prescribing for presbyopia
A New Text for Fitting Presbyopes with GP Lenses
BY CRAIG W. NORMAN, FCLSA
There are many articles related to the use of contact lenses for correcting presbyopic patients, quite a few of which have appeared in this publication. Such articles most often review a particular topic or recap a clinical study. There are also some great books in print that cover the general topic of contact lenses and include chapters on presbyopic contact lenses.
To the best of my knowledge, there hasn't been a specific textbook that focuses strictly on any category of contact lens and presbyopia — until now.
A New Resource
The Centre for Contact Lens Research (CCLR), School of Optometry at the University of Waterloo, Ontario, Canada has developed the 88-page "Correction of Presbyopia with GP Contact Lenses" (Figure 1), a new publication that focuses on multifocal and bifocal GP lens designs, their fitting and how to incorporate them into eyecare practice.
Step-by step fitting and evaluation procedures for the different design concepts are described in detail. Accompanying these sections are beautiful photos, illustrations and graphics that depict the various lens-to-cornea fitting relationships.
Sprinkled throughout the text are tips from fitting experts from across the globe. It also features a very nice FAQ section that will help practitioners and staff alike.
The text describes in detail opportunities that exist for presbyopic GPs, with an excellent comparison of the differences in today's GP multifocals from those of the past.
Figure 1. This new text facilitates fitting presbyopes with GP lenses.
An interesting feature of the book is how the authors succeed in reducing much of the confusion regarding the myriad of presbyopic GP designs by classifying them into only two categories.
They refer to lenses that rotate under the influence of the blink yet still provide constant optical power for both distance and near as rotational designs. Examples include aspheric multifocals and concentric designs.
Designs that allow the eye to move independently from the lens, positioning either the distance or reading zone in front of the pupil at the proper time and are ballasted to stay in that position, are termed non-rotational. Bifocal designs that have distinct upper and lower zones and are weighted inferiorly fall into this category.
Don't Miss It
I'd like to be one of the first to publicly compliment the CCLR on its book. I had the opportunity to be one of its many reviewers, and I believe it will be extremely useful for many eyecare practitioners — from students to those more experienced in presbyopic patient management. It's informative, easy-to-read and well-organized from beginning to end.
"Correction of Presbyopia with GP Contact Lenses" was funded by a grant from Bausch & Lomb Inc., and is available free of charge from Authorized Boston Laboratories in North America. Foreign language versions will be available later this year. CLS
Craig Norman is director of the Contact Lens Section at the South Bend Clinic in South Bend, Indiana. He is a fellow of the Contact Lens Society of America and is an advisor to the GP Lens Institute. He is also a consultant to B&L.