For contact lens wearers, the onset of presbyopia in middle age may seem to mean your contact wearing days are numbered. But that may no longer be the case as contact lens companies expand their development of multifocal contact lenses specifically targeted at middle aged readers.
If you’re like me, reaching the mid-forties means the print in reading material seems to be getting smaller and focusing on close objects is not as easy as it used to be. This change in vision is due to the normal aging of the eye, called presbyopia. Many people who don’t otherwise need glasses chose to wear non-prescription readers to compensate for presbyopia. But for those who already need help with distance vision (nearsightedness) it may be time for bifocals. The good news for contact lens wearers is that there are new developments in multifocal contact lenses that allow better vision at multiple distances, from up close to far away.
If you are familiar with bifocal glasses, you know the lenses are designed with two distinct prescriptions – one for close vision and another for distance with a clear dividing line between them. Progressive lenses smooth this divider to provide better vision at intermediate distances.
Many different contact lens manufacturers offer either bifocal or multifocal soft contact lenses using principals similar to those in bifocal glasses.
• Bifocal contacts – These lenses typically use up to five concentric rings to alternate prescriptions for near vision and distance vision, with distance correction at the center of the lens.
• Multifocal contacts – These lenses correct near vision in the center of the lens, and gradually transition to distance vision in a ring at the outer edge of the lens.
• Dominant/Non-dominant – This method corrects the dominant eye for distance in the center of the lens with a smooth transition to close vision correction in the outer ring. The non-dominant eye reverses this, with close vision correction in the center of the lens and distance in the outer ring.
Manufacturers selling the Dominant/Non-dominant style of lens claim that these lens pairs can provide clearer vision correction than other styles because the center of the lens provides the largest field of vision on the lens. This type of correction requires the brain to choose which eye to primarily use for varying distances. Some people have no problem adapting to this, others adapt over time, and still others are not able to function with this type of correction.
Lens manufacturers also vary in their ability to make minor corrections using contact lenses. So in the early stages of presbyopia, one type of contact lens may be more appropriate while another type will work better when more correction is needed.
Other considerations in choosing contact lenses is which lenses work best for dry eyes, the ability of the lens to transfer oxygen to the tissue of the eye, and the function of the lens at night or in low light. Be sure to visit an eye doctor trained and experienced in fitting multifocal or bifocal contact lenses and ask about your options.
Sources:
WebMD
Presbyopia Contacts Website
Contact Lenses for Presbyopia Press Release