Lec 1 Prefitting Considerations

Question 1

What’s full time and part time wear for Cl

Answer 1

Full time is 5-7 days per week

Part time is occasional wear or few times per week

Question 2

What’s daily wear and extended wear

Answer 2

Daily wear is wearing during awake hours only

Extended wear is wearing CL continuously including overnight

Question 3

Advantages of a CL

Answer 3

Sports peripheral views

Glasses inconvenient

Cosmetics

Optical benefit with decreased vertex distance aniseikonia

Question 4

What’s a conventional CL

Answer 4

Replaced annually

Question 5

What’s a spherical RGP good for

Answer 5

Fitting near spherical corneas and where most of the astig comes from the cornea

Question 6

What’s a spherical soft CL good for

Answer 6

Fitting on most corneas with low astig

Question 7

Size difference between SCL and rigid

Answer 7

Rigid stays inside limbus and small but soft goes further out

Question 8

What’s a front toric RGP good for

Answer 8

Fitting on near spherical corneas where astig is from lens and there’s a lot

Question 9

What’s a toric soft CL good for

Answer 9

Fitting on most corneas (soft=drapes over everything) and can fix both lens and corneal…? Idk

Question 10

What are Bitoric or back toric RGP good for

Answer 10

Fitting on highly astigmatic corneas

Question 11

What are multifocal or bifocal CL good for

Answer 11

For patients requiring an add (both RGP and SCL)

Question 12

How to vertex back to get a CL power

Answer 12

Fcl = Fspec/(1-dFspec)

Question 13

If you move any lens (positive or negative) further away from the eye, what’s the prescription?

Answer 13

More minus as moving further away increases BVD so increases plus power so the prescription to correct is more minus

Question 14

What’s Delta K

Answer 14

Flat axis - steep axis @flat axis