Understanding Traditional Glaucoma Surgery
Traditional glaucoma surgery refers to incisional procedures designed to lower eye pressure when other treatments have not provided enough relief. Glaucoma is a group of eye diseases that damages the optic nerve, which is the nerve that sends visual information from your eye to your brain. This damage is most often caused by elevated intraocular pressure, or pressure inside the eye. When left unmanaged, glaucoma can lead to gradual and irreversible vision loss.
More than 3 million Americans have glaucoma, but only half are aware of their condition (Glaucoma Research Foundation, 2023). Because vision loss from glaucoma typically happens slowly, many people do not notice changes until the disease has progressed. Traditional surgery plays an important role in protecting remaining vision for patients whose glaucoma has not responded well enough to eye drops, laser treatments, or minimally invasive glaucoma surgery, often called MIGS.
Eye drops work by either reducing the amount of fluid your eye produces or helping fluid drain more efficiently. Laser procedures use focused light energy to improve the eye's natural drainage system. MIGS procedures involve tiny devices or small openings created through very small incisions. These approaches work well for many patients, especially those with mild or early glaucoma.
Traditional glaucoma surgery is more involved than these other options. The incisions are larger, and the procedures create new drainage pathways or place small devices to redirect fluid out of the eye. Because of this, traditional surgery can achieve a greater and more sustained drop in eye pressure. This makes it a strong choice for patients with moderate to advanced glaucoma who need a more powerful intervention to protect their vision.
Traditional glaucoma surgeries have been performed for decades. Surgeons around the world have extensive experience with these procedures, and long-term studies have shown their effectiveness in lowering eye pressure and slowing the progression of glaucoma. While the recovery period is longer than what patients experience with MIGS, the pressure-lowering results tend to be more significant and longer lasting. Your glaucoma specialist can help you understand whether traditional surgery is the right step based on your specific condition.
Best Suited for These Situations
Traditional surgery is most often recommended for patients whose glaucoma has progressed beyond the early stages. If your optic nerve has already sustained noticeable damage or your visual field tests show areas of vision loss, a stronger approach to lowering eye pressure may be needed. Traditional surgery can achieve the level of pressure reduction required to slow further damage in these more advanced cases.
Many patients begin glaucoma treatment with one or more types of prescription eye drops. Over time, some patients find that their eye pressure remains too high even when using multiple medications. Others may experience side effects from their drops that make long-term use difficult. Traditional surgery offers an alternative that can reduce or even eliminate the need for daily eye drop use in some cases.
Laser treatments and MIGS procedures are excellent first-line options for many patients. However, they may not lower pressure enough for patients with more aggressive or advanced disease. If you have already had a laser procedure or a MIGS procedure and your eye pressure is still above your target level, traditional surgery may be the next logical step in your treatment plan.
In some situations, a patient's eye pressure is high enough that their remaining vision is at significant risk. Traditional surgery can provide a substantial and relatively rapid drop in pressure, which helps protect the optic nerve from further harm. Your surgeon will evaluate the urgency of your situation and recommend the approach most likely to preserve your vision.
Who Is a Good Candidate
You may be a good candidate for traditional glaucoma surgery if your intraocular pressure remains above your target despite using medications, laser therapy, or MIGS. Your target pressure is the level your doctor believes is low enough to prevent additional optic nerve damage. This number is different for every patient and depends on the severity of your glaucoma and other individual factors.
Some patients struggle to use their eye drops consistently. This may be due to physical challenges like arthritis, difficulty remembering multiple daily doses, or side effects such as eye redness, irritation, or fatigue. If maintaining a reliable eye drop routine is a barrier to managing your glaucoma, surgery may offer a way to lower pressure without relying as heavily on daily medications.
If your visual field tests or optic nerve imaging show that your glaucoma is getting worse over time, even with treatment, your doctor may recommend traditional surgery. The goal is to achieve a lower and more stable eye pressure that can help slow or halt further vision loss. Patients who show signs of progression despite current treatment are often strong candidates for a more definitive surgical approach.
Good candidates for traditional glaucoma surgery generally have eyes that are otherwise healthy enough to undergo and heal from the procedure. Your surgeon will review your full eye health history, including any previous eye surgeries, conditions affecting the surface of the eye, and the overall structure of your eye. Certain conditions may influence which type of traditional surgery is best for you.
Your surgeon will consider several factors before recommending traditional surgery. These include the type and stage of your glaucoma, your current medications, your eye anatomy, and any previous procedures you have had. Certain health conditions, such as bleeding disorders or active eye infections, may require treatment before surgery can be scheduled. An honest conversation with your glaucoma specialist is the best way to find out if surgery is right for you.
