A cataract is a cloudiness that forms in the lens of the eye. Normally, the lens is clear to allow light to enter into the eye structures for the retina to form a visual image. When proteins in the lens clump together, they can become less clear and hence form a cloudy spot called a cataract. This spot causes some of the light entering the eye to scatter and blocks some of this light, resulting in blurry vision.
The lens of our eye is normally transparent. In people with normal vision, the pathway for the light to pass through from the pupil to the lens is clear so that the light can easily be transmitted into the retina. Much like the lens in a camera, the eye’s lens has to be clear so that light can enter the eye and allow the light sensors in the retina to form a visual picture. In people with cataract, the cloudiness of the lens prohibits light to enter the lens completely. Just like a dirty camera lens would cause a blurry picture, a cataract can cause blurriness and haziness in vision.
What is a Cataract? How Does It Form?
The lens is mostly made up of water and proteins. As we age, the lens continues to grow layers of fibers, which can cause stiffening of the lens material. This may then lead to changes in the lens proteins, causing them to change color and clump together. The clumping together of these abnormal lens proteins produces clouding of the lens called a cataract. A cataract usually starts out as very mild clouding that barely has an effect on your vision. It may seem as if looking through a frosty window or a foggy windshield. Over time, the eyesight may start getting more hazy or blurry. This happens until such time that the cataract causes major vision problems and has to be addressed.
Cataracts are very ubiquitous as we age and represent the typical aging process of the lens, though each person’s rate of clouding can be different. Moreover, there are other possible factors that may cause their occurrence. Cataracts may also be due to congenital or genetic causes, or can be caused by medications, diseases or eye injuries.
Who is at Risk for a Cataract?
Old age is the leading risk factor for cataract formation. As we age, the lens becomes less flexible and less transparent, making it easier for proteins to form clumps that result to cataract formation. Globally, cataracts account for most cases of blindness in the elderly. Aside from the inevitable aging process, these other factors may make you more at risk to contracting cataracts:
- Diseases like diabetes, obesity and high blood pressure
- Close relatives and family members developing cataracts
- Lifestyle factors like cigarette-smoking and frequent exposure to sunlight and UV rays
- Previous eye injuries or eye conditions involving swelling
- Previous eye surgery
- Use of medications such as oral and inhaled steroids or a combination of these
What are the Signs/Symptoms of a Cataract?
Patients who have cataracts may have the following signs and symptoms:
- Blurry or hazy vision
- A “halo” or glare when looking at bright lights, such as headlights from oncoming cars
- Difficulty with distinguishing colors and recognizing faces
- Double vision in one eye
- Difficulty seeing at night or in dim light
Some patients say that they experience an improvement in looking at near objects during the earlier stages of a cataract. However, this improvement goes away as the disease continues to progress.
How are Cataracts Diagnosed?
Your ophthalmologist will conduct an eye exam where he will administer eye drops to dilate your pupil for easy viewing of underlying structures. Then, he may use the following tests to establish a cataract diagnosis:
Slit-lamp Exam – This exam uses a biomicroscope to see different areas at the front portion of the eye. This allows the ophthalmologist to examine structures such as the lens, eyelids, conjunctiva and other parts to determine if any abnormalities exist.
Visual Acuity Test – This test determines how clearly you can see objects at a certain distance and helps identify any visual problems and the conditions that may cause them. A problem with looking at objects clearly may be a sign of cataract formation.
Brightness Acuity Testing – This test tries to recreate the difficulty that one experiences in more real-world conditions, such as being outside during a bright day or driving at night with opposing headlights. Often the visual acuity in the exam room can misrepresent the visual disability caused by these cataracts in a more realistic environment.
How is it Treated? What Can I Expect on Surgery Day?
Once a cataract becomes very severe and starts to affect daily activities, the only option is cataract surgery. This procedure is very common and is usually performed safely without any complications. With a high success rate of 95+ %, it has been proven to effectively improve a patient’s vision. Cataract surgery is an outpatient procedure and takes only around 30 minutes to perform, without the need for an overnight hospital stay.
During the procedure, the doctor gives you a topical anesthetic for you not to feel any pain. He then proceeds to make a small incision, remove your eye’s cloudy lens and then replaces it with an artificial intraocular lens implant (IOL). This implant remains permanently in place and becomes a part of your eye, functioning as a new, clear lens in place of the old lens. Today, there are different kinds of IOLs that are designed for various functions and made from different types of materials. Your ophthalmologist will determine which is the most suitable for your situation and lifestyle.
After the surgery, the doctor will give you an eye shield and some eye drop medications. Make sure to take the eye drops as instructed to promote faster and proper healing. Immediately after the procedure, after a period of rest, patients are typically allowed to go home on the same day. Adequate rest is highly encouraged, and strenuous activities should be avoided. After some recovery time, the vision should improve little by little and clear significantly. Several follow-up appointments will be scheduled for your doctor to check if your eye is healing properly and if the surgery was effective.
Your ophthalmologist will guide you through the process of diagnosis and treatment for you to determine if cataract surgery is for you.