Fluoroscopy #2

Question 1

The fluoroscope was invented by?

Answer 1

Thomas Edison

Question 2

Dim objects can be viewed better?

Answer 2

With peripheral vision

Question 3

What structure is responsible for the vision of dim objects?

Answer 3

Rod

Question 4

The purpose of angiography is to do?

Answer 4

Visualize vessels

Question 5

In general, during fluoroscopy as compared with radiography?

Answer 5

The mA will be lower

Question 6

The cones are?

Answer 6

Used for photopic vision

Question 7

It is known that radiation can cause cataracts in which structure of the eye?

Answer 7

Lens

Question 8

During a fluoroscopic examination, static images are obtained on?

Answer 8

Spot film

Question 9

Visual acuity is the ability to do?

Answer 9

Perceive fine detail

Question 10

In a modern fluoroscope, the fluoroscopic x-ray tube?

Answer 10

Can be either under or over the table

Question 11

As compared with radiography, the x-ray technique required for fluoroscopy calls for?

Answer 11

Lower mA

Question 12

Which properties is associated with rods but not with cones?

Answer 12

Scotopic vision

Question 13

The rods are principally used for what?

Answer 13

Dim vision

Question 14

As compared with a radiographic examination, the primary purpose of a fluoroscopic examination is to visualize?

Answer 14

Dynamic images

Question 15

What ocular structures immediately precedes the vitreous humor along the path of incident light?

Answer 15

Lens

Question 16

Radiographic images?

Answer 16

Are viewed under photopic conditions

Question 17

The fovea centralis is?

Answer 17

Part of the retina

Question 18

Fluoroscopy normally requires a tube current of?

Answer 18

1 to 5 mA

Question 19

The Bucky slot cover of a fluoroscope is a?

Answer 19

Protective device

Question 20

During fluoroscopic imaging?

Answer 20

Reducing KVp increases image contrast

Question 21

Automatic brightness stabilization (ABS) is designed to compensate for which of the following?

Answer 21

Patient composition

Question 22

Video viewing of the fluoroscopic image is advantageous because?

Answer 22

The image is brighter

Question 23

What structure is most sensitive to colors?

Answer 23

Cones

Question 24

What describes the fluoroscopic system designed to maintain a constant image intensity?

Answer 24

Automatic brightness control (ABC)

Question 25

The function of the iris is to do?

Answer 25

Control the light level

Question 26

Photoelectric emission is?

Answer 26

Is the emission of electrons from an illuminated surface

Question 27

At what stage of image intensified fluoroscopy is the number of image forming photons lowest?

Answer 27

Entering the input phosphor

Question 28

Image intensifier brightness gain increases with increasing?

Answer 28

Flux gain

Question 29

When an image intensifier receives x-rays at the input phosphor, what is emitted at the output phosphor?

Answer 29

Visible light

Question 30

What is the input phosphor of image intensifiers?

Answer 30

Cesium iodide

Question 31

What is the output phosphor of image intensifiers?

Answer 31

Zinc cadmium sulfide

Question 32

The photocathode converts?

Answer 32

Visible light into electrons

Question 33

What is the component of the image intensifier responsible for focusing the electron beam?

Answer 33

The electrostatic lens

Question 34

The ability of an image intensifier to enhance image illumination is called?

Answer 34

Brightness gain

Question 35

The minification gain of an image intensifier increases with increasing?

Answer 35

Input phosphor size

Question 36

What is a representative brightness gain for an image intensifier?

Answer 36

20,000

Question 37

If an image intensifier is described as a 25/12 tube, 25/12 refers to which of the following?

Answer 37

The diameter of the input phosphor in centimeters

Question 38

In a 10/7/5 image intensifier?

Answer 38

The field of view is largest in the 10 mode

Question 39

An image intensifier has a 5 cm output phosphor and a 45 cm input phosphor. If the brightness gain is 10,000, the flux gain is approximately?

Answer 39

120

Question 40

Place the following in proper sequence for image intensified fluoroscopy:1. Electric signal to light 2. Electrons-to-light 3. Light-to-electric signal 4. Light-to-electrons 5. X-rays to light

Answer 40

5,4,2,3,1

Question 41

What applies to the output phosphor?

Answer 41

Light emitted

Question 42

What applies to the patient?

Answer 42

X-rays absorbed

Question 43

X-rays were initially discovered due to their ability to cause ?

Answer 43

fluorescence

Question 44

Prior to the development of the Image Intensifier, in order to enhance the brightness of the image during fluoroscopy, what step(s) had to be taken?

Answer 44

Increase the technique

Question 45

Of the following statements, which is correct concerning the rods?

Answer 45

They are sensitive to low levels of light

Question 46

The appearance of "ghost images" on the monitor during fluoroscopy is prevented by which of the following?

Answer 46

Having both the Input Phosphor and the Photocathode curved.