Multifocal contact lenses are contact lenses that are designed to work similarly to a no-line bifocal in glasses. The multifocal contacts have two powers in the contact lens to correct for a distance power and a reading or near power. These lenses are a great option for anyone over forty who wants to continue wearing contact lenses and does not want to wear reading glasses over them.
Why a Multifocal is Needed
Multifocal contact is needed when the eye no longer is able to focus adequately at near.
This usually begins in the early to mid-forties and worsens with age. This is a normal aging change of the eye.
With age, the lens in the eye becomes less flexible and more resistant to movement.
The lens movement and flexing are what allow for focusing on things up close or within arm’s reach.
Once the lens is too rigid to flex and focus enough, reading glasses, bifocal glasses, or multifocal contact lenses are needed to provide clear vision when looking up close.
Design of Multifocal Contact Lenses
Multifocal contacts all follow one of two design systems: either a distance center with near surround power or a near center with distance surround power.
The majority of multifocal contact lenses utilize a near-center design because the pupil is naturally smaller when looking at a close object compared to when looking far off.
In a near-center multifocal contact, the center of the contact lens has the reading power and then in tight concentric circles, the distance power and reading power alternate around the center.
Currently, only one multifocal contact lens is available with a distance center design. This design is essentially the same principle as that of the bear center but begins with the distance power in the middle.
Problems with Multifocal Contacts
Multifocal contact lenses can be a great tool when worn successfully but these contact lenses can be difficult to fit and find the exact best option.
Since there are multiple powers in one contact lens, the vision may not be as crisp as that with glasses or single-vision contact lenses.
It can be difficult to get multifocal contact lenses that are strong enough in reading power without negatively impacting distance vision.
Symptoms of this can include blurry distance vision, trouble with driving at night, or excessive halos around lights.
Fixing Problems with Multifocal Contact Lenses
If there are problems with multifocal contact lenses, there are specific troubleshooting steps that are followed.
To improve distance vision, the reading add power may be reduced or the distance power may be increased.
If neither of those options resolves the distance blur, switching to a distance near design may be necessary.
Conversely, if the near vision is not adequate, the reading add power may be increased in one or both eyes or the distance power may be decreased.
If fitting a distance center design, a near center may also improve the near vision.