Goniotomy

What is goniotomy?

Goniotomy is a type of microinvasive glaucoma surgery (MIGS) that improves how fluid flows through and out of your eyes. “Microinvasive” means it uses extremely small, precise tools and techniques inside your eye. This type of eye surgery can help prevent permanent eye damage and vision loss from conditions that cause too much pressure inside your eyes.

What does goniotomy treat?

Goniotomy (pronounced “go-nee-AHT-oh-me”) is a treatment for multiple forms of glaucoma. Glaucoma is a condition that happens when the pressure inside your eye (intraocular pressure) is too high. In years past, goniotomy was mainly for treating congenital glaucoma in children (“congenital” means you have it when you’re born). But eye surgeons are now using it more frequently for adults with glaucoma, too.

High pressure inside your eye can cause permanent damage, vision loss and even total blindness. Glaucoma happens faster when the pressure inside your eye rises suddenly, and the damage is usually worse when glaucoma lasts longer or involves higher pressures.

A goniotomy can lower eye pressure, helping prevent damage from happening or getting worse. But it can’t reverse retina or optic nerve damage once they happen.

How should I prepare for a goniotomy?

Your eye care specialist will talk to you before your surgery about how to prepare. Some of the things they’ll discuss with you include:

• Medications. If you take any medications, your eye surgeon will review them with you. Make sure to tell them about every medication you take, including any vitamins, herbs, supplements, etc. Your surgeon will let you know which medications to keep taking, which to stop and how to stop taking any safely.
• Anesthesia. There are a few different ways to prevent pain or discomfort during goniotomy. Your surgeon and/or an anesthesiologist will talk to you about the options.
• Fasting. Your surgeon may advise you not to eat anything starting eight or so hours before your surgery, and not to drink anything other than clear liquids fewer than two hours before surgery. At two hours before surgery, you’ll need to avoid liquids entirely.

What happens during goniotomy?

At the start of a goniotomy procedure, your eye surgeon or anesthesiologist will give you medication to prevent any pain during the surgery. If you receive general anesthesia, it’ll be through an intravenous (IV) line inserted into a vein somewhere on your body (usually your arm or hand).

When everything is ready, your eye surgeon will make a small opening on the cornea of your eye. They’ll use it to insert special tools into the anterior chamber (“anterior” means “front”), the liquid-filled space just behind your cornea.

After the surgical tool is inside your eye, your surgeon will place a gonioscopic lens on the surface of your eye. These strong lenses need to touch your eyes to have maximum clarity. They let your surgeon see a magnified view inside your eye. 

Now that your surgeon can see inside your eye, they’ll maneuver them around carefully to where your iris and sclera meet. There’s a band of tissue called the trabecular meshwork, and it goes all the way around your iris. Your eye surgeon will make cuts in that meshwork tissue, allowing more aqueous humor fluid to flow through it.

When your surgeon finishes making those cuts (and if you aren’t having any other eye procedures done at the same time), they’ll withdraw the surgical tool(s) from your eye. They’ll then give you a small, clear eye shield to wear. That shield keeps things from touching your eye, especially while you’re asleep.

How long does a goniotomy take?

A goniotomy should take under 15 minutes. That doesn’t include prep time before the surgery and a monitoring period (if necessary) after the surgery. The procedure may also take longer if your eye surgeon is doing another procedure like cataract surgery along with your goniotomy (which is very common). Your eye surgeon is the best source of information about what kind of timeframe you can expect for your surgery. 

What happens after a goniotomy?

Your eye surgeon may need you to stay after surgery for a short monitoring period. After that, you can go home. You’ll need someone to drive you because you shouldn’t drive after this surgery until your eye surgeon clears you to do so.

After a goniotomy, your eye surgeon will prescribe medicated drops for your eyes. You’ll only need to take some of these medications, like antibiotics, for a few days, but others, like anti-inflammatory drugs, you’ll need to take for weeks or even a month.

Recovery from this surgery shouldn’t be painful. Most people only need over-the-counter painkillers like acetaminophen. Slight eye-watering, blurred vision, minor discomfort or soreness, or a feeling like you have sand or dust in your eye are normal and should stop within a few days.

