DIP L1 - Introduction to DIP

Question 1

Contraction of ciliary muscles does what?

Answer 1

Bulges the lens - makes the image focused on the retina. Remember this because when you bulge lens, it makes lens more “compact”; so more ‘focused’

Question 2

Photopic vs Scoptopic

Answer 2

Photopic - daylight - cones… think of photopic as “photo”; you usually take photos in colour now. Located near the fovea

Question 3

What are the parts of accommodation?

Answer 3

Contraction of ciliary muscles, constriction of the pupils, convergence of the eyeballs

Question 4

How many cones in eye?

Answer 4

6 million

Question 5

Define absorbed dose. Units?

Answer 5

The energy deposition in any medium by any type of ionising radiation. Units of Gray.

Question 6

What does 1Gy equal?

Answer 6

1 J/kg

Question 7

What is equivalent dose?

Answer 7

Radiation has different effect- depending on what radiation it is. Equivalent dose is absorbed dose x radiation weighting factor

Question 8

What is effective dose?

Answer 8

absorbed dose x radiation weighting factor x tissue weighting factor. MEasured in Sv