Gas Perm Bifocal Fittings Don't Have To Be Hard!

At my practice, Dr. Steven Lutz and Associates in Ann Arbor, MI, a large portion of our patients are contact lens wearers. Many of the patients we fit with contact lenses are multifocal (bifocal) wearers. Most of these patients wear soft contact lenses, but about 15% are gas permeable (rigid) lens wearers, sometimes called RGP's.

Because gas permeable contact lenses are completely customized, and have multiple variables that need to be manipulated to get the correct prescription, they have a reputation of being much more difficult to fit than a soft multifocal lens. This does not always have to be the case. If a few fundamental concepts are kept in mind, gas permeable multifocal contact lens fittings can be relatively straightforward.

I put bifocal gas perm wearers in two categories: those that the contact lens will center on the eye and those that the contact lens wants to ride up higher ("superior attached fit").

Lifestyle Corporation makes a multifocal contact lens that is designed to ride up on the eye, tucked under the upper lid. This design is my first choice for patients where the lens wants to ride up.

Art Optical Corporation in Grand Rapids, MI makes the Renovations gas permeable multifocal contact lens. This design is my first choice for centered-fit patients.

There are often clues in the eyelid and eye architecture that helps the doctor determine if a centered-fit lens or high-riding lens will be preferable. If the patient's upper lid covers much of the superior cornea (the upper lid hangs down a bit), this is often a good indicator for a high riding lens design. Patients with upper and lower lids that are quite far apart (large aperture) are usually better candidates for a centered-fit design. Diagnostic contact lenses are the key - we always put diagnostic contact lenses on the eyes to ultimately determine which design works best for each individual patient.

If you are an RGP contact lens wearer, make certain that your optometrist specializes in RGP contact lens fittings, so your next fitting doesn't have to be "Hard"!

Steven Lutz, OD
Serving Ann Arbor, Saline, Ypsilanti, Pinckney, Milan, Dexter, Chelsea, Brighton, Howell, Whitmore Lake and surrounding areas since 1988.