Your eye surgeon will also schedule regular follow-up visits. Your first follow-up visit will be the day after your surgery. Your eye surgeon will check the pressure inside your eye and make sure it’s not too high or too low. They’ll also look for any signs of complications and ask how your eyes feel and about any other symptoms you might be experiencing.

What are the benefits of goniotomy?

A goniotomy has several key benefits that make it a good option for treating different types of glaucoma. Those benefits include:

• Decades of research to support it. Almost 90 years of research and analysis support goniotomy’s ongoing use.
• It’s safe. Even with decades of history and research, the techniques for goniotomy haven’t changed much. Serious complications are also rare.
• It’s effective. Success rates for this procedure range from 70% to 90%, depending on the specific condition it’s treating and the age group of the person having this surgery.
• It’s an earlier option than other treatments. Other treatments aren’t helpful until the pressure inside your eye is higher.
• The technique is adjustable. The incision lengths can vary from person to person, depending on their specific case and needs.

What are some drawbacks of a goniotomy or reasons why it might not be helpful for me?

You shouldn’t have a goniotomy if any of the following conditions or circumstances apply to you:

• Angle-closure glaucoma.
• Thyroid eye disease.
• Increased bleeding risk (like taking blood thinners).
• People who have frequent, sharp eye pressure increases, like people whose jobs or hobbies involve heavy lifting, may need to pause those activities for one or several weeks after surgery.

What are the risks or complications of goniotomy?

Serious complications from goniotomy are rare. Some of the complications are general and can happen with any eye surgery. Examples of those include eye pain or eye infection. The type of anesthesia you receive can also make anesthesia complications possible, but this is also rare. 

Other complications are more specific to this procedure. Some examples of those include:

• Refractive errors like astigmatism.
• Larger amounts of bleeding inside your eye (small amounts of bleeding are common and usually go away on their own within a week or two).
• Detachment of your retina or the layer underneath it, the choroid.
• “Rebound” pressure increases.
• Cloudy vision (like with cataracts, which are treatable with follow-up procedures).
• Low pressure inside your eye (hypotony), though this is rare.

What is the recovery time after a goniotomy?

The surface of your cornea should heal very quickly after a goniotomy, usually within a few days. And vision typically returns about that fast, too. The rest of your recovery should take about six weeks, until your eye specialist can determine if the procedure lowered your eye pressure. Some people may need up to a few months to recover.

Other factors can also affect your expected recovery time. Your eye surgeon can tell you what kind of recovery time you should expect. That includes when you can return to your regular activities like driving, school, work and hobbies.

Dos and don’ts of goniotomy recovery

While you’re recovering, there are several things you should remember.

Until your eye surgeon tells you otherwise, AVOID:

• Touching or rubbing your eyes (bathing and washing your face are OK, but be cautious when cleaning your eyelid or areas around your eye).
• Using eye makeup of any kind.
• Touching your eye with any part of the bottle while putting drops in your eyes.
• Bending over or kneeling.
• Lifting of any kind (your eye surgeon can tell you a specific weight limit for lifting).
• Strenuous exercise of any kind, including running or swimming.
• Sex.

Some things you should remember to do include:

• Wash your hands, especially before putting drops or medication in your eye.
• Your eye may be light sensitive in bright light, so you may wear sunglasses for comfort.
• Take medications exactly as prescribed.

What kinds of follow-up will I need?

Your eye care specialist will also want to continue monitoring for several months after your surgery. Those visits are critical for avoiding complications and making sure your surgery is effective. It’s crucial that you go to these visits, even if you don’t notice any changes or issues in your vision or how your eyes feel.

When should I call my healthcare provider?

You should schedule an appointment with your eye specialist if you experience the following after a goniotomy:

• Blurry vision.
• More glare during the daytime.
• Diffraction stars on lights, especially at night or in dim environments (that means lights look like they have points instead of being perfectly round).

When do I need emergency care?

There are a few things that mean you need emergency medical care after a goniotomy. Even if it’s been several months since your surgery, you should go to the hospital if you experience the following:

• Any eye pain.
• Any sudden vision loss, especially in the center of your field of view.
• Haloes or rings around lights.
• Eye redness and/or oozing (like pus or discharge).