Everything you ever wanted to know about cataracts

Everything you ever wanted to know about cataracts

What is a cataract?

A cataract is a change in colour of the normally clear lens of the eye

The lens, where cataracts form, is positioned behind the coloured part of your eye (iris). The lens focuses light that passes into your eye, producing clear, sharp images on the retina. This is the light-sensitive membrane in the eye that functions like the film in a camera. As you age, the lenses in your eyes become less flexible, less transparent and thicker. Age-related and other medical conditions cause tissues within the lens to break down and clump together, clouding small areas within the lens. As the cataract continues to develop, the clouding becomes denser and involves a bigger part of the lens. A cataract scatters and blocks the light as it passes through the lens, preventing a sharply defined image from reaching your retina. As a result, your vision becomes blurred. Cataracts generally develop in both eyes, but not evenly. The cataract in one eye may be more advanced than the other, causing a difference in vision between eyes.

Patients with cataracts can experience the following symptoms:

  • Frequent changes in the prescription for your spectacles or contact lenses
  • Clouded, blurred or dim vision
  • Glare or sensitivity to light
  • Yellowing or fading of colours
  • Seeing “halos” around lights
  • Problems with night vision
  • Need for extra light for reading and other activities
  • Double vision in one eye

Cataract symptoms - infographic

What causes cataracts?

Aging is the most common cause. Other risk factors include the following:

  • Ultraviolet radiation
  • Diabetes
  • Hypertension
  • Obesity
  • Smoking
  • Prolonged use of corticosteroid medications
  • Statin medicines used to reduce cholesterol
  • Previous eye injury or inflammation
  • Previous eye surgery
  • Hormone replacement therapy
  • Significant alcohol consumption
  • High myopia
  • Family history


How do you treat cataracts?

Cataract surgery undertaken by an ophthalmologistIf you have a cataract, you’ll see an ophthalmologist. This doctor specialises in eye problems. He or she will probably tell you it’s best to wait to remove the cataract until it starts to affect your daily life. The surgery can be done at a hospital or an outpatient clinic.

The surgery usually takes well under an hour. Your surgeon will make a tiny cut in the front of your eye, sometimes with the help of a laser. Through this, she’ll put in a small tool to break up the cataract and gently suction it out.

Next, she’ll put in the new lens, which is made of plastic, silicone, or acrylic, and close the cut. You won’t need to stay overnight at the hospital, but you’ll need someone to drive you home. If you have cataracts in both eyes, you’ll probably get two separate surgeries, typically a few weeks apart. This gives the first eye a chance to heal.

Types of lens implants

  • Monofocal IOL: This is the most common. Unlike your natural lens, which can stretch or bend to help your eye focus, this implant stays focused at one fixed distance. If yours focuses at a distance, you might be able to see things far away but need glasses to read or see close up.
  • Multifocal implant: Like glasses with bifocal or progressive lenses, this lens has areas that help you see things at different distances. It could take several months for your brain to adapt so your vision seems natural.
  • Accommodating IOL: This flexible option acts more like your natural lens and focuses at more than one distance. It makes you less likely to need reading glasses.
  • Toric IOL: You’ll get this is if you have astigmatism, or a cornea that’s more football-shaped than round. This can make vision blurry all over, not just close up or far away. This lens lessens astigmatism, so you won’t need glasses to correct it after your surgery.

Sleeping cat - how someone with normal vision and someone with cataracts sees itWhat are the side effects of cataract surgery?

Side effects are rare from cataract surgery and most patients are completely comfortable a day or so after surgery, but some things that could happen are:

  • Eye infection or swelling
  • Bleeding
  • Retinal detachment — the breaking away of a layer of tissue at the back of your eye that senses light
  • Drooping eyelid
  • Temporary rise in eye pressure 12-24 hours after surgery

Germs that get in your eye during surgery can lead to an infection. You might feel sensitive to light or have pain, redness, and vision problems. If this happens to you, call your doctor right away.

Infections after cataract surgery are rare, but if you have one, you’ll get a shot of antibiotics into your eye. In some cases, your doctor also removes the vitreous, the clear gel in the centre of the eye, to stop the infection from spreading.


