film radiography and cassette

Question 1

What is film made of?

Answer 1

polyester based and emulsion, composed of silver halilde crystals suspended in gelatin

Question 2

Speed and contrast of film are based on what?

Answer 2

size of silver halide crystals and thickness of the emulsion

Question 3

Film should be stored at what temperatures and what humidity?

Answer 3

68-70 degrees and 40-60% humidity

Question 4

What are intensifying screens made of?

Answer 4

polyester base with an active layer of phosphors that produce visible light when struck by x-rays. Normally mounted inside the cassette in pairs for use with double emulsion film.

Question 5

Poor film screen may be verified by using what?

Answer 5

radiographing a wire mesh screen

Question 6

Developer solution in developer tank converts exposed silver bromide crystals (latent image) to what?

Answer 6

black metallic silver (visible image)

Question 7

What does the fixer solution in the fixer tank do?

Answer 7

clears and removes unexposed silver bromide crystals,stops development and hardens the emulsion.

Question 8

What does the washer in the washer tank do?

Answer 8

removes chemicals remaining on the film, then dryer drys the film.

Question 9

What does the transport system do?

Answer 9

Transports film through processor and agitates the chemistry

Question 10

What does the replenishment system do?

Answer 10

Adds fresh developer and fixer solution for each film as it is fed through the processor

Question 11

What does the recirulation system do?

Answer 11

Agitates and filters developer solution, stabalizes solution temperature, prevents stratification of chemicals in the tank.

Question 12

What does high developer temperature cause on the film?

Answer 12

fog

Question 13

What does contamination of the chemicals cause on the film?

Answer 13

chemical fog

Question 14

What causes film to appear milky?

Answer 14

poor fixer replenishment

Question 15

What determines the matrix size?

Answer 15

the number of pixels

Question 16

What is a pixel?

Answer 16

the smalles represented in a digital image

Question 17

What is a scintilator?

Answer 17

A material that absorbs x-ray energy and conterts that as visible light. TFT flat panel detectors use scintilators

Question 18

What is spatial resolution?

Answer 18

lp/mm lines per mm

Question 19

As speed class increases, noise does what, and exposure to the patient does what?

Answer 19

noise increases as speed increases, as speed decreases, patient exposure increases

Question 20

What is the “S” number with fuji, konica, and phillips?

Answer 20

inversely related to exposure. Normal range is 250 to 300 for trunk and 75 to 125 for extremities

Question 21

What is the exposure index? (kodak)

Answer 21

directly related to exposure. Opitmal range is 1800-1900

Question 22

When using a grid, what must be compensated, mAs or kVp?

Answer 22

kVp- to limit patient dose.

Question 23

When should a grid be used?

Answer 23

With a chest more than 24 cm and anything else larger than 12 cm

Question 24

The primary controlling factors of density are what?

Answer 24

mAs and window level

Question 25

Are mAs and denisty directly proportional?

Answer 25

Yes

Question 26

The number of electrons boiled off the cathode and the number of x-rays produced are controlled by what?

Answer 26

mAs

Question 27

What is the law that states any combinations of mA and time that produce the same mAs value will produce the same radiographic denisty?

Answer 27

reciprocity law

Question 28

What does mAs directly control in the x-ray tube?
quantity and quality at the anode:
quantity and quality at the cathode?
energy of emission spectrum?
the quantities of x-rays produced?

Answer 28

the quantity of x-rays produced