When to Have Cataract Surgery: How a Surgeon Actually Decides the Timing

"Dr. Kim, my optician says I have a cataract but it's 'not ready yet' — so when should I have cataract surgery?"

I hear some version of this almost every week, often from patients who have been told to simply wait. It's one of the most misunderstood questions in eye care, so let me answer it the way I would across the desk — plainly, and without rushing you toward an operating room you may not need yet.

The "wait until it's ripe" myth

For decades, surgeons did delay cataract surgery until the lens turned hard and milky — because the older techniques genuinely needed that. Those days are gone. With modern phacoemulsification we remove a soft, early cataract more gently than a dense, mature one. So the idea that you must let it "ripen" is not only outdated, it can work against you: a rock-hard lens takes more ultrasound energy to break up and stresses the delicate tissues inside the eye.

So I almost never tell a patient to wait simply because the cataract is small. I tell them to watch how it makes them feel.

The real question: what is it costing your daily life?

Here is the test I actually use. Forget the size of the cataract for a moment and ask yourself honestly:

• Are headlights and street lamps throwing halos or starbursts that make night driving stressful?
• Has reading, sewing, or screen work become tiring even with the right glasses?
• Do colours look duller, or is there a yellow-brown wash over everything?
• Have you changed glasses twice in two years and still feel unsatisfied?
• Are you quietly giving up things — evening drives, fine print, stairs in dim light — because your sight feels unreliable?

If you're nodding at several of these, the cataract is no longer a lab finding. It's affecting your life, and that is the moment surgery starts to make sense.

What I look at during the exam

When you come in, I confirm that story with the eye itself. On the slit-lamp I grade where the cloudiness sits — a posterior subcapsular cataract, for instance, can wreck your reading and glare tolerance while still looking "mild," whereas a slow nuclear cataract may look denser but bother you less. I check your corrected vision, your glare sensitivity, and the health of the rest of the eye: the cornea, the pressure, the retina, the optic nerve.

That last part matters. Sometimes a patient's blur is partly the cataract and partly something else — early macular change, dry eye, glaucoma. I'd rather find that out before surgery than have you disappointed after, expecting the lens swap to fix a problem it was never going to fix.

When waiting is the wrong choice

Most cataracts are patient and slow, and a measured wait is perfectly reasonable. But a few situations push me to recommend not delaying:

• A lens that has become very dense or intumescent (swollen), which can crowd the eye and raise pressure.
• A cataract so cloudy I can no longer see the retina well enough to monitor another condition.
• Vision that's already below the legal threshold for driving, when driving is part of your livelihood or independence.

In those cases I'll say so directly. Otherwise, the timing is largely yours to choose.

One eye first, then the other

People often ask to have both eyes done at once to save a trip. I understand the logic, but I usually treat one eye, see you the next day, and schedule the second eye a short while afterward. It's safer, and it lets me refine the second eye's lens choice using what the first eye taught us. If you're flying in from abroad, we simply plan a slightly longer stay around that rhythm.

One honest limitation

I can't tell you your right timing from a blog post, and I won't pretend otherwise. Two people with identical-looking cataracts can need completely different advice depending on their jobs, their driving, their other eye conditions, and what they want their vision to do. Anyone who quotes you a surgery date before examining your eyes is guessing. The decision deserves an actual exam.

Talk to us before you decide

If you're weighing the timing, the simplest next step is to tell us what you're experiencing. Message us in English on our official WhatsApp or LINE — no appointment, no charge for the question. Share your age, what's bothering you, whether one eye or both feels affected, and any history of glaucoma or retinal issues. I'll give you an honest first read on whether it sounds like a "watch it" situation or a "let's plan it" one, with an English-speaking interpreter on hand throughout.

And the fee, whenever you do proceed, is the same one a Korean patient pays — no foreigner mark-up. The timing should be about your eyes, never about the bill.

— Dr. Kim Sun-young, Medical Director, Healing Eye Clinic