Bifocal Contact Lenses Correct Astigmatism and Presbyopia
Some people with astigmatism who have had their refraction error corrected with contact lenses find that as they get older they have to use a pair of reading glasses overtop their contact lenses to read or do close-up work.
While that might not be such a big inconvenience there is a different option. There are astigmatic corrective contact lenses that can do both—correct your astigmatism and provide a reading boost for close work. The lenses are available in both a bifocal and multifocal design and several brands are available.
A visit to your eye care practitioner will enable you to determine whether you are a good candidate for these types of lenses and which brand is the best choice for you.
How do Contact Lenses Correct Astigmatism?
Having astigmatism means that either the lenses or the corneas of your eyes are irregularly shaped. The curves are mismatched. The curve in one direction is steeper than the curve in the opposite direction. Eyes with this type of irregular shape don’t bend light the same on each side. A toric contact lens has two different curves instead of one to correct vision at each curve.
When people who are wearing contact lenses blink, the blinking slightly rotates the contact lenses. The rotating of regular contact lenses won’t cause any issues because they are designed with the same curvature all around the lenses. But it will make a significant difference for people with astigmatism. So that the toric lenses stay in the correct positions on the curves they are designed to correct, the lenses are usually weighted at the bottom so that they don’t rotate during blinking.
Bifocal and Multifocal Astigmatic Contact Lenses
Some bifocal contacts for astigmatism are comparable in design to progressive eyeglass lenses. The refractive power gradually changes from the top to the bottom of the contacts. Others have concentric rings and the center of the ring either has the near-vision correction or the distance-vision correction.
Hybrid Bifocal Contacts
Hybrid bifocal lenses only work for corneal astigmatisms and they combine both rigid gas permeable material with soft lens material. The central portion is made of the rigid gas permeable material and that is surrounded by an outer ring made of soft contact lens material.
This design using the rigid gas permeable in the center portion works well for people with high amounts of astigmatism and those with keratoconus. However, because the center of the lens is hard, it is sometimes not comfortable enough for some people.
Cost and Other Considerations
Because of the complexity of designing astigmatic bifocal contacts and then the time it takes to get them fitted properly, the cost will be higher than for regular contact lenses.
Some people may still need to wear reading glasses for very small print or extremely detailed close-up work.
If you would like to make an appointment, call us 609.877.2800 or EMail us.
Gregory Scimeca, M.D.
Ophthalmologist and Medical Director
The Eye Professionals