Up to quite recently, the only option was to implant a monofocal lens which provides excellent vision after cataract surgery-but only at one set distance-usually predetermined for seeing things at a distance. Therefore, monofocal lenses will allow clear vision when at the movies or driving.

The downside to monofocal lens implants is that glasses will most likely be required for any type of near vision like reading, sewing or keeping your golf score.

In general, patients who choose to have monofocal lens implants will be dependent on glasses either some or most of the time in about 70% of cases. Patients who choose to have multifocal lens implants will only be dependent on glasses either some or most of the time in about 15% of cases. So, patients choosing multifocal lens implants typically experience greater overall freedom from glasses allowing them to participate in most everyday activities without dependence on, or the hassle of glasses.

While the goal of multifocal lens is to decrease a patient's dependence upon eyeglasses, there are some tradeoffs with the lens. The design and technology utilized by these lenses will create some degree of haloes around lights at nighttime. This halo effect is not problematic during the daytime because of the smaller size of everyone's pupil in daylight. The more the patient's pupil normally dilates in the dark, the more evident this phenomenon will be at nighttime.

Fortunately, this is more of a distraction rather than something that interferes with vision, and the human brain is excellent at adapting to such images over time. The overwhelming majority of patients are able to get used to this, such that it becomes much less bothersome or noticeable over time. Having the multifocal lens in both eyes seems to facilitate this process of adaptation. However, like many other visual symptoms, some individuals have more difficulty adapting than others do.

The multifocal lens is not an appropriate option for many patients. Reducing the frequency of wearing glasses is not a priority for everyone, and the individual patient's lifestyle and activities should be considered. For various reasons, the multifocal lens will not work as well in certain eyes. This is generally true if there are other ocular health problems, poorer visual potential, small pupils, and significant astigmatism.

Both multifocal and standard monofocal lens can provide excellent vision following cataract surgery. If the surgeon identifies a patient to be a good candidate for the multifocal IOL, then this is an option to consider if one wishes to try to reduce their dependence on glasses.