Cataract Surgery

What a cataract is, and why surgery is the treatment

The natural lens sits just behind the pupil and focuses incoming light onto the retina. A cataract is clouding of that lens. Light scatters as if it were passing through frosted glass, and everything looks hazy.

Most cataracts develop with age. Diabetes, eye injuries, long-term steroid (cortisone) use, heavy sun exposure and smoking can all contribute. The clouding progresses slowly and often starts in one eye before affecting the other.

No drop, tablet or pair of glasses can make a cloudy lens clear again. A new prescription may help for a while, but the haze stays. The only effective treatment is to remove the cloudy lens and put an artificial one in its place.

Signs that point to a cataract

• Blurred or misty vision
• Sensitivity to light, and glare from oncoming headlights
• Difficulty seeing at night
• Colours looking faded or yellowish
• Double vision when looking with one eye
• Struggling with everyday tasks such as reading or driving

Other eye conditions can cause the same complaints. A dilated eye examination shows how much of the vision loss comes from the cataract.

Do you have to wait for a cataract to ripen?

No. What decides the timing is how much your eyesight is limiting daily life. If reading has become hard work, headlights bother you when driving at night, or your glasses prescription keeps changing, it is reasonable to discuss surgery. A very hard, advanced cataract makes the operation longer and technically more demanding, so waiting for years after it starts to affect you is not recommended.

Measurements before surgery

• Biometry: Measures the length of the eye and the curvature of the cornea. These figures are used to calculate the power of the new lens.
• Corneal topography: Maps the corneal surface and shows astigmatism. It shapes the choice if a toric (astigmatism-correcting) or multifocal lens is being considered.
• Endothelial cell count: The cells lining the inner surface of the cornea keep it clear. If there are few of them, the operation is planned accordingly.
• Eye pressure and retinal examination: Glaucoma or macular disease affects how much vision can be expected after surgery.

An unstable tear film can distort the corneal readings. In that case dry eye may be treated first and the measurements repeated.

How the operation is done

The standard technique is phacoemulsification, usually shortened to phaco. It works in four steps:

1. Tiny incisions, a few millimetres long, are made at the edge of the cornea.
2. A round opening is made in the front of the thin capsule that holds the lens.
3. A fine probe vibrating at ultrasonic frequency breaks the cloudy lens into small fragments and suctions them out.
4. A folded artificial lens is passed through the same incision and unfolds inside the empty capsule.

The incisions usually seal without stitches.

Choosing the lens

The artificial lens stays in the eye for life. A monofocal lens gives sharp focus at one distance, usually far, so you will still need reading glasses for close work. In an eye with astigmatism, a toric lens can correct that as well. Multifocal, trifocal and EDOF lenses aim to reduce dependence on glasses at distance, intermediate and near, but they do not suit every eye.

Assoc. Prof. Dr. Elif Ceren Yeşilkaya goes through the options with you at the examination, based on your measurements and how you use your eyes day to day. The differences between these lenses are covered on the multifocal, trifocal and EDOF lenses page.

Why the two eyes are operated on separate days

Cataracts usually affect both eyes, yet the two are not treated on the same day. The first eye is operated on and checked, and the second is scheduled once healing is on track. That way a rare problem such as infection cannot affect both eyes at once, and the outcome in the first eye helps fine-tune the lens plan for the second.

Between the two operations, the eyes may focus quite differently. People with high short-sightedness often find their old glasses no longer suit the operated eye. How to manage this gap, for example by changing one lens of the glasses or wearing a contact lens in the other eye, is discussed at the examination.

Looking after your eye after surgery

• The eye is covered with a protective shield and you are given a schedule for your drops.
• Mild grittiness, watering and light sensitivity are normal in the early days.
• Use your drops on time. Do not rub the eye, keep water and soap out of it, and stay out of swimming pools and the sea for as long as your doctor advises. You may be asked to wear a shield at night.
• Your doctor sets the dates of your check-ups. If you need glasses, they are prescribed once healing is complete.

When you can drive or return to work is decided at a check-up, once your vision has been measured.

Risks, and haze that can appear later

Cataract surgery is a common operation, but like any surgery it carries risks:

• Infection inside the eye (endophthalmitis): Rare but sight-threatening, and it needs urgent treatment.
• Inflammation and a temporary rise in eye pressure
• Corneal swelling (oedema): Usually temporary, but can last longer if endothelial cells are low.
• Swelling at the centre of the retina (macular oedema): Can blur vision again after an initial improvement and is treated with drops.
• Retinal detachment: Rare, and more likely in highly short-sighted eyes.
• Displacement of the artificial lens

Posterior capsule opacification and YAG laser

The artificial lens sits inside the thin capsule left behind from the natural lens. Months or years later, the back of this capsule can turn cloudy, a change called posterior capsule opacification. Vision becomes misty again and many people assume the cataract has come back. It cannot, because the natural lens has gone; the haze is only in the capsule.

YAG laser treatment clears it. The pupil is dilated with drops and the laser makes a small opening in the centre of the capsule, letting light reach the retina again. There is no incision, and your eye pressure is checked afterwards.

When to seek help straight away

After surgery, do not wait for your next appointment if your vision drops suddenly, pain keeps increasing, or redness or discharge gets worse. Flashes of light, a sudden shower of floaters or a curtain moving across your vision also need to be seen without delay.

Operations are carried out at Medicana Zincirlikuyu (Şişli, Istanbul). The first step is an examination to grade the cataract and take the lens measurements. Your pupils will be dilated, which blurs vision for a few hours, so it is easier not to drive yourself to the appointment.