SCL Fitting Flashcards
1
Q
Steps in selecting a Lens
A
- Decision on modality
- O2 and water content considerations
- Decision on material
- Choose starting lens
- Look at available Rx and cost
- Manufactures guide for fitting
2
Q
Modality of wear considerations
A
Occasional (3 hours, 2/7)
- dailies
Work (9 hours, 5/7)
- monthlies
Full time wear at work, but non compliance
- dailies
Full time (16 hours, 6/7)
- fortnightly or monthlies
Slit lamp exam
- hypoxia
- previous pathology
3
Q
O2 and water content considerations
A
Water content
- if lenses drying up, increasing water content draws out water
Oxygen
- increased WT = Increased O2 transmission
4
Q
Decision on material
A
- hydrogel or silicone hydrogel
- Rx range
- cost
5
Q
How to figure out BOZR
A
- flattest K x 1.1
- fit slightly flatter than flattest k
6
Q
How to adjust Rx for BOZR
A
- K=F/(1-dF)
F= Rx
d= BVD in metres
7
Q
When to use a toric lens?
A
If cyl is >1.00
8
Q
Steps for inserting a SCL
A
- Px has head against the chair, Px looks up/down
- lower bottom lid, and Px looks away
- place lens onto conj,keep holding lids, Px looks left/right/up/down
- massage top lid if air bubbles
9
Q
How do you remove a SCL
A
- same eye lid control
- Px looks away
- slide SCL off cornea
- pinch off the conj
- perform health check
10
Q
What to record on record card for fitting
A
- coverage
- centration
- movement on blink
- comfort
- lag
- sag
- push up
- tightness
11
Q
Why does lens need to fit well
A
- comfort
- corneal coverage
- good centration
- movement on blink
- optimal tightness
- stable vision
12
Q
Characteristics of a steep fit
A
- minimal lens movement
- reduced limbal crossing
- conjunctival identification
- conjunctival redness
- vision improves immediately post blink
13
Q
Characteristics of a flat fit
A
- increased movement
- buckling at lens edge
- poor centration
- variable vision
- lens awareness
