At the end of an ideal cataract surgery, you'll see clearly. To make that happen, you'll have the opportunity to choose the type of lens that sits inside your eye. But even with the right lens and the right surgeon, you could struggle with crisp vision after surgery if the surface of your eye is uneven.

Superficial keratectomy is the surgical removal of the eye's surface tissues. It's a quick procedure that's typically complete in a few minutes. (Learn more)

People who need this surgery before their cataracts are touched have eye health issues like nodular degeneration or band keratopathy. (Learn more)

But you might also want the surgery if you hope to use a multifocal lens in your cataract surgery or if you want tight control over how well you can see when the work is done. (Learn more)

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What Is the Surgery Like?

Cataract surgery is the replacement of the lens inside your eye. Superficial keratectomy is the removal of layers of tissue on the outside of your eye. Since the inside and the outside of your eye work together to give you clear vision, your doctor might choose to perform both procedures either at the same time or close together.

The American Academy of Ophthalmology says superficial keratectomy is over in 15 to 30 minutes. Your doctor will:

  • Sedate you. Drops to numb your eyes or general anesthetic to calm your whole body start the process.
  • Loosen. Alcohol or another agent helps to separate surface tissues from those that lie beneath.
  • Remove. A blade, brush, or laser polishes the cornea's surface.
  • Bandage. A contact lens covers the eye as it heals.

Who Might Need This Surgery?

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For some people, superficial keratectomy is an elective procedure, but for others, it's a critical part of preparing the eye for cataract surgery. These people have corneal health problems that will interfere with clear vision, even with the right lens.

Researchers writing for Review of Ophthalmology say these conditions typically call for superficial keratectomy before cataract surgery:

  • Anterior basement membrane dystrophy: People with this condition have tiny dots or specks in the cornea, and that leads to blurred or double vision. The speckles keep the cornea from sticking together, and as layers break apart, vision gets worse.
  • Band keratopathy: As the name implies, this condition involves a band of salts across the surface of the cornea. If this is a dense layer, it can cause significant vision loss.
  • Salzmann's nodular degeneration: People with this condition have blue/white nodes that pop up above the surface of the cornea. That leads to inadequate tear production and difficulties with contact lenses.

Even if your doctor puts the perfect lens inside your eye during cataract surgery, your cornea's problems will keep you from seeing clearly. By removing the abnormalities and smoothing the surface of the eye, your doctor ensures that you have the best chance at a successful cataract surgery.

In addition, these conditions can cause corneal tugging and thinning, and that increases your risk of problems during cataract surgery. Your doctor should correct the eye health problems before the operation starts so you won't have complications after surgery.

It's important to note that some types of eye health problems come back. In a study in the Canadian Journal of Ophthalmology, corneal health problems treated with superficial keratectomy came back in 24 percent of cases.

Studies like this indicate why follow-up care is so important when you have an eye health problem. Your doctor can help you learn how to maintain or control your eye health after surgery.

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Who Might Want This Surgery?

Some people need superficial keratectomy due to eye health problems, but others might want to consider the procedure to ensure that their cataract surgery goes as smoothly as possible.

For example, some people hope to use a multifocal lens to replace their clouded one. These new lenses have several different spots of focus of varying strengths, and in time, the brain learns to use that varying magnification power. With these lenses, people have a smaller chance of needing glasses or contacts.

These are powerful tools, but they're also very precise. To make sure you have the right strength and power of lens, your doctor must make very delicate measurements of your eyes. Superficial keratectomy can remove minor abnormalities, so your doctor can make the most accurate lens choice for you.

Researchers writing for Ocular Surgery News also point out that superficial keratectomy can improve vision and reduce the need for correction. People with significant vision problems might appreciate a touch of correction before cataract surgery, so they don't need a significantly strong lens implanted.

People who dislike risks and want control can benefit from superficial keratectomy, as the results of cataract surgery are just more predictable when the two procedures are combined. But doctors can help to make the right decision. You don't have to decide alone whether this is the right step for you to take. Your doctor can steer you in the right direction.


How Is Corneal Scraping Surgery Performed? (August 2016). American Academy of Ophthalmology.

Smooth Operator. (October 2013). Review of Ophthalmology.

Cataract Surgery in Eyes With Compromised Corneas. (January 2016). EyeWorld.

Optimize Cataract Surgery Outcomes by Addressing Corneal Pathology. (September 2015). Ocular Surgery News.

Superficial Keratectomy: Indications and Outcomes. (December 2018). Canadian Journal of Ophthalmology.