Question 1

If the SID doubles,the quantity of x-rays will increase:

Accepted Answer

When the Source-to-Image Distance (SID) doubles, the intensity of the x-ray beam at the image receptor is reduced according to the inverse square law. This means that if the SID is doubled, the quantity of x-rays reaching the image receptor is reduced to one-fourth of its original value. To maintain the same exposure, the quantity of x-rays produced would need to be increased 4 times.

Question 2

When a body part appears on a radiograph as longer than it actually is,the term used is:

Accepted Answer

Elongation occurs when the body part appears longer on the radiograph than it actually is, often due to improper alignment of the x-ray beam, the part being imaged, or the image receptor.

Question 3

When an image demonstrates many densities,and there is little difference between the densities,the image is described as having:

Accepted Answer

The answer of When an image demonstrates many densities,and there...

Question 4

Shape distortion is the result of:

Accepted Answer

Shape distortion is the result of unequal magnification of the actual shape of the structure. Tube angulation greater than 15 degrees, short or long SID can all cause size distortion.

Question 5

The geometric factors that affect the formation of the image are:
1) SID.
2) OID.
3) focal spot.

Accepted Answer

All three factors, Source-to-Image Distance (SID), Object-to-Image Distance (OID), and focal spot size, significantly influence the formation and quality of the image in radiographic imaging. SID affects the magnification and sharpness of the image, OID influences the magnification and clarity, and the focal spot size impacts the sharpness and resolution of the image.

Question 6

The term used in the new digital imaging environment to replace density is:

Accepted Answer

Brightness is the term used in digital imaging to describe the appearance of an image, which replaces the concept of density used in film radiography.

Question 7

Which of the following would be considered involuntary motion by the patient?
1) Tremors
2) Peristalsis
3) Breathing

Accepted Answer

Tremors and peristalsis are both examples of involuntary movements that the patient cannot control. Breathing, although necessary for life, can also be considered involuntary as it occurs automatically without conscious effort.

Question 8

The factors that affect x-ray quality are:
1) kilovoltage.
2) filtration.
3) mAs.

Accepted Answer

Kilovoltage and filtration affect the quality of x-rays. Kilovoltage affects the energy and penetration power of the x-rays, while filtration removes low-energy x-rays, improving the beam quality. mAs affects the quantity, not the quality, of x-rays.

Question 9

If the mA doubles,the quantity of exposure will:

Accepted Answer

The quantity of exposure is directly proportional to the mA. Therefore, if the mA is doubled, the quantity of exposure will also double.

Question 10

Fog is primarily caused by:

Accepted Answer

Fog on a radiographic image is primarily caused by scattered radiation, which can degrade the image quality by adding unwanted exposure (fog) not related to the anatomical area of interest.

Question 11

Tissue density refers to the ________ of the body part.

Accepted Answer

Tissue density refers to mass density or atomic number, which is a measure of the amount of matter in a given volume. This can have implications for medical imaging, as tissues with different densities will interact differently with radiation and can produce contrast that helps differentiate them on imaging studies. Tissue density does not specifically refer to the density of any one tissue type, such as muscle, fat, or bone.

Question 12

The primary controlling factor of penetration of x-rays is:

Accepted Answer

The primary controlling factor of penetration of x-rays is kVp, as it determines the energy of the photons produced and their ability to penetrate through tissues. mA and exposure time dictate the amount of radiation produced, while SID affects the intensity of the radiation, but neither have as direct an effect on penetration.

Question 13

When a body part appears on a radiograph as shorter than it actually is,the term used is:

Accepted Answer

Foreshortening is the term used to describe when a body part appears shorter on a radiograph than it actually is due to the angle of the x-ray beam. This can occur if the body part is not properly aligned or if the x-ray tube is not perpendicular to the body part being imaged.

Question 14

Contrast is directly influenced by:
1) SID.
2) fog.
3) collimation.

Accepted Answer

Fog and collimation directly influence contrast. Fog reduces contrast by adding unwanted density, while collimation improves contrast by reducing scatter radiation. SID primarily affects image sharpness and exposure, not contrast directly.

Question 15

When an image demonstrates little or low difference between the densities,the image is described as:

Accepted Answer

When an image demonstrates little or low difference between the densities, it is described as having low contrast. This means that the range of brightness levels between the lightest and darkest areas of the image is limited, resulting in a less detailed and less dynamic image.

Question 16

If the mA doubles,dose to the patient will:

Accepted Answer

The dose to the patient is directly proportional to the mA, which means that if the mA doubles, the dose will also double. Therefore, the correct answer is C, that is the dose will double.

Quiz 7: Principles of Exposure and Image Quality