Cataracts
The lens inside the eye is much like a camera lens, focusing light onto the “film,” or retina. A cataract is a clouding of the eye's natural lens, which is behind the iris and pupil. The lens is mostly made of water and protein. As we age, the protein may clump together and start to cloud the lens. This is a cataract, and over time, it will progress and cloud more of the lens, causing blurry vision.
Cataracts are the leading cause of vision loss in the United States, and are the principal cause of blindness in the world.
Half of all Americans over the age of 75 have cataracts. Approximately 4 million cataract surgeries are performed annually in the United States (2023), and that number is estimated to double within 15-20 years.
Types of cataracts include:
- A posterior subcapsular cataract occurs at the back of the lens. People with diabetes, history of an eye injury, or those taking high doses of steroid medications have a greater risk of developing a posterior subcapsular cataract.
- A nuclear cataract forms deep in the central part, or nucleus, of the lens. Nuclear, or senile cataracts are usually associated with age.
- A cortical cataract is characterized by white, wedge-like opacities that start in the periphery of the lens and work their way to the center in a spoke-like fashion. This type of cataract occurs in the cortex, which surrounds the central nucleus.
- A combined cataract is a mixture of some or all of the above mentioned types of cataract. It is very common for your physician to describe your cataract as "combined".
- A mature cataract has usually been developing for decades and has turned white. Patients with mature cataracts are often blind. This type of cataract requires more phacoemulsification energy during surgery, and also increases the risks associated with the surgery. This procedure may be labeled as "complex" cataract surgery.
Cataract Signs and Symptoms
A cataract begins as a change in the color of the eye’s natural lens, or a slight cloudiness of vision. As a cataract develops, a change in glasses prescription will often take care of the blurred vision.
Cataracts usually cause streaking around lights or halos. Driving at night may become bothersome with glare from oncoming headlights. Colors may not appear as bright as they once did, or distinguishing between colors like navy blue and black may become difficult.
The different types of cataracts mentioned above may cause different symptoms. A posterior subcapsular cataract might cause debilitating glare at night but still allow for 20/20 vision during the day. One patient with a nuclear cataract might have trouble watching the Thunder play on television, where another has trouble reading the fine print on their medicine bottles. Sometimes as a cataract develops, it shifts the prescription so the patient actually sees better without glasses. This is fortunate but won’t last forever, as the cataract will eventually progress to a point where the patient cannot see clearly with or without glasses.
What Causes Cataracts?
As Dr. Hummel always says, “If you live long enough, you will develop a cataract.” Cataracts are a normal sign of aging, but can also progress quickly, and at a younger age, for other reasons:
- Ultraviolet light from the sun
- Diabetes or high blood pressure
- Obesity
- Smoking or significant alcohol consumption
- Prolonged use of corticosteroid medications
- Certain cholesterol or hormone replacement medications
- Previous eye surgery, injury, or inflammation
- Family history
Cataract Treatment
When symptoms begin to appear, new glasses, stronger magnification, or brighter lighting may clear up any blurred vision. When these options no longer improve the vision and the patient has difficulty with everyday tasks such as reading a book, watching television, seeing street signs while driving, fine handwork, sports, etc., then it might be time to consider cataract surgery. Many people consider poor vision an inevitable fact of aging, but cataract surgery is a simple, relatively painless way to regain vision. Cataract surgery is the most frequently performed surgery in the United States, with more than 3 million Americans undergoing cataract surgery each year. During cataract surgery, Dr. Hummel gently removes the cloudy lens and replaces it with a crystal-clear intraocular lens implant. Advanced specialty lens implants are now available to reduce dependence on glasses or contact lenses after cataract surgery.