Presbyopia and Multifocal Lenses
Presbyopia is a common age-related condition caused by the natural process of aging and typically affects people over 40.
It causes people to hold reading materials at arm's length and have difficulty with other close-up tasks. Reading glasses can correct these issues, but sometimes people with presbyopia must also wear prescription glasses. This means switching between two pairs of glasses as needed.
Bifocal and multifocal contact lenses offer a convenient alternative to reading glasses and eliminate the need for carrying two pairs of glasses by providing clear vision at all distances.
The Difference Between Bifocal and Multifocal Lenses
Bifocal lenses feature two distinct segments for different vision powers, providing clear focus for both near and distance vision.
In contrast, multifocal lenses include various lens types, such as bifocals, trifocals, and progressives. This means they offer multiple powers for versatile vision.
Multifocal contact lenses come in two designs: simultaneous vision lenses, which allow clear vision for different distances, and alternating vision lenses, which enable smooth transitions between distances.
Simultaneous vision lenses
Simultaneous vision lenses are a popular choice for multifocal contact lenses. They offer both distance and near vision zones on the lens simultaneously. Your eyes learn to focus on the desired object and ignore the other zone.
Two designs of simultaneous vision lenses: concentric ring design and aspheric design.
- Concentric ring design: Circular central area with a ring of alternate power. Rings can be adjusted for near or distance vision and additional rings for intermediate vision.
- Aspheric design: Blends multiple lens powers across the surface and center of the lens. Both distance and near vision power are located in the central visual area, and your eyes adapt to focus on the needed area for clear vision.
Translating or Alternating Vision lenses
Multifocal contact lenses, similar to bifocal eyeglass lenses, have distinct zones for different vision needs. The top of the lens is typically for distance vision, while the bottom area is for near vision. The added benefit is that this can be customized based on individual requirements.
Translating lenses use a thicker area or flatten the bottom to align with the lower lid to prevent the lens from moving in the eye. They’re designed for rigid gas-permeable materials, providing excellent visual clarity and allowing oxygen to pass through to the eye.
An Alternative Option to Multifocal Contact Lenses: Monovision
If you're having trouble adjusting to multifocal lenses, monovision lenses can be an alternative for your presbyopia. They use your dominant eye for distance vision and your non-dominant eye for near vision.
You can opt for single vision lenses in both eyes or use a multifocal lens in one eye for intermediate and near vision, known as modified monovision.
Your eye doctor will conduct tests to determine the most suitable lens type for each eye, ensuring optimal vision.
Are Contact Lenses Right for You?
Consider contact lenses as a convenient choice for managing presbyopia. Schedule a consultation with us today!