Hands On - ASK THE LABS
by Karlen McLean, ABOC, NCLC

PARKINSON'S PROBLEM

Q Can you make frame and lens style and material recommendations for a patient with Parkinson's disease? He has trouble putting on and removing his glasses and often pull frames out of shape, even with spring hinges.

A With Parkinson's, shakiness and coordination problems can cause eyewear misalignments or even breakage.

Our lab suggests styling your customer in frames with library-type temples, so the temples slip straight on and off. He should also be counseled to take his frames off by the bridge rather than by the temples to avoid bending temples outward. A plastic frame with a form-fit bridge would be better than a frame with nosepads, which can bend and break.

We'd also recommend poly or Trivex lenses for strength and safety.

-- Kathryn Gross-Edelman,
Pech Optical Corporation,
Sioux City, Iowa

AVOIDING DBL DEBACLE

Q Many frames today come in odd shapes and sizes. What's the best way to get accurate measurements to my lab?

A Frames are measured at our lab in one of four ways: 1. An entire frame is traced; 2. A pattern is traced; 3. A demo lens is traced; 4. A frame shape is recalled from a points file. Sometimes manual drawings are also sent in to us.

Frame tracers do a good job of handling most full-metal and plastic frames. The tracer creates a frame points file that is attached to the Rx information.

There are two situations that are problematic if not handled correctly. First, it's difficult for us to handle frames with circumferences (C sizes) less than 110mm. In that case, our tracers and edger blocking parts are larger than the lenses to be cut.

Second, all rimless styles require that the bridge (distance between lenses or DBL) measurement is manually entered rather than calculated. We use a pupillary distance (PD) ruler to measure the DBL.

Frequently, the actual DBL measurement is slightly larger or smaller than what is stamped on the frame or provided by the manufacturer. If an inaccurate rimless DBL is entered, the finished Rx often has a wide or narrow PD. So take care to provide accurate DBL measurements.

-- Sandy Morgan, Volunteer Optical, Knoxville, Tenn.

In the Doghouse

Q One of my patients is a professional dog walker. In summer her eyewear slips down, and in winter she complains that her eyewear gets cold and uncomfortable. She currently wears a metal frame with adjustable pads and standard temples with regular plastic lenses. What frame and lenses would you recommend?

A A sports-oriented frame or a lightweight rimless design could solve the problem. Especially if the individual is wearing a large frame, high-index, polycarbonate, or Trivex lens materials may solve part of the weight problem. Or try a lightweight plastic frame--they are less temperature sensitive and with the right fit should solve your dog walker's blues.

-- Ed Dietz, Dietz Laboratories, Fort Worth, Texas

If you have a question you'd like to have answered in Ask the Labs, send it to Karlen McLean. Fax: 215-643-1705. E-mail: mcleank@boucher1.com. An archive of past Ask the Labs columns can be found on the Eyecare Business Website at www.eyecarebusiness.com.