Fitting Lenses

February 2018 Lenses

Improve Pal Success With Improved Pal Fitting

Parts 1 through 4 of this series described the importance of determining the visual axis measurement to maximize patient visual comfort and satisfaction with PALs. This final installment introduces methods and devices to obtain that measurement.
January 2018 Fitting Lenses

Improve PAL Success with Improved PAL Fitting

Part 3 discussed the effect of angle Kappa on PAL fitting. Part 4 addresses the effect of the dominant eye and alignment error on PAL success. A patient’s adaptive response is for the dominant eye to center on the clearest portion of the segment in the lens in front of the dominant eye. If the lenses are incorrectly aligned, the non-dominant eye’s visual axis will now fall outside the umbilic. That results in a head or eye turn to make near vision clear.
November 2015 Fitting Lenses

The Real Details of Vertex, Tilt and Wrap, Part Three of Three

With many variables to sort through in investigating a vision complaint, anything that could help to reduce the pool of possible suspects should be welcomed with open arms.
November 2015 Fitting Lenses

The Real Details of Vertex, Tilt and Wrap, Part Two of Three

Ask just about any eye care professional when knowing the fitting vertex distance of a pair of glasses is important, and they'll no doubt respond: "For powers over 6 diopters, you'll have to compensate the power for the difference between the exam vertex distance and the wearing vertex distance."​

October 2015 Fitting Lenses

The Real Details of Vertex, Tilt and Wrap, Part One of Three

For most of the last century, eyeglasses were fabricated using a binocular measurement for pupillary distance, and simply dividing it in half to center the lenses for each eye. This method delivered apparently great patient satisfaction, as visual complaints were not clearly traceable to the lack of using a "proper" monocular PD....even for segmented multifocals.
April 2014 Fitting Lenses

PD's and The Very Young

The very young can be quite difficult when taking a pupillary distance measurement.
September 2013 Fitting Lenses

Why Are Tilt and Wrap Important?

If you wear prescription glasses, you know that changing the tilt of the lens changes the effective power of the lenses—they "see" differently.
May 2013 Fitting Lenses

Position of Wear

POW or "position of wear" is a term that is used to describe the way that an eyeglass frame positions lenses in front of the eye.
December 2012 Fitting Lenses

Still Using A Ruler?

Are you using a millimeter ruler for PDs and fitting heights; does it define your expertise?
November 2012 Fitting Lenses

Clinical Tips

Clinical Tip When fitting multifocals, especially in higher powered Rxs, although you normally place the MRPs or optical centers at unequal decentrations to agree with unequal monocular pd's, you may wish to equalize the decentration of the segs for a better cosmetic result.