-3?
double exposure
The radiograph shown in Figure 4-12 demonstrates an example of A. overexposure B. motion C. laser jitter D. exposure artifact
exposure artifact
All the following affect the exposure rate of the primary beam except A. milliamperage B. kilovoltage C. distance D. field size
field size
All the following have an impact on radiographic contrast except A. photon energy B. grid ratio C. OID D. focal-spot size
focal-spot size
Exposure values arising from excessive kV, insufficient collimation, or thick anatomic structures are termed
fog
The radiograph seen below illustrates incorrect use of
grid
What is the correct critique of the CR image seen below? A. double exposure B. grid centering error C. incorrect AEC photocell D. inverted focused grid
grid centering error
The absorption of useful radiation by a grid is called
grid cutoff
The radiograph shown in the image below exhibits a loss of receptor exposure as a result of A. x-ray tube angulation across grid lines B. exceeding the focusing distance C. incorrect grid placement D. insufficient SID
incorrect grid placement
A 15% decrease in kilovoltage accompanied by doubling the milliampere-seconds will result in a(n) A. increase in patient dose B. increase in exposure latitude C. decrease in receptor exposure D. decrease in spatial resolution
increase in patient dose
Using a short (25-30 in.) SID with a large (14 × 17 in.) IR is likely to A. increase the scale of contrast B. increase the anode heel effect C. cause malfunction of the AEC D. cause premature termination of the exposure
increase the anode heel effect
When involuntary motion must be considered, the exposure time may be cut in half if the kilovoltage is A. doubled B. increased by 15% C. increased by 25% D. increased by 35%
increased by 15%
If a 4-inch collimated field is changed to a 14-inch collimated field, with no other changes, the image receptor will experience A. decreased receptor exposure B. increased receptor exposure C. more spatial resolution D. less spatial resolution
increased receptor exposure.
X-ray energy is directly controlled by which of the following factors? A. kVp B. mAs C. SID D. OID
kVp
In preparing to use Automatic Exposure Control in combination with a PSP image receptor for an AP lumbar spine projection on a patient with a hypersthenic habitus, an optimal image can best be produced with which of the following changes to technical factors? A. kVp is decreased to compensate for decreased patient size. B. The outer cells of the AEC are active. C. The AEC calibration is adjusted via the "+" density controls on the control panel, creating a longer exposure. D. kVp is increased to compensate for increased part thickness.
kVp is increased to compensate for increased part thickness.
The image quality seen in the figure below is most likely the result of A. an off-level grid B. pronounced anode heel effect C. low-milliampere-seconds and high-kilovoltage factors D. low-kilovoltage and high-milliampere-seconds factors
low-milliampere-seconds and high-kilovoltage factors
How are mAs and receptor exposure related in the process of image formation? A. mAs and receptor exposure are inversely proportional B. mAs and receptor exposure are directly proportional C. mAs and receptor exposure are related to image unsharpness D. mAs and receptor exposure are unrelated
mAs and receptor exposure are directly proportional
To produce a just perceptible increase in receptor exposure in analog imaging, the radiographer should increase the
mAs by 30%
Which combination of exposure factors most likely will contribute to producing the shortest-scale contrast? A. mAs: 10; kV: 70; Grid ratio: 5:1; Field size: 14 × 17 in. B. mAs: 12; kV: 90; Grid ratio: 8:1; Field size: 14 × 17 in. C. mAs: 15; kV: 90; Grid ratio: 12:1; Field size: 11 × 14 in. D. mAs: 20; kV: 80; Grid ratio: 10:1; Field size: 8 × 10 in.
mAs: 20; kV: 80; Grid ratio: 10:1; Field size: 8 × 10 in.
Misrepresentation of the true size of an anatomical structure is called
magnification
A focal-spot size of 0.3 mm or smaller is essential for A. small-bone radiography B. magnification radiography C. long SID techniques D. fluoroscopy
magnification radiography
All the following are related to spatial resolution except A. milliamperage B. focal-spot size C. source-to-object distance D. OID
milliamperage
A particular milliampere-seconds value, regardless of the combination of milliamperes and time, will reproduce the same receptor exposure. This is a statement of the A. line-focus principle B. inverse-square law C. reciprocity law D. law of conservation of energy
reciprocity law
Combinations of milliamperage and exposure time that produce a particular milliampere-seconds value will produce identical receptor exposure. This statement is an expression of the
reciprocity law
The CR should be directed to the center of the part of greatest interest to avoid A. rotation distortion B. magnification C. foreshortening D. elongation
rotation distortion
The radiograph of the pelvis shown in the figure below is unacceptable because of A. motion B. inadequate penetration C. scattered radiation fog D. double exposure
scattered radiation fog
Misalignment of the tube-part-IR relationship results in
shape distortion
Changes in milliampere-seconds can affect all the following except A. quantity of x-ray photons produced B. exposure rate C. receptor exposure D. spatial resolution
spatial resolution
Which digital imaging characteristic is defined as the "sharpness of the structural edges recorded in an image"? (Carroll, Quinn B., 2nd ed., p.225)
spatial resolution
Figure 4-19 is representative of A. the anode heel effect B. the line-focus principle C. the inverse-square law D. the reciprocity law
the anode heel effect
Radiation spreads from a source in an expanding sphere, the area given by 4/3πr34/3πr3. So long as the rate of emission is constant, the intensity of the radiation will reduce by a factor squared as an observer moves away from the source. This describes
the inverse square law
As grid ratio is decreased, A. the scale of contrast becomes longer B. the scale of contrast becomes shorter C. receptor exposure decreases D. radiographic distortion decreases
the scale of contrast becomes longer
Compensating filters are radiographically useful in that A. they prevent unnecessary characteristic radiation from being produced. B. they provide more uniform exposure to anatomical parts having unequal thicknesses. C. they eliminate the need for internal and external filtration in the x-ray tube housing and collimator. D. they eliminate scatter production in the patient, thereby reducing image noise.
they provide more uniform exposure to anatomical parts having unequal thicknesses.
Compton scatter production and photoelectric absorption within the patient both increase at the same rate as
tissue thickness increases
Focal-spot blur is greatest A. toward the anode end of the x-ray beam B. toward the cathode end of the x-ray beam C. directly along the course of the CR D. as the SID is increased
toward the cathode end of the x-ray beam