contact lens materials

Don't Compromise With Your Teenagers

BY KATHY DUMBLETON, MSC, MCOPTOM, FAAO, & LYNDON JONES, PHD, FCOPTOM, FAAO

Choosing an optimal contact lens for teenagers can be somewhat of a dilemma. Daily disposable (DD) lenses may appear to be the best choice because this modality offers increased convenience, fewer overall complications, fewer unscheduled visits and superior patient satisfaction. However, DD lenses have (until recently) been manufactured only in low-Dk/t traditional hydrogel materials, which may cause physiological compromise when worn for extended periods of time.

Younger wearers typically are less compliant than more "mature" wearers and, when wearing DDs, severe complications can still result. Many teenagers admit to frequently "napping" while wearing their lenses. A recent study has shown that even dozing for a period of one hour results in significantly greater corneal swelling while wearing traditional hydrogel lenses compared with silicone hydrogel lenses.

A New Option

Given the wearing habits of teenagers, a preferable lens material is arguably a silicone hydrogel, but a desirable modality remains that of daily disposability. Eyecare practitioners in parts of Europe are now able to combine these two features with the recent release of the first DD silicone hydrogel contact lens, 1-Day Acuvue TruEye (Johnson & Johnson Vision Care) (Table 1). The lens is made from narafilcon A, a new material that features a new form of the proprietary Hydraclear technology specifically designed for the DD modality. The lens incorporates polyvinyl pyrrolidone (PVP) throughout the lens matrix to act as both a moisturizing and a wetting agent. With a Dk/t value of 118, this lens may be the preferred choice for many patients, particularly when compared with other currently available DD lenses.

A further advantage of this lens for younger patients is the Class 1 UV protection offered by the material. It is particularly important to protect young wearers from long-term UV exposure.

Coming Soon

1-Day Acuvue TruEye will be available in North America later this year and will no doubt be rapidly followed by other DD silicone hydrogels. We will then be able to offer the health and convenience advantages of this new group of lenses to many patients including teenagers, for whom this modality may be an excellent choice. CLS

For references, please visit www.clspectrum.com/references.asp and click on document #159.

Dr. Dumbleton is a senior clinical scientist at the Centre for Contact Lens Research in Ontario, Canada. Dr. Jones is the associate director of the Centre for Contact Lens Research and a professor at the School of Optometry at the University of Waterloo, Ontario, Canada. He has received research funding from Alcon, AMO, B&L, CIBA Vision, CooperVision, Johnson & Johnson and Menicon.