Understanding Cataracts: What they are, how they are treated, and what to expect

If you have recently been told you have a cataract, or you have simply noticed that your vision is not quite what it used to be, it is natural to feel uncertain. The good news is that cataracts are common, well understood, and highly treatable. This guide walks you through what a cataract actually is, why it develops, and what the journey through diagnosis, surgery and recovery really looks like, so that you can arrive at your consultation feeling informed rather than anxious.

What is a cataract?

Everyone has a lens inside the eye. It is easy to picture if you think of the lenses in a pair of glasses, the eye has its own natural lens sitting inside it. When you are young, that lens is clear, and plenty of light passes through it to the back of the eye, where vision is formed.

As we get older, the lens ages too. It gradually becomes cloudy, and that cloudiness is what we call a cataract. When less light is able to reach the back of the eye, vision begins to be affected. It is a slow, natural process for most people, which is part of why it can go unnoticed for some time.

Are there different types of cataracts?

Yes. Cataracts can take different forms depending on which part of the lens becomes cloudy, and they can behave differently as a result.

The most common is a nuclear cataract, where the central part of the lens becomes dense and vision gradually deteriorates over time. A cortical cataract affects the outer part of the lens, and patients with this type often complain of significant glare. There is also a posterior subcapsular cataract, which sits right in the centre of the lens at the part responsible for bending light onto the retina, and because of where it sits, this type can affect vision quite early.

The early signs people often miss

Cataracts tend to be easy to explain away. If you are noticing a lot of glare, it is tempting to assume it is simply a bright day and that you need sunglasses. If your vision is slowly declining, you might put it down to getting older and leave it at that.

These explanations are understandable, but they can delay a simple check that would give you clarity. Glare and a gradual blurring of vision are worth having looked at, not because they are alarming, but because knowing what is going on puts you back in control.

Who gets cataracts, and at what age?

There are several causes. By far the most common is age-related cataract, which develops naturally as the lens gets older. But cataracts are not only a condition of older age.

Some health conditions can bring them on earlier. Diabetes and other systemic diseases that affect the body's metabolism are associated with cataracts forming sooner. Some people are born with cataracts, we call these congenital cataracts. Trauma to the eye can cause one, and so can severe inflammation inside the eye. So while age is the usual reason, it is genuinely a case-by-case picture.

Lifestyle and the eye

The eye is part of the body, so the choices that affect our general health affect our eyes too. Smoking, a poor diet, and spending a lot of time in the sun without eye protection can all damage the structures inside the eye, including the lens. None of this needs to cause worry, it simply means that looking after yourself, and reaching for sunglasses outdoors, is looking after your eyes as well.

What brings patients in, and how a cataract is diagnosed

Often, the first step happens at the optometrist. A patient goes in thinking they need new glasses, and the optometrist picks up a cataract and refers them on.

Other times, people notice it themselves, for example, when they happen to cover their good eye and suddenly realise how little they can see out of the other. In most cases, it is a noticeable drop in vision that prompts the visit. This is one of the quiet reasons regular eye checks matter, even when nothing feels wrong.

Diagnosis itself is straightforward and comfortable. First we check how well you see. Then we examine the eye on a slit lamp, a machine that magnifies everything so we can have a good, detailed look at what is happening inside the eye.

When is surgery needed?

This depends entirely on your vision. If you still see well, or your vision can be corrected with glasses, you do not need cataract surgery, and the cataract can simply be monitored. But once vision is genuinely reduced by the cataract, surgery is the only way to improve it.

It is worth being clear about this: there are no drops or medications that make a cataract go away once it is causing visual problems. If a cataract is interfering with everyday life, whether reading, driving, screens, or simply looking after yourself, then surgery is the route to better vision. Most people do not wait until they can see nothing at all; the right time is usually when day-to-day tasks start to become a struggle.

What happens on the day of surgery

Cataract surgery is done in a surgical facility, such as a day hospital. It is an in-and-out procedure, which means there is no need to stay overnight.

