Choose the Right Lens Replacement for your Cataract Surgery

Once you decide to have your cataract surgery or lens replacement, the next big decision is to decide on the type of intraocular lens. Everyone that has cataract surgery needs a lens replacement and each one has to be fit for your eye and specific situation. The following flow sheet sums up my recommendations, but you can look below it for an extended discussion.

There is a risk and benefit assessment that must be performed for the different types of lens implants. If you have significant astigmatism that can be corrected with the lens implant, you should always have it corrected with a toric lens in my opinion. Astigmatism means the eye is shaped more like a football than a basketball; it blurs the vision at near and distance and there really is not a benefit as far as clarity of vision. I think there is no significant risk with using a toric intraocular lens. Astigmatism adds in distortion and unequal image magnification in glasses so I recommend toric lenses for people with significant astigmatism even if they do not mind wearing glasses afterwards. From experience, people with a lot of astigmatism postoperatively are frequently distressed by the quality of their vision. The lens can occasionally rotate, but it is rare and usually does not make the astigmatism any worse than it was before. There are toric lenses that allow you to see clearly without glasses at one distance, or at near and far.

If you want to see clear at distance and up close, you have to decide between a multifocal lens implant, extended depth of focus lens, and sometimes monovision. In my experience, monovision is usually not tolerated that well. It is best for people that used it and had success with monovision contact lenses. It often results in difficulty with depth perception, and there is usually a range of vision that is not clear depending on the correction. All the eggs are in one basket with each eye doing the bulk of the work for either near or far, so if either eye is a little off or changes a little with time, the range of vision can really drop. Monovision tends not to work nearly as well once you have cataract surgery because you lose focusing ability and even those who enjoyed monovision in the past often do not feel that it is as good after surgery. If I am going to perform monovision, I usually recommend that it is combined with an extended depth of focus lens so the range of vision is significantly increased.

An extended depth of focus lens is in between a monofocal lens (which focuses at one distance) and a multifocal lens which usually gives clear distance, intermediate and up close (as far close as 12 to 18 inches). As of the writing of this post, I use the PureSee lens for my extended depth of focus lens of choice. This lens lacks rings and this significantly reduces the risk of glare and halo at night. Also, the FDA did not find that this lens significantly reduced contrast sensitivity. The extended depth of focus lens usually provides great distance vision, and great intermediate vision. This lens would be good for seeing cars while driving, but also seeing your dash. It is usually good for seeing your computer or a table that is in your lap. It is not good for reading up close. It has a low risk of side effects, but you do not as much range of vision as a multifocal. Usually you would still need glasses to read books or look at smaller print. This is a great lens for people with mild eye problems, or for those who want as much glasses independence as possible, but want to minimize risk.

A multifocal lens implant usually lets you see at distance, intermediate and near. You will need good lighting to read, but most patients have little need for glasses. They will need help with prescription bottles and very small print or in poor lighting situations. There is usually some mild starbursts at night with driving. If nighttime driving is extremely important for you, then this might not be the right lens for you. This is also not a good lens if you have any abnormalities with your eyes because there is a slight decrease in the ability to distinguish contrast. However, this is the lens that is most likely going to get you completely out of glasses.

The last class of lens is the light adjustable lens. It is good at correcting your vision for near or far. It uses a blended form of vision to help you get out of glasses, but you will still usually need reading glasses. It is best for people that are hard to accurately correct their vision the first time with a lens implant such as those who have had LASIK or RK. There are some additional risks with the light adjustable lens and delayed visual recovery due to not being able to lock in the lens until about 6 to 10 weeks after surgery.