Presbyopia

Question 1

Millodot (2007)

Answer 1

Refractive condition which accom of the eye is insufficiency for near vision work, due to aging

Question 2

Wolffsohn & Davies (2019)

Answer 2

> 40yrs unable to binoc. read N8 at 40cm or their habitual working distrance

Question 3

What are the risk factors of presbyopia?

Answer 3

• Age
• Health e.g. +ve, diabetes, MS or cardiovascular disease
• Drugs e.g. antidepressants, antihistamines and diuretics

Question 4

Why do we need the lens to change shape in accommodation?

Answer 4

We need it to adjust focal length as the distance between cornea and retina is stable

Question 5

When is the lens discoid shaped?

Answer 5

At rest

Question 6

What do meridional fibres do?

Answer 6

Pull the choroid and ciliary body forward

Question 7

What do circular fibres do?

Answer 7

Pull the ciliary body inwards

Question 8

Charman (2008)

Answer 8

Generally presbyopia is accepted to be when amplitude of accommodation falls below 3D

Question 9

Wolffsohn et al. (2023)

Answer 9

Rx corrected for distance but insufficient to meet individual requirement for Nr VA

Question 10

Hess Gullstrand Theory

Answer 10

Constant amount of ciliary muscle contraction is required per dioptre of accommodative change
As amplitude of accomm reduces with lens changes, more of the ciliary muscle becomes latent and so further reduction of accom occurs

Question 11

Duane-Fincham Theory

Answer 11

Zonules direction of insertion affects where they’re pulling and is indirectly related to lens growth. With lens growth it migrates into zonular space

Question 12

Helmholtz Theory (1924)

Answer 12

Crystalline lens is affected (standard theory)

Question 13

What is the normal accommodation latency?

Answer 13

300 msec + additional stabilisation the following second. This is done by calculating the amount of retinal blur in order to change the ciliary muscle

Question 14

Hofstetter Formula (1950)
Expected Amplitude

Answer 14

18.5 - (0.3 x age in yrs)

or can do

Age^2 - (Age/4)

Question 15

Hofstetter Formula (1950)
Max. Amplitude

Answer 15

25 - (0.4 x age in yrs)

Question 16

Hofstetter Formula (1950)
Min. Amplitude

Answer 16

15 - (0.25 x age in yrs)

Question 17

What spectacle treatment is there for presbyopia?

Answer 17

• Reading gls
• Bifocals / Trifocals / Varifocals (start with +0.75 or +1D)

Question 18

What contact lens treatment is there for presbyopia?

Answer 18

• Bifocal
• Progressive
• Monovision (one for nr and one for distance, but at +2.25D binocularity is greatly reduced; Evans, 2007)

Question 19

Evans (2007)

Answer 19

One for nr and one for distance, but at +2.25D binocularity is greatly reduced

Question 20

What pharmacological treatment is there for presbyopia?

Answer 20

• Pilocarpine Hydrochloride ophthalmic solution
  Parasympathomimetic = pinhole
  Miosis from ACh not being broken down
  No mydriasis = bad in low light

Question 21

What surgical treatment is there for presbyopia?

Answer 21

Katz et al. (2021)
- Corneal inlays into stroma uniocularly
- Laser scleral microporation
- Scleral Expansion bands - expand sclera at ciliary body into zonular space
- Refractive Lens Exchange - cataract surgery for those with cataracts (good in high myopia like -20D). Can be accom or bifocal IOLs

Question 22

What nutritional treatment is there for presbyopia?

Answer 22

• Astaxanthin
• Lutein
• Docoahexaenoic acid