What is a cataract?
When asked, many people wrongly believe that a cataract is a “film” or “growth” that forms over the eye.A cataract is actually within the eye itself, and not normally visible from the outside.
Inside our eyes, just behind the pupil, is a lens. This lens, much like the lens of a camera, allows the eye to focus on objects at different distances. When young, this lens is clear. As we age, the protein within the lens degenerates, resulting in clouding of the lens. The cloudy lens is called a cataract.
Why do cataracts form?
Most cataracts are simply the product of natural aging of the lens of the eye. Therefore, everyone’s eyes will form cataract over a certain age. Cataracts are commonly seen over the age of 50 years old, and most commonly cause symptoms over the age of 60 years old.
Some conditions may cause specific types of cataract, or accelerate the formation of cataract. These include:
- Prolonged exposure to sunlight, or radiation
- Certain medications, particularly oral steroids
- Eye trauma
- Eye inflammation
- Congenital (present at birth)
- Hereditary (strong family history of cataracts)
What are the symptoms of cataract?
Cataracts are generally slow-growing in most patients, and symptoms usually come on quite gradually (over months to years). Occasionally, patients may experience quicker onset symptoms.
Patients will often experience one or more of the following symptoms with cataracts:
- Blurred or hazy vision (for near, far or both)
- Doubling or “ghosting” of the edge of objects
- Glare or sensitivity to bright lights during the day
- Reduced night vision, and haloes/starburst around headlights or streetlights
- Wearing your usual prescription glasses no longer gives clear vision
Cataracts may cause the focus of the lens to become more short-sighted (“myopic shift”). Patients may therefore find that they can suddenly read without their prescription glasses. They may also find that they have to change their prescription glasses more frequently. In the early stages of cataract, patients may feel that their glasses need to be “strengthened” to improve their vision. However, as cataract progresses, changing glasses will no longer improve the vision. This is not the fault of the glasses, but rather that the cataract now needs to be addressed.
When is the right time for cataract surgery?
There is no right or wrong time for cataract surgery. As every patient has different visual needs for their activities and lifestyles, they will differ as to the optimal time for their cataract surgery.
As the safety and outcomes from modern cataract surgery have improved to such remarkable levels, we no longer wait for cataracts to become “hard”, or for vision to deteriorate significantly, before recommending surgery. In fact, the more advanced or “mature” a cataract, the riskier the surgery. As such, we will generally recommend surgery as soon as patients experience symptoms, or if their reduced vision is beginning to limit important activities such as driving and reading.
Dr Then will help guide patients as to the safest and most appropriate time for their cataract surgery.
How is cataract treated?
There is only one treatment for cataract, and that is surgery. In cataract surgery, the cloudy lens is removed and replaced with a clear artificial lens (intraocular lens implant). This restores clear and optimal vision to the eye.
Can cataracts be treated with laser?
Cataracts are currently treated with surgery, not with laser alone.
However, a recent development is that of Femtosecond Laser-Assisted Cataract Surgery (FLACS), in which femtosecond lasers are used to assist in various steps of the traditional cataract operation, but not to do the entire operation itself.