Baby boomers have never wanted to grow old gracefully. Thanks to advances in technology, bifocal and multifocal contact lenses are a viable option for the current generation of presbyopes. Patients in their middle years today take their health care into their own hands. They are more aware of the alternatives that are available for vision correction than the previous generations. Many want to maintain their youthful appearance as long as they can and want to be able to see and be seen without glasses. This market is ripe for multifocals since some may already have tried reading or bifocal glasses or monovision contact lenses and had difficulty adjusting to them.
Soft and RGP Options:
A number of design options exist for both soft and rigid lens (RGP) correction. All soft bifocal and multifocal designs are simultaneous vision lenses. That is, they permit light from both near and distance to enter the pupil at the same time. Patients must train their brains to select the desired image and filter out or ignore the unwanted rays of light. Some designs have the distance power in the center, others, the near. Some are progressive, gradually changing from distance to near or near to distance seamlessly, in a manner similar to multifocal glasses; others are concentric, and have either distance or near in the middle, surrounded by one or more rings that contain the correction for the opposite focal length.
Rigid bifocals and multifocals not only encompass the full range of simultaneous vision designs but are also available in alternating vision or translating designs. Alternating vision lenses are designed to move up as the patient looks down, allowing the near portion of the lens to enter the pupillary area and enabling the patient to read.
Alternating vision lenses may be concentric, usually with a central distance zone surrounded by a near ring, or they may resemble a bifocal or trifocal spectacle lens, with the reading segment in the lower portion of the lens and prism ballast added to weight the bottom of the lens and keep the near zone in a downward position. Some translating rigid bifocals and trifocals are truncated. Truncation involves removing a segment of plastic from the lower edge of the lens, leaving a straight bottom edge. This enables the lid to help push the near zone of the lens up to the pupil when the patient looks down to read.
Industry estimates indicate that only three percent of potential patients are currently wearing some form of presbyopic contact lens correction even though improved materials and designs continue to be introduced. You should visit your eye doctor to determine if bifocal contact lenses are a viable correction option.