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Just for some background, each category of lens implant has several options in part because there are different major producers competing in each of these spaces. I will describe the options on a categorical basis which I feel facilitates understanding key differences in patient options (let’s look at the forest and not go weed wacking).

Standard Monofocal Lens Implant:

Monofocal lens implants give the patient good distance vision (assuming there is no significant uncorrected astigmatism). The patient will need to use glasses for reading and intermediate distance tasks.

Enhanced Monofocal Lens Implant

There are a few different options here. The principal idea is the focal point range is broadened, which gives the patients a wider range of in focus vision. This that can include increased clarity of vision for intermediate distance tasks compared to pure monofocal lenses (e.g., viewing dashboard of car, eating food, computer work).¹ When combined with mini-monovision technique (in which the non-dominant eye receives a more near vision biased target), the range of vision can be extended.

Bottom line -> You will gain more functional intermediate vision with these options but should still expect to wear reading glasses for near tasks (e.g., reading your cell phone or the fine text on medication bottles).

Extended Depth of Focus Lens Implant

These lenses take advantage of a differential curvature profile of the lens surface to extend the focal point and provide a greater range of functional near vision. This is similar to the previous category but because these lenses provide more than the threshold of 0.6D of functional range of vision, these are considered “premium” lenses that insurance companies will not pay for (i.e., similar to LASIK refractive surgery, the cost now falls on the patient). Intermediate vision is the main advantage endowed by these lenses when compared to monofocal lenses (i.e., computer vision, reading one’s dashboard off the car while driving). Near vision in the 20/30 to 20/40 range is achievable with these lenses BUT this is not always the outcome and patients should still expect to use reading glasses for near vision tasks (e.g., reading a book, viewing one’s cell phone). Perhaps the best perk of these intraocular lens choices is that the patient has a better chance of avoiding the glare and halo effects that are more likely to accompany other types of premium multifocal lens implants. The optical quality and contrast sensitivity is another strength of these lenses.

Multifocal Intraocular Lens

Again there are numerous individual options in this category. The basic principal is that the optical system of the lens splits the light into 3-4 focal points to try and deliver clear vision at distance, intermediate, and near.

SATISFACTION->

• In one study that followed 27 patients, 88% of patients were fairly satisfied to very satisfied with one model of a multifocal lens implantation placed in both eyes.²
• In one study, 85% of patients were “Very satisfied” with a particular model of multifocal lens implant. 12% were “somewhat satisfied”.³

GLASSES INDEPENDENCE->

• In one study, just over 90% of patients were glasses free.⁴
• In another study, 83% of patients were completely glasses independent.³

POTENTIAL DOWNSIDES TO CONSIDER

• Halos, glare and starbursts are a consideration. One study found glare to be both frequent and severe in 2% of patients that received a particular multifocal intraocular lens.⁴ In the same study, 4% of patients reported frequent halo and 2% of patients characterized the halo as severe.
• A potential decrease in contrast sensitivity or the ability to perceive sharp outlines of small objects.⁵
• The possibility of lens exchange should be factored in. Studies have reported rates of multifocal intraocular lens exchange among dissatisfied patients ranging from 0.85% to 7%.^6,7

Toric Lens

All of the above lens implants can also be delivered in a toric mode to correct corneal astigmatism. Note that if a standard monofocal lens is converted to its toric form, it is then considered a premium lens with an associated out of pocket charge that will not be covered by insurance.

Simulators

Before undergoing cataract surgery, patients often find it very useful to view an online simulator (especially when a premium lens is being discussed). Below is a static image simulation that drives home the difference between the near vision typical of a monofocal lens vesus a multifocal lens. Please note that every patient will have a different experience after cataract surgery and the below images are not meant to serve as references for surgical outcomes.

Remember, even if you receive a monofocal lens implant, you can still obtain reading glasses to make your near vision clearer.

Disclosure: No one intraocular lens type or manufacturer is being promoted over another on this website. The above descriptions are intended to give patients background information about commonly used categories of lens implants. Lens technology continues to evolve and this website does not include information about every individual category or type of lens implant. Final selection of a lens implant is a decision made between a patient and their personal cataract surgeon. Any questions on how the above information might relate more specifically to your circumstances should be directed to your personal cataract surgeon.

References