Question 1

When the central ray is angled, the structure situated _____ is projected the most.

Accepted Answer

When the central ray is angled, the structure that is farther away from the image receptor (IR) is projected the most because the angle causes a distortion in the projection, making objects further from the IR appear more elongated or projected than those closer to it.

Question 2

Anatomical relationships are affected by
1)varying degrees of patient obliquity and flexion.
2)off centering.
3)geometrical factors of magnification, elongation, and foreshortening.
4)similar structures of shape and size.

Accepted Answer

D

Question 3

What is the marker placement of the projection of lateral hand.

Accepted Answer

C

Question 4

Minimizing size distortion is accomplished by which of the following?
1)Using the longest feasible SID
2)Using the shortest possible OID
3)Decreasing the angle of the CR
4)Placing the part as close to the IR as possible

Accepted Answer

Minimizing size distortion is accomplished by using the shortest possible OID, which can be achieved by placing the part as close to the IR as possible. Also, using the longest feasible SID will help minimize size distortion. However, decreasing the angle of the CR is not relevant to minimizing size distortion. Therefore, option 2 is not correct.

Question 5

Good collimation practices result in which of the following?
1)Reduces histogram analysis errors
2)Clearly delineates the VOI
3)Improves the visibility of recorded details by reducing the amount of scatter radiation that reaches the IR
4)Decreases the radiation dosage by limiting the amount of scatter from the patient

Accepted Answer

Good collimation practices result in improving the quality of the image by clearly delineating the VOI (volume of interest), reducing scatter radiation that can cause image blurring and reducing radiation dose by eliminating the scatter emanating from outside the region of interest. It also reduces histogram analysis errors caused by inclusion of irrelevant areas in the image. Therefore, options 1, 2, and 3 are correct. However, option 4 is incorrect as reducing radiation dose is not the main goal of collimation, but rather a positive side effect.

Question 6

A small focal spot should be used for each of the following situations except when

Accepted Answer

A small focal spot should be used in situations where fine detail demonstration is important or where extremities are being imaged. However, a larger focal spot is more appropriate when the milliamperage setting is above 300, as this reduces the risk of overheating the anode. The patient's ability to control motion is unrelated to the choice of focal spot size.

Question 7

Elongation occurs in all of the following situations except when the

Accepted Answer

Elongation occurs when the central ray is angled with the part or when the IR is angled, but not when the central ray and IR are perpendicular and the part is angled.

Question 8

An image demonstrating motion and adequate density was obtained using 100 mA at 0.5 seconds. If the time is changed to 0.25 seconds, what mA should be used to maintain density?

Accepted Answer

To maintain the same density, the mAs must remain constant. We know that the original image was obtained using 100 mA at 0.5 seconds, which gives a mAs value of 50 mAs (100 mA x 0.5 s). If we want to reduce the exposure time to 0.25 seconds, we need to double the mA to maintain the same mAs value. Therefore, the new mA should be 200 mA (50 mAs / 0.25 s = 200 mA).

Question 9

Which guideline should be used to position the identification (ID) plate?

Accepted Answer

The answer of Which guideline should be used to position...

Question 10

Good collimation practices will do all of the following except

Accepted Answer

Good collimation practices will not reduce the visibility of recorded details. In fact, proper collimation can improve the visibility and sharpness of recorded details by decreasing scatter radiation and increasing contrast.

Question 11

What is the marker placement for the projection of PA cranium?

Accepted Answer

The marker is placed laterally on the side being identified to indicate the side of the patient that is being imaged.

Question 12

The patient demographic requirements for radiographic images include all of the following except

Accepted Answer

Technologist's identification is not typically required on radiographic images as part of patient demographic information.

Question 13

What is the marker placement for the projection of PA oblique vertebrae?

Accepted Answer

For the PA oblique vertebrae projection, the marker is placed laterally, identifying the side that is situated closer to the image receptor (IR). This helps in accurately identifying the orientation and side of the anatomy being imaged.

Question 14

Three images were obtained on the same structure with a computed radiography system. Image 1 was obtained using a 48-inch source-image receptor distance (SID) and a 5-inch object-image receptor distance (OID); image 2 was obtained using a 48-inch SID and a 3-inch OID; and image 3 was obtained with a 48-inch SID, a 3-inch OID, and a larger IR. Which image will demonstrate the greatest size distortion?

Accepted Answer

Size distortion (magnification) in radiographic imaging is influenced by the source-image receptor distance (SID) and the object-image receptor distance (OID). The greater the OID, the more the size distortion. Since Image 1 has the largest OID (5 inches), it will demonstrate the greatest size distortion.

Question 15

What is the marker placement for the projection of lateral vertebrae?

Accepted Answer

The answer of What is the marker placement for the...

Question 16

Collimation guidelines include all of the following except for
1)chest and abdomen projections, collimate to within 1 inch (2.5 cm) of the patient's skin line.
2)extremity projections, collimate to within 0.5 inch (1.25 cm) of the skin line of the thickest VOI.
3)chest and abdomen projections, collimate to within 0.50 inch (1.25 cm) of the IR edge.
4)collimating structures within the torso, bring the collimated borders to within 1 inch (2.5 cm) of the VOI.

Accepted Answer

The answer of Collimation guidelines include all of the following...

Question 17

The medial and lateral femoral condyles are not superimposed on a lateral knee projection. The larger, lateral condyle is 1 inch (2.5 cm) anterior to the medial condyle. The best way to correct this error is to

Accepted Answer

The answer of The medial and lateral femoral condyles are...

Question 18

Which of the following is true about image markers?
1)They are radiopaque.
2)They should be reversed before being placed on the IR.
3)They should be positioned as close to the median plane as possible.
4)They will be magnified if positioned on the imaging table or patient.

Accepted Answer

1) Image markers must be radiopaque in order to be visible on the X-ray image.
2) Image markers do not need to be reversed before being placed on the IR.
3) Image markers should be positioned as close to the image receptor as possible, not necessarily the median plane.
4) Image markers will be magnified if positioned on the imaging table or patient, so they should be placed directly on the IR to avoid distortion.

Question 19

For an open joint space to be obtained, the central ray must be aligned _____ to the joint.

Accepted Answer

The answer of For an open joint space to be...

Question 20

Three images were obtained on the same structure with a computed radiography system. Image 1 was obtained using a 48-inch source-image receptor distance (SID) and a 5-inch object-image receptor distance (OID); image 2 was obtained using a 48-inch SID and a 3-inch OID; and image 3 was obtained with a 48-inch SID, a 3-inch OID, and a larger IR. Which image will demonstrate the sharpest recorded detail?

Accepted Answer

Image 2 will demonstrate the sharpest recorded detail because it has the smallest OID, which reduces geometric unsharpness. The use of a larger IR in Image 3 may allow for more anatomy to be included in the image, but it will not affect the sharpness of recorded detail. Image 1 has a larger OID than Image 2, which will result in more geometric unsharpness and a decrease in recorded detail.

Quiz 1: Guidelines for Image Analysis