ENDTERM

Question 1

refers to the fidelity with which anatomic structure being examined is imaged on the radiograph.

Answer 1

Radiographic Quality

Question 2

faithfully reproduces structure and tissues

Answer 2

High - quality radiograph

Question 3

Important characteristics of radiographic quality are

Answer 3

spatial resolution
contrast resolution
noise
artifacts

Question 4

Ability to image 2 separate objects & visually distinguish one from the other

Answer 4

Resolution

Question 5

Ability to image small objects that have high contrast

Answer 5

Spatial resolution

Question 6

Examples of objects with high contrast

Answer 6

Bone-soft tissue interference
Breast calcification
Calcified long nodule

Question 7

What factors improve spatial resolution

Answer 7

Decreasing of:
screen blur
Motion blur
Geometric blur

Question 8

ability to distinguish anatomic structures of similar subject contrast

Answer 8

Contrast resolution

Question 9

Degree of density difference between two areas on a radiograph

Answer 9

Contrast resolution

Question 10

What diagnostic imaging has better contrast resolution than CT scan

Answer 10

MRI

Question 11

random fluctuation in the Optical density of the image

Answer 11

Noise

Question 12

results in a better radiographic image because it improves contrast resolution

Answer 12

Lower noise

Question 13

4 components of noise

Answer 13

Film graininess
Structure mottle
Quantum mottle
Scatter radiation

Question 14

refers to the distribution in size and space of silver halide grains in the emulsion.

Answer 14

Film graininess

Question 15

similar to film graininess but refers to the phosphor of the radiographic intensifying screen.

Answer 15

Structure mottle

Question 16

under the control of the radiologic technologist and is a principal contributor to radiographic noise in many radiographic imaging procedures.

Answer 16

Quantum mottle

Question 17

refers to the random nature by which x-rays interact with the image receptor.

Answer 17

Quantum mottle

Question 18

What reduces quantum mottle

Answer 18

High mAs
Low kVp
Slower image receptors

Question 19

Fast image receptors have…

Answer 19

High noise
Low spatial resolution
Low contrast resolution

Question 20

High spatial resolution and high contrast resolution require…

Answer 20

Low noise and slow image receptors

Question 21

Connected with resolution and noise

Answer 21

Speed/ Relative speed

Question 22

Interrelated characteristics of radiographic quality

Answer 22

Resolution
Noise
speed

Question 23

Graphic relationship between optical density and radiation exposure

Answer 23

Characteristic Curve

Question 24

Measurements used to describe the relationship between OD and radiation exposure.

Answer 24

H & D curve (Hurter & Driffield)
Sensitometric curve
D log E curve

Question 25

Portions of characteristic curve

Answer 25

Base plus fog Toe Straightline portion Shoulder Maximum density (Dmax)

Question 26

density at no exposure, or the density that is inherent in the film.

Answer 26

Base plus fog (b+f)

Question 27

Range of radiographic film base density

Answer 27

OD= 0.05 - 0.10

Question 28

What usually add OD 0.05 - 0.10 in fog density

Answer 28

Processing the film

Question 29

Total b+f is seldom below

Answer 29

OD 0.10 but not exceeding OD 0.22

Question 30

portion between the toe and shoulder

Answer 30

Straightline portion

Question 31

range of diagnostic densities varies from

Answer 31

< of OD 0.25–0.50 > of OD 2.0–3.0

Question 32

maximum density the film is capable of recording.

Answer 32

Dmax

Question 33

highest point on the D log E curve

Answer 33

Dmax

Question 34

Apparatus for Characteristic curve

Answer 34

Sensitometer Densitometer

Question 35

device used to measure optical density

Answer 35

Densitometer

Question 36

Both apparatus for characteristic curve are calibrated...

Answer 36

Annually

Question 37

Other term for sensitometer

Answer 37

Optical step wedge

Question 38

principal measurements in sensitometry

Answer 38

Film exposure Light percentage transmitted through processed film

Question 39

amount of overall blackness produced on the image after processing

Answer 39

Optical density / Density

Question 40

radiograph must have sufficient ______ to visualize the anatomic structures of interest

Answer 40

density

Question 41

Insufficient density leads to

Answer 41

Too light radiograph

Question 42

Excessive density leads to

Answer 42

Too dark radiograph Inability to visualize anatomic part