LASIK vs Cataract Surgery: What Is the Difference?

“Is cataract surgery basically LASIK?”

Patients ask me this surprisingly often.

The answer is no.

LASIK and cataract surgery are completely different procedures. They operate on different parts of the eye and are performed for different reasons.

The easiest way to understand the difference is this:

LASIK changes the shape of your cornea.
Cataract surgery replaces the natural lens inside your eye.

What Does LASIK Do?

LASIK is a form of laser vision correction.

The cornea is the clear window at the very front of your eye. During LASIK, laser is used to permanently reshape corneal tissue so that light focuses differently inside the eye.

The natural lens of the eye remains in place.

LASIK is therefore performed primarily to correct a glasses prescription — such as myopia, hyperopia or astigmatism — rather than to treat a cataract.

What Does Cataract Surgery Do?

A cataract occurs when the natural lens inside your eye becomes cloudy.

During cataract surgery, we remove this cloudy natural lens and replace it with a clear artificial intraocular lens, or IOL.

So unlike LASIK, cataract surgery does not depend on reshaping the cornea to remove the cataract.

It replaces the lens that has become cloudy.

The new lens implant can also be selected to correct some of your existing prescription, which is why many patients find themselves less dependent on glasses after cataract surgery.

LASIK vs Cataract Surgery — The Simple Difference

LASIKCataract SurgeryWhere?Cornea at the front of the eyeNatural lens inside the eyeWhat happens?Corneal tissue is reshaped with laserCloudy natural lens is removedIs a lens implanted?NoYesTreats cataracts?NoYesCan correct prescription?YesYes, depending on the lens chosenNatural lens remains?YesNo — it is replaced by an IOL

If Cataract Surgery Can Correct My Prescription, Why Isn't It LASIK?

Because the way the prescription is corrected is completely different.

With LASIK, the focusing power of the eye is changed by altering the cornea.

With cataract surgery, we calculate the power of the new lens implant that will be placed inside your eye.

This is why the measurements before cataract surgery are so important.

We are not simply removing your cataract.

We are choosing the lens that you will see through afterwards.

Can I Have Cataract Surgery If I Have Had LASIK Before?

Yes.

But please tell your cataract surgeon that you have previously undergone LASIK, PRK or another form of laser vision correction.

Previous laser treatment changes the shape of the cornea, and this can make calculation of the power of your cataract lens implant more challenging.

If you still have records of your old prescription or previous laser treatment, bring them along if possible.

Will I Need LASIK After Cataract Surgery?

Not necessarily.

Before cataract surgery, we measure your eyes and choose an intraocular lens power according to the visual result we are trying to achieve.

Depending on your eyes and the type of lens selected, you may still require glasses for certain distances or activities afterwards.

I prefer to discuss these expectations before surgery so that we can decide what sort of vision matters most to you.