A cataract is a clouding of the normally clear lens of the eye. It can be compared to a clear window, which has become dirty, frosted, or fogged. Normal aging is the main factor in the formation of cataracts, much like gray hair, skin changes, and the like. The process is usually gradual, occurring over many years, but may progress more quickly. It is not possible to predict exactly how quickly a cataract will progress.
The typical symptoms caused by cataracts are blurred vision, glare, loss of color and contrast, loss of depth perception, or frequent changes in glasses. This will often affect our abilities for driving, reading, work and hobbies requiring precise vision.
In the early stages, there are usually no symptoms when a cataract is detected during an eye examination. As the cataract progresses, the symptoms are mild and often intermittent with occasional blurring of vision and glare. These symptoms gradually increase in severity and become more constant and noticeable during our routine activities as the cataract continues to develop.
Aging is felt to be the primary factor in cataract formation. But, smoking, poorly controlled diabetes, and excessive bright sun exposure over a lifetime all probably contribute to this process. Although there is no scientifically proven measures to prevent or retard cataract formation, normal doses of vitamin C and vitamin E maybe beneficial. Ultraviolet absorbing sunglasses may also be of benefit during periods of prolonged bright sun exposure.
Surgery is the only way to eliminate the diseased lens. Cataract surgery is elective and performed when the lens changes become advanced enough to significantly interfere with your visual needs. When activities such as safe driving, reading, watching TV, work activities, shopping, gardening, golfing, etc. become tedious, and slow as a result of poor vision, then surgery for the cataract is appropriate. A cataract does not need to become ripe in order to remove it.
The decision to proceed with cataract surgery is often a mutual decision between the doctor and patient. Except in unusual circumstances, a cataract will not cause any permanent injury to the eye. On the other hand poor vision can be a safety issue when driving, or traveling up and down stairs, when a cataract becomes advanced.
When surgery is appropriate, it is generally performed in an outpatient setting, without need for hospitalization. The surgery is generally performed with local anesthesia and sedation and is usually not a difficult or painful process. The natural lens removed during the surgery is typically replaced with a medical grade acrylic lens, "the lens implant". Cataract surgery is highly successful, with vision improvement in over 90% of cases. As with any surgical procedure, there are no guarantees, and there is the potential for complications, some severe enough to significantly limit visual function. This is one reason why cataracts in the early stages with little or no symptoms are observed.
In summary, cataracts are a common cause of poor vision, particularly in the elderly population. Periodic evaluation is important to monitor acuity and appearance of the cataract. When appropriate, you can expect cataract surgery to improve your vision and continue to enjoy the benefits associated with it.
At the time of cataract surgery, a lens implant is used to replace the natural lens of the eye. Options include the standard monofocal implant, the toric intraocular lens to correct astigmatism, and the multi-focal intraocular lens implant to improve unaided reading vision.
The monofocal intraocular lens typically affords good vision at distance without glasses, and prescription reading glasses or over-the-counter magnifiers are necessary for smaller print and detail. Glare and halos are generally not an issue, and the costs are covered as part of the cataract surgery fees.
Toric intraocular lens: Astigmatism is an optical condition that contributes to blurred vision. It occurs as the result of the ocular surface not being symmetrical, with light focusing at different locations in front of or behind the retina. The shape of the eye is more like a football than a basketball. Glasses and contact lenses are typically used to correct astigmatism.
The standard lens implant does not correct astigmatism. The toric intraocular lens implant, now available to correct up to 5 diopters of astigmatism, compensates for some or all the astigmatism present. When the astigmatism is corrected with a toric implant, the vision without glasses is better than if a monofocal implant is used. Reading glasses are typically still be needed, and glasses for distance may also be necessary to achieve the clearest vision.
The anticipated goal is reduction of astigmatism and better uncorrected vision (the vision without glasses) in the operated eye.
The multifocal implant is designed to focus objects at distance and close-up such as reading and computer use. This generally allows good vision for many tasks without the need for glasses. By the nature of the lens design, glare and halos with the multi-focal intraocular lens are more prominent . These symptoms typically improve over weeks to months. In rare instances, they may need to be removed if these symptoms do not resolve.
All of the implants work well. The premium lens implants, which do require additional fees, have the added benefit of reducing the need for glasses, improving unaided or uncorrected vision, allowing for a spectacle free experience. Explain to the doctor and staff what your visual needs and expectations are, so you can choose the implant that works best for you.