Multifocal contact lenses are a special type of contact lens that helps to correct distance, intermediate, and near vision. These types of contact lenses are needed in individuals with presbyopia – or if reading glasses are needed for near vision. Wearing multifocal contact lenses may not provide the best vision at distance or at near, but should provide excellent and functional vision at all distances. There may be some instances in which wearing reading glasses over the top of the contacts or wearing glasses with a bifocal may be a better fit than multifocal contact lenses. Fitting for a multifocal contact lens is more involved than that of a single-vision contact lens due to the additional powers that are included to provide clear near vision.
How Multifocal Contact Lenses Work
Understanding how multifocal contact lenses are able to provide clear distance, intermediate, and near vision is important to better understand the benefits and limitations of the lenses.
With presbyopia, the eye needs a different power of a prescription for seeing clearly in the distance than seeing clearly up close.
In glasses, these different prescriptions are provided using a bifocal or no-line bifocal which has the power for the distance at the top and the near at the bottom.
However, in multifocal contact lenses, both powers are found throughout the lens in concentric rings of alternating powers.
This allows the eye to have both powers at all distances and then utilize the power that makes the vision clear.
The brain will naturally adapt to see the clear image and not the blurred image and it will not require any active thought to select which power to use.
This design is great for those who have near tasks at unusual positions (plumber, carpenter, mechanic) or those who rapidly go between distance and near tasks.
However, this design does create a small amount of defocus at all distances. This is often so subtle that it is not noticed, but for the finest details, glasses may be a better choice.
How Multifocal Contact Lenses are Fit
A fitting for multifocal contact lenses will involve trialing distance and near powers to find the perfect sweet spot which provides excellent distance and near vision and minimizes perceived blurriness.
To do this, a trial lens is selected based on the distance refraction and near add that is needed for glasses.
With these lenses in, both the distance and near vision are tested and then compared with loose trial lenses to evaluate if more near power is required for better vision up close without sacrificing the precision of the distance vision.
After determining the proper power for the multifocal contact lenses, an eye doctor will dispense a trial pair or several pairs if the lenses are daily lenses.
Wearing the lenses in the real world is important prior to purchasing a year’s supply given the distinct differences between tests in an exam room and day-to-day life.
If you are satisfied with the vision from the contact lenses, then you may order the lenses as a supply.