A little swelling and redness after surgery is normal. If you have more than usual, you’ll get eye drops or other medicine to take care of it.

Retinal detachment

The retina sits way back in your eye, sensing light and sending messages to the brain. After surgery, you have a slightly higher chance that it pulls away from the back of the eye — a problem called retinal detachment.

Lens fragments

When your doctor removes your cloudy lens during cataract surgery, some pieces may fall into your eye and get left behind. Small ones aren’t a problem, but bigger ones can be. You may need surgery to remove the vitreous and prevent swelling.

Fluid build-up in the retina

Occasionally, blood vessels in the retina will leak after surgery. As fluid collects in your eye, it blurs your vision. Your doctor will treat it with eye drops, and it could take weeks or months to heal. It usually gets completely better. In more serious cases, you may need a steroid shot behind the eye or surgery.

Dislocated Intraocular Lens (IOL)

The IOL is the artificial lens your doctor puts in your eye during surgery. It can slip out of place, causing blurred or double vision.  It can also lead to more serious issues like bleeding and swelling. You may need surgery to get it back in position or to put in a new one.

Secondary cataract

The lens capsule surrounds the eye’s lens. Cataract surgery removes the front part of the lens but leaves the back in place. That’s where you may get a secondary cataract, also called posterior capsule opacification (PCO). When that happens, your vision may get cloudy again. It usually happens eventually after cataract surgery. To fix it, you need a procedure called YAG laser capsulotomy. Your doctor uses a laser to create a hole in the back of the lens capsule, which lets light pass through so that you can see normally. It’s painless and takes about 5 minutes.

Swelling in the cornea

The cornea is the clear, front part of the eye. It may get swollen and hazy after surgery, making it harder to see. This problem is almost always temporary and gets better in days or weeks. Your doctor may treat it with eye drops.


It’s rare but, during surgery, blood vessels that supply the retina may start bleeding for no reason. A little bit of blood isn’t a problem, but larger amounts could lead to loss of vision. After surgery, blood may collect between the cornea and iris — the coloured part of your eye — and block your vision. Eye drops may help, and you’ll need to rest in bed with your head up. If the blood doesn’t drain or causes too much pressure in your eye, you may need surgery.

Floaters and flashes of light

Surgery can cause posterior vitreous detachment, where the vitreous separates from the retina. It makes you see moving spider webs and clouds in your vision, along with flashes of light. Usually, it gets better on its own within a few months. Because the symptoms are similar to retinal detachment, call your doctor right away to get checked out.

High eye pressure

For some people, surgery raises pressure in the eye. It’s called ocular hypertension and can damage your vision. Your doctor may suggest you treat it with eye drops, shots, or pills. Swelling, bleeding, or leftover lens fragments can cause greater pressure in your eye, which can lead to glaucoma. How it’s treated depends on the specific reason it’s happening. If your optic nerve gets damaged, you might also need glaucoma surgery.

Light sensitivity

This can be normal, but if it lasts more than a couple of days, talk to your doctor. Sometimes, you just need to wear sunglasses for a few months until it goes away. But it could also be a sign of another issue, like too much inflammation in your eye, and you may need eye drops.

Droopy eyelid

Also called ptosis, this is a common condition after eye surgery. Doctors don’t know what causes it, but it typically goes away on its own. If it lasts more than 6 months, you may need surgery.


This causes you to see visual effects, and there are two types:

  • Negative, which gives you a curved shadow at the edge of your vision
  • Positive, which you see as halos, starbursts, flashes, or streaks of light

Doctors don’t know why it happens, and it often goes away on its own. It’s more likely to last when it’s the negative kind. Typically, you wait and see if it gets better. You might try eye drops or even glasses with thick rims, so you don’t notice the shadow as much.

If it goes on for months, your doctor may suggest surgery. You might get a new lens or try a second lens on top of the first.

Alternative treatments

Currently surgery is the only option for treatment of cataracts.


The surgery is usually covered by the hospital plan of your medical aid. A monofocal lens is covered by the medical aid. If another intraocular lens is chosen, there is usually a co-payment that needs to be made.

If you’re suffering from cataracts or suspect you might be, then get in touch with Dr Taryn Fletcher and make an appointment to see her.