Clinical

Front 1

Based on the rule of thumb expectations for age related accommodative amplitude, at what age will each typical add power be needed

Front 2

at what add power do tri-focals become necessairy, and why

Back 2

+1.50 and above (assume you only use half of accommodative amplitue for prolonged periods)

Front 3

Where do you normally fit bi-focals and tri-focals

Back 3

Bifocal About 1 mm below limbal margin Trifocal Lower pupil margin – or a bit lower

Front 4

What are the 4 factors that seg inset depends on

Back 4

PD, viewing distance, vertex distance, lens power (do to prismatic effects)

Front 5

inset Seg inset Total inset

Back 5

Distance decentration or inset Frame GC to MRP location (lateral component) Seg inset MRP to segment center (OC) (lateral component) Total inset Frame GC to seg center (lateral component) Distance decentration + seg inset

Front 6

You will have a small amount of prism in PALs that is not part of the rx. This is normal and to be expected. It should be yoked BD and will be equal between the two eyes. This is due to prism thinning which creates uniform thickness through the lens

Back 6

None

Front 7

When selecting a frame for a PAL, what is the typical minimun fitting height and minimum area for distance viewing

Back 7

Minimum recommended fitting height varies with PAL design – range is 13-24 Minimum area above fitting cross – about 10 mm

Front 8

Where do you fit PALs

Back 8

with the fitting cross in the center of the pupil

Front 9

what is the most comfortable vertical viewing position

Back 9

15 degrees of depression (10-20 degrees is comfortable)

Front 10

What does selecting an appropriate base curve in a lens accomplish

Back 10

minimizes aberrations with peripheral viewing