A Primer on Modern Cataract Surgery
by Tyrone McCall, M.D.
Cataract surgery is the most commonly performed outpatient surgery in the US. Major advancements in technology and technique have allowed millions of people to have vastly improved eyesight and, for some, the chance to be independent from glasses for the first time in their life. As the Baby Boomer generation expands the cataract patient population, demand will continue to facilitate advancements in this rewarding surgery.
The natural lens focuses light to the retina, creating an electrical signal that is then sent to the visual portion of the brain for processing. A cataract is merely a clouding of the natural lens, which sits behind the iris (the colored part of the eye). As a cataract progresses, typical visual symptoms include blurred vision, reduced night vision, difficulty in low lighting or low contrast situations, poor color discrimination and glare/halo from lights.
Everyone gets a cataract if they live long enough, with the average age of a cataract patient in the mid to late 60’s. The most common type of cataract (nuclear sclerosis) is associated with the normal aging process; other factors associated with cataract development include genetics, diet, systemic medicines, general health issues, and trauma. Although the development of a cataract over time is inevitable, cataract surgery is only rarely emergently needed. The typical scenario that compels us to recommend cataract surgery is when the patient notices that their blurred vision is affecting their daily life and activities. Once quality of life is affected by vision, cataract surgery becomes an excellent option to improve vision.
Cataract surgery is done on an outpatient basis, with either topical or local anesthesia. The surgery involves making a small incision in the cornea, allowing access to the interior of the eye. An opening is then made in the capsule that holds the natural lens in place. The lens is broken into small pieces by an instrument that then aspirates it from the eye. A clear lens implant is then inserted into the same capsule that held the natural lens. The eye can either be patched or left uncovered depending on the type of anesthesia used.
There are 3 styles of lens implant: standard, astigmatism (also called toric), and multifocal. A standard lens implant is like a fixed focus camera. It can give excellent distance, intermediate, or near vision, but only one of these. For example, if a patient chose distance vision, they would be able to drive a car or watch TV without glasses, but would need reading glasses for near vision. An astigmatism implant is a specialized version of a standard implant. Astigmatism is an asymmetric curvature of the cornea and, if not corrected, leaves vision blurred at all distances. A multifocal implant is the most flexible option, allowing for distance, intermediate, and near vision. Until recently, patients with astigmatism were not good candidates for this implant. New lens implants are now available that correct astigmatism and give the flexibility of a multifocal implant lens. Although there is no perfect lens implant, this lens allows the greatest independence from glasses. Each lens serves a different function and can be tailored to each patient’s visual needs. You should discuss your specific visual needs with your surgeon so an implant can be chosen to best suit those needs.
As with any surgery, there are some risks associated with this procedure including bleeding, infection, damage to other parts of the eye, and the need for more surgery. These complications are extremely rare and advancements in surgical equipment, surgical techniques, and medicines make cataract surgery an extremely safe and effective procedure.
Patients frequently ask if a laser is used to remove the cataract. Femtosecond laser technology, which has been used in LASIK refractive surgery for over a decade, is becoming a welcome technologic advancement in modern cataract surgery. This laser can assist in the creation of the corneal incision, opening of the anterior capsule, and lens fragmentation. Even though the laser can replace some of the surgical instruments used in cataract surgery, there is no truly automated surgery.
Your surgeon can best address any question or concerns regarding your cataracts or cataract surgery, which is another reason it is so important to follow up regularly with your eye care professional.