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Question 1

3 + 9 o’clock staining causes

Answer 1

poor/thick edge design, small/large edge clearance, small/large TD, insufficient blinking

Question 2

3 + 9 o’clock staining symptoms

Answer 2

can be asymptomatic

irritation/dryness, reduced WT, redness

Question 3

3 + 9 o’clock staining management

Answer 3

cease CL wear

refit with thinner edge design, larger diameter lens, refit with GP toric lens if cornea >2DC, ocular lubricants, reduce WT

Question 4

what is dimple veil staining?

Answer 4

small indentations in epithelium due to air bubbles (RGPs) or mucin balls (SCLs) trapped under lenses

Question 5

dimple veil staining causes

Answer 5

excessive edge clearance (due to very steep or flat lens)

Question 6

dimple veil staining symptoms

Answer 6

asymptomatic to mild irritation, may disturb vision if on visual axis

Question 7

dimple veil staining management

Answer 7

flatter BOZR, smaller TD, change to toric back surface, ocular lubricants

Question 8

RGP designs

Answer 8

maxim - constant average thickness, ease of fit, high first lens success

quantum - best selling RGP, VA of spherical optical zone with aspheric periphery (more comfortable fit), minimise deposition, excellent oxygen transmissibility

Question 9

RGP material

Answer 9

ML92 (dK 33) - mid dk fluorosilicone acrylate, medium oxygen delivery, good protein resistance

XO2 (dk 141) - hyper dk fluorosilicone acrylate, outstanding oxygen permeability, excellent deposit resistance

Question 10

a difference of 0.1 in K readings is equivalent to what?

Answer 10

0.5D

Question 11

rule of thumb for RGP

Answer 11

for every 0.05mm the BOZR is steeper the tear lens power increases by 0.25D

increase TD by 1mm, flatten by 0.1mm

Question 12

blepharitis management

Answer 12

• chronic nature, ongoing treatment
• lid hygiene to wipe away bacteria/
  deposits from lid margins
• wet warm compresses loosen
  collarettes and crusts
• dry warm compresses melt meibum
• advice avoidance of cosmetics
• anterior 2nd line - CPL ointment bds rubbed into lid margin
• MGD 2nd line systemic tetracycline
• demodex - tea tree oil

Question 13

dry eye management

Answer 13

modification of local environment - VDU breaks, air con/heaters

tear supplements during day + unmedicated ointment for bedtime

topical steroids (eg fluorometholone) for short term use

Question 14

dry eye ophthalmologist management

Answer 14

• punctal plugs
• therapeutic CLs (scleral provides
  moisture and promotes healing)

Question 15

hordeolum vs chalazion location

Answer 15

hordeolum is found at or near lash follicle whereas chalazion found above lashes on upper lid

Question 16

hordeolum vs chalazion causes

Answer 16

hordeolum is caused by bacterial infection either at root of lash follicle or in the oil gland of the lids

chalazion is caused by a blocked oil gland (Meibomian or Zeis)

Question 17

RGP FLUOROSILICONE ACRYLATE VS SILICONE ACRYLATE

Answer 17

addition of fluorine improves wettability, deposit resistance + oxygen permeability

fluorosilicone = very high dK, fewer deposits but brittle

silicone = low to med dK, good scratch resistance but attracts proteins