CLs

Question 1

Explain SAM/FAP

Answer 1

-Steeper add minus. If the lens is too steep, add minus.

-Flatter add plus. If the lens is too flat, add plus.

Question 2

Explain WTR vs ATR astigmatism

Answer 2

-With the rule. Cornea is steeper in the vertical meridian.

-Against the rule. Cornea is steeper in the horizontal meridian.

Question 3

What Is the average curvature of the cornea

Answer 3

43.00 D

Question 4

How much base curve of a GP lens is equivalent to 0.50D

Answer 4

0.10mm

Question 5

Which Base curve is steeper 7.80mm or 8.00mm?

Answer 5

7.80mm (the lower the mm measurement, the steeper the lens is.)

-Picture a piece of string that is that length, and what kind of circle that string would create if drawn around a central point.

Question 6

When Prescriptions need to be vertexed for contact lenses, is the vertexing done before or after the equation?

Answer 6

Before

Question 7

What Are available cylinders for toric lenses?

Answer 7

Starting at -0.75, increasing in -0.50 increments
-0.75,-1.25,-1.75,-2.25 etc

Question 8

What Is the equation for finding vertex?

Answer 8

F2=(F1)/(1-x(F1))
Where:
F2: new dioptric value
F1: current dioptric value
x: change in vertex IN METERS (will be something like 0.012 for 12mm)

Question 9

Characteristics Of parallelepiped illumination (slit width, magnification, angle, purpose)

Answer 9

-1-2mm
-10x-25x
-30-50 degrees
-Scanning tissues directly to assess the tear film, cornea, lens anterior chamber. May also use indirect illumination to view adjacent tissues.

Question 10

Characteristics Specular reflection, illumination. (Slit width, magnification, angle, purpose)

Answer 10

-1-2mm (parallelpiped)
-10x-40x
-Same angle as light reflection
-Highlighting imperfections on surface structures, observe tear film, estimate tear meniscus, assess corneal endothelium

Question 11

Characteristics of retro illumination from the iris (light, slit, angle, magnification)

Answer 11

Light: med-high
Width: 1.5-2mm
Angle: 30-50 degrees
Mag: 16x-40x

Question 12

Characteristics Of sclerotic scatter (light, slit, angle, mag, purpose)

Answer 12

-Light: high
-slit: 1-2mm
-angle: 40-60 degrees
-mag: 6x-10x
-purpose: Uses the cornea to conduct light to provide an overview of corneal pathologies.

Question 13

Characteristics Of conical Beam (light, angle, mag,

Question 14

What amount of astigmatism can be corrected by tear lens?

Answer 14

-2.50

Question 15

Equation for vertical imbalance

Answer 15

P=(dxD)/10

Question 16

Minimum blank size equation

Answer 16

MBS=ED+2(decentration)+2mm