Lens Fitting Guide

Toric soft lenses

Fitting Procedure

• Full refraction and eye examination
• Keratometry
• Initial lens selection
• Initial choice of power and axis should be closest to the spectacle prescription (allowing for vertex adjustment)

Assessment of Initial Trial Lens

• Place the lens on the patient’s eyes and allow to settle.
• Record the visual acuity
• Check the lens fit and note axis orientation* with slit lamp
(*Focus^® DAILIES^® TORIC with AquaComfort™ has no orientation markings)
Fitting criteria desired results:
– achieves acceptable visual acuity
– is comfortable on the eye
– a “Good fit” is demonstrated
– lens has stable orientation

A Flat Fit

• May give poor centration
• May give unstable vision
• Can cause discomfort
• May exhibit variable rotation
• Displays a rapid ‘push-up test’ response

A Steep Fit

• Does not move adequately
• Sluggish or resistant to ‘push-up test’ with lower lid
• May not orientate correctly
• Can cause blanching or nipping of limbal conjunctival vessels. This should be avoided as it can lead to corneal complications

A Tolerance Trial

• Of 20 minutes or more allows a more accurate reassessment of fit, orientation and comfort
• “Good fit” criteria should still apply

Over-Refract

• To determine the final sphere, cylinder and axis giving the optimum visual acuity
• Use the L.A.R.S. formula (Left Add Right Subtract) to compensate for any lens rotation