Cataracts are an extremely common eye condition and are often misunderstood. Frequently called a “cadillac” (as shown on our home page–a Cadillac V-63 Tourer Cabrio), many people believe that a cataract is a growth over the surface of the eye. Rather, it is a clouding of the natural crystalline lens inside the eye over time.
When the natural lens inside the eye becomes unclear, the condition is called a cataract. It prevents the formation of clear images on the retina, the nervous tissue lining the back of the eye, and therefore, the retina must send signals of a cloudy image to the brain. The end result is that the patient does not see well. Cataracts are the leading cause of poor vision in adults, and they worsen with age. Cataract formation can be accelerated in patients with illnesses (such as diabetes), the use of certain medications (such as corticosteroids), or in the event of ocular trauma. Each year, it is estimated that 20 million cataract surgeries are performed across the world, attesting to the safety, efficiency and need of this procedure.
How Can Someone Know Whether They Have a Cataract?
Visual problems are often the first symptom of cataract, although early cataracts are often free of symptoms. Patients with cataract will often complain of hazy, blurred or dim vision. They may feel that colors appear weak or washed out. They may notice that reading or watching television is difficult because the image is not clear. They may find that driving at night becomes difficult because of glare and that bright sun seems extraordinarily annoying. These patients often see a local eyecare provider such as an optometrist who discovers that the patient’s vision cannot be improved with spectacles and will usually diagnose the cataract.
When Should Cataracts Be Removed?
A complete eye examination with pupil dilation is necessary to determine if the visual complaints are due to cataract and whether cataract is the only problem causing the patient’s symptoms. Notably, cataracts are more common in the elderly, and this population more often suffers other vision threatening diseases such as glaucoma and macular degeneration. If a cataract interferes with the patient’s ability to enjoy daily activities, cataract removal is often recommended. An ophthalmologist should reassure the patient that it is rare for a cataract to cause permanent damage in the eye, therefore the cataract can often be left alone for years if the patient so chooses. In addition, the ophthalmologist should advise patients that cataract extraction is one of the safest operations performed today.
Cataract Surgery with intraocular implants
The surgical procedure for cataract removal has evolved rapidly over the last twenty years. Our doctors offer the latest micro-incision phacoemulsification procedure to all patients. During the procedure, the surgeon breaks up the cloudy cataract into small pieces and removes them using a very sophisticated ultrasonic vacuum called a phacoemulsification system. A thin, foldable artificial lens called an intraocular lens (IOL) is then inserted into the eye, and implanted where the cataract was removed. Patients experience less post-operative irritation, almost no physical limitations, and rapid visual recovery after surgery.
Astigmatism is a common eye condition due to an irregularly shaped cornea. The cornea should be a spherical shape, but with astigmatism, it is shaped like a football resulting in blurred vision or double images at all distances (near and far). Most people have at least a small amount of astigmatism, but almost 1/3 of all people have enough astigmatism to cause blurry vision warranting treatment. Astigmatism can be treated with glasses, contact lenses, or surgery. Standard cataract surgery does NOT correct astigmatism, so employing one of the options below can be very helpful for patients with significant astigmatism.
Treating Astigmatism During Cataract Surgery
There are two treatment options at the time of cataract surgery to reduce astigmatism. Both treatments are meant to reduce the need for glasses or contact lenses for good far vision after surgery. These treatment options include laser-assisted cataract surgery and implantation of a Toric Intraocular Lens (IOL). It’s important to note that patients who select these options will very likely still need reading glasses for activities within arm’s length—see “presbyopia” below for more information.
Laser-Assisted Cataract Surgery (LenSx®)
The LenSx® laser is designed to provide patients with an optimized refractive cataract surgery experience. Traditionally, cataract surgeries have been performed manually where the surgeon uses a blade to create all of the incisions during the procedure. With the introduction of the FDA-approved LenSx® femtosecond cataract laser, our surgeons now have the ability to create incisions and reduce astigmatism with a laser. Each incision, called an arcuate keratotomy, is more accurate and precise, thereby enhancing the predictability of refractive outcomes. This technology can frequently be combined with the use of a Toric IOL to maximize astigmatism treatment.
Another option that is very helpful for patients with moderate to high astigmatism at the time of cataract surgery is the implantation of a Toric Intraocular Lens. This IOL, similar to prescription spectacles, has astigmatism correction, called cylinder, built into the lens. The amount of cylinder is chosen by the surgeon based on very precise measurements taken of a patient’s eye prior to surgery. This IOL can be implanted at the time of surgery and accurately aligned by the surgeon to help neutralize astigmatism and reduce a patient’s need for glasses post-operatively. The Toric IOL is frequently used in combination with laser-assisted cataract surgery to maximize refractive precision.
Almost all patients over the age of 40 encounter an aging phenomenon in their eyes called presbyopia. Presbyopia is a loss of accommodation, the process through which the eyes can change focus from far to near. Patients in this scenario find themselves requiring glasses to see clearly up close, and this same phenomenon is encountered after standard cataract surgery.
Treating Presbyopia During Cataract Surgery
There are two main treatment options that our doctors offer at the time of cataract surgery to reduce a patient’s dependence on reading glasses for activities within arm’s length (reading, computer use): monovision and multifocal IOL’s.
One option to treat presbyopia is called monovision. Monovision is a strategy that offsets the refractive target in each eye so that the eyes complement each other. One eye is set to see well far away (television, driving), and the other is set for near (reading a book or computer screen). This approach is very effective for patients who had success in the past with monovision using contact lenses. For those who have never worn contacts but are still interested in this treatment option, a contact lens trial can be conducted by an optometrist to simulate postoperative vision in each eye to ensure the patient’s comfort prior to making permanent changes through surgery.
The second option to treat presbyopia during cataract surgery is to implant multifocal intraocular lenses (IOL’s). These lenses use advanced technology (diffractive optics) to provide both near and far vision to each eye. They significantly reduce the need for glasses at all distances, and are a great advance in the field of refractive cataract surgery. Just like joint replacements, these IOL’s can enhance the lifestyle of patients but still have limitations when compared with the natural crystalline lenses that God gave each of us. In clinical trials, multifocal IOL’s have been associated with significant glare and halos in up to 5% of patients who have them implanted. For these reasons these IOL’s are not recommended for pilots or those that spend a significant amount of time driving, especially at night. Frequently, the use of multifocal IOL’s is combined with laser-assisted cataract surgery to optimize surgical precision, treat any amount of astigmatism present, and maximize the chances of excellent vision after surgery.