CL Prescribing for Presbyopia
CooperVision's Proclear Multifocal lens appeases
CHOU, O.D., F.A.A.O.
I'm not usually excited by new contact lens technology because I've seen a number fail to deliver what I expected, let alone what the patient expected. To me, "new" means unproven, until it's withstood the test of time. With that said, I'm optimistic about the new Proclear Multifocal lens by
The Proclear Multifocal harmonizes two proven technologies: The omafilcon material in Proclear Compatibles, and the lens design of Frequency 55
Multifocal. I had the privilege of evaluating the Proclear Multifocal one year ago as a clinical investigator.
The patients' pronouncement
The clinical evaluation of the Proclear Multifocal included 62 eyes from 32 patients already wearing the Frequency 55
Multifocal. Four optometric practices participated in the study, including my own. When asked about the overall comfort of the Proclear Multifocal to the methafilcon equivalent, 40% of patient responses indicated better comfort, 49% the same and 11% worse. (This parallels my own experience.) Also, some 88% of responses indicated that the Proclear Multifocal was equivalent to, if not better than, the Frequency 55 Multifocal for vision, while 92% reported the same for handling.
CooperVision's Proclear Multifocal resists protein
Omafilcon is an exquisitely comfortable contact lens material. Made with phosphorylcholine (PC), a substance found in human cell membranes, PC technology is also present in other biomedical devices including coronary stents and ear implants. PC is a biocompatible and an electrically neutral molecule with a high affinity for binding water. Because it resists protein and bacterial adhesion, omafilcon is well suited for contact lenses.
The Proclear Multifocal shares the same design as the Frequency 55
Multifocal. Lenses are available in two "flavors:" the "D" lens (dominant eye) and the "N" lens
(nondominant eye). The "D" lens features a central zone of distance optics with a surrounding aspheric annulus with a progressive increase in add toward the periphery. The "N" lens design is the other way around: A central spherical near zone and a surrounding aspheric annulus with a progressive decrease in add toward the periphery.
The resulting optical effect is what CooperVision terms Balanced Progressive Technology, in which both eyes receive multifocal optics in a manner that leverages eye dominancy. This differs from modified
monovision, where the dominant eye gets unifocal distance vision and the nondominant eye receives multifocal near vision. Each "D" and "N" design is available in lens powers from +4.00 to 6.00 in 0.25D steps and four different add powers of (+1.00, +1.50, +2.00 and +2.50).
This allows for substantial optical flexibility and prescribing creativity. For example, you can prescribe "D" lenses for both eyes for the emerging presbyope who's unwilling to sacrifice distance acuity. To assist doctors in prescribing its multifocal lenses, CooperVision offers its complimentary MultiTrack software available for Palm hand-held devices.
With dry eye symptoms all too common among
presbyopes, practitioners now have the Proclear Multifocal for taming contact lens discomfort. The Proclear Multifocal raises the bar for soft multifocal lenses through a combination of comfort and visual quality. Try it. I think you'll find it exceptional.
DR. CHOU IS A PARTNER AT CARMEL MOUNTAIN VISION CARE IN SAN DIEGO, A CLINICAL STUDY SITE FOR VISION CORRECTION TECHNOLOGY. CONTACT HIM AT FAX (858) 484-9143.
Optometric Management, Issue: September 2004