Cataract surgery is one of the most common intraocular surgeries performed today.  The eye’s clouded lens is replaced by an artificial one made of various materials.  Replacing the intraocular lens has been around for more than 50 years but it became the norm during the 1980s. Prior to this people had to wear very thick glasses or contact lenses to make up for the lost power of the natural lens.

Today Cataract surgery has a very high success rate and few, if any complications.  The healing times are quicker and the results are better than ever before.

Just like the myriad of choices available for glasses and contacts, there are now many options available for the replacement intraocular lens.  In the past the surgeon made the best choice of lens for a patient and they had little input.  Today doctors often offer options for the intraocular lens.

We will break down the choices currently available for cataract surgery:

Standard IOLs

A standard IOL will replace the clouded lens of the eye with a lens that is designed to correct vision for one distance (distance or near).  This will still leave you needing to wear glasses or contacts to see at other distances that your new IOL doesn’t correct for.

The benefit of a standard IOL is that they are often fully covered by Medicare.  Any type of premium lens, like those that correct for astigmatism, are multifocal or are of premium materials will require you to pay the difference in cost out of pocket.

Toric IOLs

A toric IOL is designed to correct astigmatism just like wearing a toric contact lens.  Toric IOLs are considered a premium option and often have additional costs associated with them.

They can correct a moderate amount of astigmatism (generally from 1.00 to 3.00 D).  Many cataract surgeons will also employ astigmatic keratotomy (AK) or limbal relaxing incisions (LRI) to correct astigmatism by making small incisions in strategic spots on the cornea.

Placement of the IOL is critical with a toric IOL because the orientation of the lens must be just right.  If the lens rotates, it may be necessary to have another surgery to correct the movement of the lens or to replace it.

Aspheric IOLs

The curvature of a normal IOL is uniform.  An aspheric IOL has a flatter curve near the edge.  This helps reduce aberrations, most notably spherical aberration.

There has been some evidence that an aspheric IOL can help improve contrast sensitivity more than a standard IOL.  Although any IOL will provide clearer vision and better contrast sensitivity than the clouded one that is being replaced, ultimately the ability to perceive contrast comes down to the health of the retina, and more specifically the ganglion cells.

Companies like Bausch & Lomb, as well as Alcon currently have aspheric IOLs available.

Monovision With IOLs

This type of IOL really isn’t a specific type in itself.  It involves having one eye with and IOL designed for distance vision and the other eye with an IOL for near vision.  It is the exact same thing that happens when a patient is put in monovision contact lenses.

It is very important to know if you can adapt to, and are comfortable with monovision before having this type of cataract surgery.  Most people who pursue this already know they like monovision and wear monovision contacts.  If you are considering having this procedure, ask your doctor to let you try out monovision by wearing contacts first.  A common drawback to monovision is that depth perception and binocularity (two eyes working together) can be thrown off.  Anything at an intermediate distance such as the computer won’t be completely clear because neither eye is corrected for that distance.

Some doctors are also experimenting with mixing IOL types to achieve a “modified monovision”.  They may correct one eye for distance and use a multifocal IOL in the other eye to achieve better intermediate and near vision.

“Piggyback” IOLs

Sometimes the outcome of cataract surgery is less than optimal.  One option for correcting vision is to add another lens inside the eye to “piggyback” on the first IOL that was placed.

This procedure isn’t performed very often and is sometimes considered a better solution than trying to remove the first IOL and placing another one inside the capsular bag.

Blue Light Filtering IOLs

The natural crystalline lens filters blue light.  In the case of a nuclear cataract, which turns a brownish yellow haze as it matures it absorbs more and more blue light.  Many patients say that after cataract surgery things not only seem brighter but that there is much more blue light.

A blue light filtering IOL acts like the eyes natural lens in its clear state, to absorb the short wavelength, blue light.  Shorter wavelengths of light have been implicated in damage to the eye and a factor in Age Related Macular Degeneration (AMD).

The one potential drawback to a blue filtering IOL is that is may affect contrast sensitivity (CS) slightly, especially in dimmer light conditions.

IOL Cost

It used to be that Medicare would only cover the cost of a standard IOL and if you opted for a “premium” IOL you had to pay the entire out of pocket cost, not just the difference in cost.  Thankfully in 2005 they changed the rule which made it much more economically feasible for more patients to afford an upgrade to their IOL by paying the difference in cost.

Premium IOLs can typically run $2000-3000 or more per eye over the cost of a standard IOL.