Alden HP Prosthetic

 
  Materials Diameter Base Curve Sphere Cylinder Axis
ALDEN
HP TORIC
or
SPHERE
HP 49
(Hioxifilcon B)
ANY
AVAILABLE

14.5 suggested
ANY
AVAILABLE

8.3, 8.6, 8.9
suggested
+30.00 to
-30.00

in 0.25 steps
-0.25 to
-10.00

in 0.25 steps
1° to 180°
in 1° steps
ALDEN
CLASSIC SPHERE
CLASSIC 38
Polymacon,
38% water,
9Dk (IS0)
ANY
AVAILABLE

13.0, 13.5, 14.0 suggested
ANY
AVAILABLE

7.7, 7.9, 8.1, 8.3,
8.5, 8.7, 8.9 suggested
+30.00 to
-30.00

in 0.25 steps
-0.25 to
-10.00

in 0.25 steps
1° to 180°
in 1° steps

Empirical Fitting Guide

Diameter Selection

  • Use the 14.5 diameter for normal-sized corneas
  • If a different diameter is desired, add 3.5 mm to the HVID to calculate the lens diameter

Base Curve Selection

  • Use the chart to select the base curve based on the diameter and average K reading

Power Determination

  • Use standard vertex adjustment to convert the spectacle Rx, or call our consultants and let us do it for you

Adjustments (when necessary)

  • When evaluating the fit of the lens, please provide our consultants with the following data:
    • Fit/movement (base curve evaluation)
    • Lens overlap (diameter evaluation)
    • Orientation, in 1° increments if possible
    • Over-refraction
  • We’ll calculate the Rx for you
BASE CURVE SELECTION CHART