5.1.1 fits+orders

Question 1

Name 2 soft daily lenses

Answer 1

1) EV linarial ( MyDay/coopervision)
8.4/14.2
shy yes
DK/t 100
54% water content
UV yes

2) EV mere ( clarity 1day/coopervision)
8.6/14.1
shy yes
DK/t 86
56% water content
uv yes

Question 2

name 2 soft monthlies

Answer 2

1) ev opteye ( extended wear too/ bionifinty/coopervision)
8.6/14.0
shy yes
DK/t 160
h20 content 48%
uv no

2) EV lacrima plus ( clariti elite/bionifinty/coopervision)
8.6/14.2
sihy yes
Dk/t 86
h20 content 56%
uv yes

Question 3

soft lens designs / material available

Question 4

how do you adjust the fit of the lens

Answer 4

flat - steepen fit by reducing bozr/increasing td
step- flatten fit by increasing bozr/reducing td

Answer 5

TD= HVID+2
BOZR = 0.6-1mm flatter than average k reading
correct for change in vertex distance if spec rx >-3.50D

Question 6

Contraindications to cl wearing

Answer 6

1) active eye disease or inflammation
2) meds contraindicated to sol/cl e.g. beta blockers
3) allergy
4) inability to adhere to lens care ( age/diability/illness)
5) Unable to insert or remove
6) history of non compliance
7) mod-sever dry eyes( chronic blepharitis)
8) health conditions dm ( refractive error unstable //dm also increases MK risk )
9) ptergium obstructing lens from fitting

Question 7

reusable 2 weekly soft lens

Answer 7

reusable spa acute oasis
reusable toris- acute oasis for astigmatism

Question 8

wettablity

Answer 8

how easily the tear layer spreads across the lens surface

good wettablity - could coverage of tear film/good comfort /good vision

poor - lots of dry areas on surface

Question 9

surface lubricity

Answer 9

surface friction with upper lid

less friction- high lubricity - high comfort

Question 10

modulus

Answer 10

flexibility of lens
high modulus tough stiff lens
low modulussoft lens - drapes over ey more comfort

modulus depend on material /td /thickness

Question 11

water content

Answer 11

water absorbing power of lens/given as percentage

Question 12

oxygen permeability

Answer 12

how much oxygen is reaching the cornea

Answer 13

• low dk- hypoxic change to cornea
• v goot wettability - v good comfort

Question 14

1st gen sihy

Answer 14

• high dk/t - less hypoxic corneal complications
• high modulus tough material - mechanical complications
  poor wettability low wc

Question 15

new gen sihy

Answer 15

high dk/t
lower modulus than 1st gen - less mechanical complications

increased wettablity and wc compared to first gen- more comfortable

Question 16

where does the dk value apply

Answer 16

lens cente
so peripheral will have lower value

Question 17

dk value to prevent corneal oedema for daily wear

Answer 17

35 dk/t no less

Question 18

dk value to prevent corneal oedema for overnight wear

Answer 18

125 dk/t

Question 19

what are the advantages of shy

Answer 19

higher dk- fewer hypoxic complications such as corneal swelling/vascular changes
longer WT

Question 20

how does a high rx affect cl material

Answer 20

higher rx - thicker lens- less oxygen reaching cornea - so high dk/t lens chosen

> 6
lens may be uncomfortable so need to be wettable too

Question 21

what do dry eye px prefer for CL

Answer 21

lwc hydrogel more wettable than sihy

Question 22

first clinical sign of hypoxia

Answer 22

1) limbal hyperamia - so increase dk/t