Polishing GP Lenses for Patient Comfort
BY JOHN MARK JACKSON, OD, MS, FAAO
Two great characteristics of GP lenses are their durability and their deposit resistance. Assuming that no prescription change is needed, a pair of GP lenses, with some basic maintenance, can last for several years.
Lens polishing is one piece of GP maintenance that you can perform in your office. While GP lenses resist deposits, they still need a professional-grade cleaning every so often. I tell patients to compare it to dental care: no matter how thorough you are when cleaning your teeth, you still need professional cleanings.
Polishing can also remove light surface scratches.
How to Polish GP Lenses
You need three things to polish GP lenses: a polishing unit, polish, and a lens spinner. The spinner tool helps you achieve even results and prevents damage to the lens optics as you polish.
Polishing the Front Surface Attach the lens to the spinner tool with the back of the lens against the suction cup. Apply polish to the flat sponge tool, and lightly touch the lens to the midperiphery of the sponge, allowing the tool to spin freely (Figure 1). Start with the spinner perpendicular to the sponge, then tilt the spinner so that it is at about a 60° angle to the surface. Go gently back and forth, changing the angle, while the lens spins. Keep adding polish as needed. After about 15 to 30 seconds, check the lens surface. Repeat as needed until the surface is clean and scratch-free.
Figure 1. Polishing the front surface.
Polishing the Back Surface Now attach the lens so that the front surface is against the suction cup. Use the cone-shaped sponge, and this time hold the tool so that the lens can’t spin. Touch the lens to the tip of the cone, and gently press into the sponge until the entire back surface touches the sponge (Figure 2). Hold it for a few seconds, then take the lens away from the sponge. Repeat for about 10 cycles. Check the lens surface, and repeat as needed.
Figure 2. Polishing the back surface.
Polishing the Edge This is easier with the front of the lens against the suction cup. Use the flat sponge. Allow the lens to spin, and hold the spinner nearly parallel to the sponge surface, so that the edge of the lens touches the sponge (Figure 3). Move the spinner in a straight line across the midperiphery of the sponge. Moving the tool like this varies the way the sponge contacts the edge, allowing for a smooth polishing action.
Figure 3. Polishing the edge.
See It in Action
Dr. Jackson is a professor at Southern College of Optometry, where he works in the Advanced Contact Lens Service, teaches courses in contact lenses, and performs clinical research. You can reach him at email@example.com.