Q. Those Pesky Specs
What is the recommended procedure to clean lenses before they are backside coated? We get a lot of specks on polycarbonate that we are unable to completely remove. Please advise, even if we need to invest in new equipment.

-Craig Huston, King Optical, Winnepeg, Canadai

A. A Here's our recommended procedure: De-block lens, wash lens in soap and water with a fine sponge, keeping the sponge and lens submerged while washing. Rinse the lens in running water, and blow off dry using a clean air supply (not shop air). Lenses are now placed in job tray to go to coating. At backside coating, we recommend that a citrus degreaser is used diluted in water (such as a product called Knockdown sold by Grainger). The lens again is washed, but only on the backside, do not rinse it or dry it. Place directly into the coater.

-Norm Vallee, Essilor Of America

Q. To Believe... or Not? 
For years, dispensers have been verifying multifocals by measuring the back vertex power. Then PALs came along, with the add power conveniently engraved on the lens. Still, all the technical information out there recommends manually measuring the add power. Is there any reason to not accept the engraved add power as being true?

-Andy Winters, ABOM, COA

A. I recently taught students at Southern California College of Optometry on progressive addition lenses. We encourage them to verify the add power in order to become accustomed to the procedure, but I suggested when they can find the add power marked on the lens, that will be the correct add power. I've never found an add power mis-marked on a PAL. I do point out that sometimes markings can't be found or have been covered by a coating. For that reason, they need to be able to determine add power the conventional way.

-Carol Farnham

A. Here's a suggested format for the Patient Rejection Form which is part of the OLA's Duty to Warn Kit. Bear in mind that Pamela Miller (O.D. and attorney), popular lecturer on Duty to Warn, feels these do not fully protect the doctor (they can always say "I didn't know what I was signing"). Nevertheless, it certainly does impress the patient about how strongly the doctor feels about the subject.

Patient Rejection Form
I understand that my doctor/dispenser has recommended polycarbonate lenses for my visual safety and protection. I hereby acknowledge that I have voluntarily, and with full knowledge of the possible consequences of my selection, decided to utilize an alternative material for my eyewear. I am ordering lenses made of ____ CR39 ____ Glass ____ High Index plastic. Poly lenses were recommended for the following reason(s): ____________

Leave room for the patient to sign and date it. There should also be a line where a parent or guardian can sign, if that's appropriate. Finally, there should be a line for a witness to sign (the doctor or dispenser). Most OLA labs can supply the OLA Duty to Warn Kit, which includes a copy of this form. EB

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