When you arrive, the nursing team prepares you for the operation, and drops are placed in the eye to widen the pupil so that the surgeon can see the lens clearly. In theatre, you lie comfortably on your back, looking upwards. The eye is numbed, most commonly with topical anaesthesia, using drops and a small injection, although some surgeons may prefer to send the patient to sleep. The approach depends on the surgeon and on what is right for you.

How the cataract is removed

The most common technique is called phacoemulsification. Through very small incisions on the side of the eye, a phaco machine uses ultrasound energy to break the cataract into small pieces and gently suction them out. A new artificial lens is then placed into the eye to replace the old one. Because the incisions are small, there is less inflammation and healing tends to be faster, which is why this is generally the preferred approach.

Very hard cataracts are a little different. They require a great deal of ultrasound energy to break up, so it can be safer to remove them whole through a slightly larger incision on the white of the eye. An artificial lens is still placed into the eye afterwards. Throughout, the surgeon works under a microscope, because these are very tiny structures that need to be magnified to be seen properly.

Choosing a lens

Several types of artificial lens, or intraocular lens, are available, and the choice is a discussion between you and your surgeon based on your visual needs and the examination.

A monofocal lens allows you to see clearly at one specific distance and may be a good fit if the cornea does not have much astigmatism. A toric lens corrects for astigmatism, the same way toric lenses do in glasses. A multifocal lens, again like its equivalent in glasses, allows for a range of distances. Which one suits you depends on the examination and on what your surgeon feels will be both effective and safe for you.

What about laser-assisted surgery?

Laser-assisted cataract surgery is not necessarily better than traditional surgery, and the difference is often overstated. Lasers add notable cost and time to the procedure, and the cuts a laser makes can be achieved by a skilled surgeon with the same precision and the same results.

Recovery, results and risks

On the first day, it is normal for the front of the eye to be a little swollen, for there to be some inflammation, and for the pupil to still be dilated from the drops. So your vision may be blurry at first, then improve gradually. Some people are fortunate and see well from day one, but it helps to expect some inflammation, because any time an organ is operated on, it responds that way. To manage this, we always prescribe anti-inflammatory drops to use after surgery.

How common are complications?

Cataract surgery is considered one of the safest surgeries there is. As with any operation there is a risk of infection, but it is very low: an antibiotic is injected into the eye during the procedure, and the eye is thoroughly cleaned beforehand to reduce the chance of any bacteria entering.

Other complications depend partly on the surgeon's experience and skill. The lens sits within a thin capsule, which we aim to keep intact so the new lens can rest inside it. Occasionally this capsule can break during surgery, known as a posterior capsular rupture, but even then a lens can usually still be placed, simply in a slightly different position.

Caring for your eye afterwards

A shield is placed over the eye to protect it, so that if it is accidentally bumped, the shield takes the knock. For the first week or so, avoid heavy lifting and vigorous exercise, including activities like yoga or Pilates where you are upside down. And if you smoke, stopping before and after surgery is a good idea. Reassuringly, many patients are able to return to work the very next day if they wish.

Clearing up the myths

The biggest myth worth dispelling is that cataract surgery is painful. It is not.

Some people also worry about blindness, or imagine that the eye is removed during the operation. Neither reflects reality. Cataract surgery is one of the safest operations in the world, and the chance of blindness is very small. The eye is not taken out, we operate on the eye while it stays exactly where it is. And once a cataract has been removed, it does not come back.

Can anything slow a cataract down?

Following a generally healthy lifestyle reduces the risk of most eye problems. Stopping smoking is especially worthwhile, as it harms many organs in the body, the eye and its lens among them.

A final word

Cataracts are a normal part of how the eye ages, and treating them is one of the most routine and successful procedures in medicine. If you have noticed changes in your vision, the most useful step is simply to have your eyes checked. Understanding your options ahead of time means you can come to your consultation informed, ask better questions, and make the decision that is right for you, without fear of the unknown.

Dr Mpopi Lenake | Ophthalmologist & Eye Specialist | Somerset West, Western Cape

This article is for general education and does not replace a personal consultation. If you have concerns about your vision, please book an eye examination.