Cataract Surgery & IOL Options
In its infancy, the principal goal in cataract removal was simply to clear the visual axis. Though the objective has not changed, with the advent of phacoemulsification, foldable intraocular lenses, ophthalmic viscoelastic devices and smaller incision sizes, cataract removal today has progressed into an intraocular refractive procedure. As refractive cataract surgery has improved so have patient expectations. Many cataract surgery patients today expect to be spectacle free at least when it concerns their distance vision. Thankfully there are many options our practice offers to give our patients the greatest possible visual outcome.
Foldable posterior chamber intraocular lenses were first FDA approved in the 1990s. These monofocal IOLs are composed of silicone and hydrophobic acrylic materials. The first silicone IOL was introduced by Allergan while the first hydrophobic acrylic IOL was introduced by Alcon. The aforementioned IOL materials comprise the two most commonly used IOL materials in the United States. The newest class of foldable IOL materials to become FDA approved is the hydrophilic acrylic, or hydrogel class. Their market share is much smaller than that of the silicone and hydrophobic acrylic materials. All of these foldable IOLs are safe, of excellent optical quality, FDA approved, and produce outstanding visual outcomes. While every cataract surgeon may have his or her favored IOL preference, no clear superiority of one material over another has ever been demonstrated. Our practice utilizes a foldable silicone IOL for patients who choose a monofocal IOL option.
For patients who desire greater spectacle independence than what a monofocal IOL can provide, our practice offers both toric and multifocal IOLs as premium options. Toric IOLs have been available since 1998 and are used for the correction of astigmatism. Our practice offers both the Tecnis Toric IOL from Abbot Laboratories and the AcrySof IQ Toric IOL from Alcon. We recommend these lenses to patients who are interested in decreased spectacle dependence at distance with decreased residual astigmatism after cataract extraction. Toric IOLs can correct preexisting corneal astigmatism in the 0.75 D to 4.75 D cylinder range. It is important to educate these patients to the likelihood that they will still need spectacles for near vision but had they not chosen a toric IOL they would have needed spectacles for BOTH distance and near visual activities.
Multifocal IOLs have come a long way since their introduction in 1998. The earlier versions of these lenses did offer better spectacle independence than the standard monofocal IOL but patients still found the need to use spectacles for either intermediate or near visual activities. As you can imagine this could be highly frustrating for the patient (and the physician for the matter) if the multifocal IOL did not match their lifestyle. For the patient who is an artist or avid outdoorsman, for example, rich intermediate vision is critical for the patient to happily continue their way of life. For the patient who values closer activities such as reading fine print on a computer tablet or magazine then vibrant near vision is at a premium. Our office is absolutely able to evaluate and meet the unique needs of all of our patients who are choosing a multifocal IOL. We have had great success with the use of the Tecnis Multifocal IOL. This lens is offered in three different near add powers tailored to the patient’s desired lifestyle. The +2.75 add IOL is tailored to patients who value intermediate vision, the +3.25 add is offered for those who value longer reading distances, while the +4.0 add is presented to those who prefer near vision requiring fine detail.
Not every patient is a candidate for a multifocal IOL. Patients with more than 0.75 D of corneal astigmatism are not good candidates for this lens because the lens does not correct for astigmatism at this time. We are expecting that the next generation of multifocal IOLs will also contain astigmatic correction. Some surgeons use limbal relaxing incisions to compensate for residual astigmatism but the refractive outcome of these incisions can be difficult to predict. The best candidates are patients with a spherical cornea. Complications from implantation of this lens do not differ from complications of a routine cataract surgery.
Since its inception, cataract surgery has developed into a procedure that has brought great satisfaction to both the patient and the physician. Cataract surgery today is truly another available option among other refractive procedures. Patient expectations have greatly increased but we are absolutely able and ready to meet this challenge. Today with the careful evaluation of visual habits, occupational needs, leisure activities, multimedia needs, and personality of our patients, our office is able to deliver the best outcomes regardless of which IOL a patient chooses.