How Do I Know If I Need Cataract Surgery?

You may need cataract surgery when a cataract is reducing your vision to the point where it affects your daily life, whether that is driving, reading, recognising faces, or working. A cataract is not removed based on how it looks under a slit lamp. It is removed when it is causing problems for you. Your ophthalmologist will assess your visual acuity, the density of the cataract, and how much it is limiting your function before recommending surgery.

What are the symptoms of a cataract that needs surgery?

The most common symptoms that indicate a cataract may need to be removed include blurred or hazy vision that does not improve with a new glasses prescription, increased glare or halos around lights particularly when driving at night, colours appearing washed out or yellowed, frequent changes in your glasses prescription over a short period, difficulty reading even with adequate lighting, and a feeling that your vision is foggy or like looking through frosted glass.

Not all of these need to be present. For many patients, glare on the road at night is the symptom that finally prompts them to seek assessment.

What visual acuity level typically leads to surgery?

There is no single threshold. A visual acuity of 6/12 or worse is often used as a general guide, but a patient with 6/9 vision who cannot drive safely at night may be a stronger surgical candidate than a patient with 6/18 vision who is not visually demanding. The decision is always individual.

Functional impairment matters more than the number on the chart. Your ophthalmologist will ask about your occupation, hobbies, driving status, and which eye is dominant before making a recommendation.

Can I wait, or does a cataract need to be removed urgently?

In most cases, cataracts progress slowly and waiting is a reasonable option if your vision is still adequate for your daily needs. Surgery is elective for the vast majority of patients.

There are exceptions where earlier intervention is recommended. A very dense cataract, sometimes called a mature or hypermature cataract, becomes technically more difficult to remove over time. Cataracts that cause a secondary rise in eye pressure, such as phacolytic or phacomorphic glaucoma, require urgent surgery. Your ophthalmologist will advise you if your cataract is in a category where delay carries risk.

What does the assessment for cataract surgery involve?

A full cataract assessment includes measurement of your visual acuity, a slit lamp examination to assess the type and density of the cataract, measurement of your intraocular pressure, and biometry, which involves precise measurements of your eye used to calculate the power of the lens implant. Your ophthalmologist will also assess your macula and optic nerve to ensure no other condition is limiting your vision.

This assessment also determines which type of intraocular lens is most appropriate for your eye and lifestyle. See our intraocular lens options guide for a full explanation of the choices available.

What if I have other eye conditions as well as a cataract?

Cataracts often coexist with other conditions such as macular degeneration, glaucoma, diabetic retinopathy, or corneal disease. Your ophthalmologist will assess whether the cataract is the main source of your vision loss, or whether another condition is also contributing.

In some cases, cataract surgery is combined with other procedures, for example cataract removal combined with a corneal transplant in patients with Fuchs endothelial dystrophy, or combined with glaucoma surgery. These combined procedures require a surgeon with subspecialty experience. See our overview of phacoemulsification cataract surgery for more on the surgical technique involved.

When should I see an ophthalmologist rather than waiting for my optometrist to refer me?

Your optometrist will typically refer you when they detect a cataract affecting your corrected visual acuity. However, you can also request a referral proactively if your symptoms are bothering you and your optometrist has noted a cataract on examination. You do not need to wait until your vision reaches a specific level.

If you experience a sudden change in vision, pain, or significant glare that has worsened rapidly, seek assessment promptly rather than waiting for a routine appointment. For information on what to expect in the period after surgery, see our guide on what to expect during recovery.