How Traditional Glaucoma Surgery Works
Your eye constantly produces a clear fluid called aqueous humor. This fluid nourishes the front part of your eye and then drains out through a small area called the trabecular meshwork, which acts like a tiny filter. In a healthy eye, the amount of fluid produced and the amount that drains out are balanced, keeping pressure at a safe level. In glaucoma, this drainage system does not work properly. Fluid builds up, pressure rises, and the optic nerve can become damaged over time.
Traditional glaucoma surgery works by creating a new route for fluid to leave the eye. Instead of relying on the eye's natural drainage system, the surgeon either creates an opening in the eye wall or places a small tube to redirect fluid to a space just beneath the surface tissue of the eye. This area is called the subconjunctival space. The conjunctiva is the thin, clear tissue that covers the white part of your eye. Once fluid reaches this space, it is absorbed by nearby blood vessels and tissues, which effectively lowers the pressure inside the eye.
Traditional glaucoma surgery is typically performed in an outpatient surgical center, meaning you go home the same day. The procedure is done under local anesthesia, so you will be awake but your eye will be completely numb. You may also receive light sedation to help you relax. The surgeon uses a specialized microscope to see the tiny structures of your eye during the operation. The entire procedure usually takes between thirty minutes and one hour, depending on the type of surgery being performed.
During surgery, the surgeon carefully opens the outer layers of the eye to access the area where fluid needs to be redirected. Depending on the technique used, this may involve creating a small flap in the sclera (the white part of your eye), placing a tiny tube connected to a drainage plate, or a combination of both. Fine sutures, or stitches, are placed to close the surgical site and control the rate at which fluid drains. The precise details vary based on which type of surgery is chosen, which your surgeon will explain to you in advance.
Types of Traditional Glaucoma Surgery
Trabeculectomy is one of the most well-established glaucoma surgeries. During this procedure, the surgeon creates a small flap in the sclera and removes a tiny piece of the trabecular meshwork. This creates a new channel for aqueous humor to flow out of the eye. The fluid collects under the conjunctiva in a small, raised area called a filtering bleb. The bleb is usually located under the upper eyelid, so it is not visible to others. Over time, the fluid in the bleb is absorbed by surrounding tissues, keeping eye pressure low.
Trabeculectomy has a long history of success and can produce very low eye pressures when the surgery heals well. Your surgeon may apply a medication to the surgical site during the procedure to help prevent scarring, which is the most common reason a trabeculectomy may need follow-up adjustments. This surgery is often chosen for patients who need a substantial reduction in eye pressure and who have not had previous surgeries on the same part of the eye.
Tube shunt surgery, also known as drainage implant surgery or aqueous shunt surgery, involves placing a small silicone tube inside the eye. The tube is connected to a tiny plate that sits on the outside surface of the eye, beneath the conjunctiva. Fluid flows through the tube to the plate, where it is absorbed by the body's tissues. The plate creates a reservoir area that helps manage fluid drainage over the long term.
Tube shunt surgery is often recommended for patients who have had a previous trabeculectomy that did not maintain adequate pressure control, or for those whose eyes may not respond well to trabeculectomy due to scarring from prior surgeries or certain types of glaucoma. It is also a good option for patients with specific conditions such as neovascular glaucoma, in which abnormal blood vessels grow in the drainage area, or uveitic glaucoma, which is glaucoma caused by inflammation inside the eye.
Both trabeculectomy and tube shunt surgery are effective at lowering eye pressure and have been studied extensively over many years. Your surgeon will recommend one over the other based on your individual circumstances. Here are some general differences between the two procedures.
- Trabeculectomy may achieve slightly lower eye pressures in some cases, especially in eyes that have not had previous surgery
- Tube shunt surgery may be preferred when there is significant scarring from prior procedures or when certain types of glaucoma are present
- Both surgeries require a period of careful follow-up to monitor healing and adjust treatment as needed
- The choice between the two depends on your glaucoma type, your eye's surgical history, and your surgeon's clinical judgment
Deciding which type of traditional surgery is best is a decision you and your glaucoma specialist will make together. Your doctor will evaluate the specific characteristics of your glaucoma, the anatomy of your eye, any previous treatments or surgeries you have had, and your overall health. Open-angle glaucoma accounts for 90% of all glaucoma cases in the United States (National Eye Institute, 2023), and both trabeculectomy and tube shunt surgery are well-suited for this common form of the disease. Your surgeon will take the time to explain why a particular approach is recommended and will answer all of your questions before proceeding.
What to Expect Before, During, and After Surgery
Before your procedure, you will have a thorough preoperative evaluation. This includes detailed measurements of your eye pressure, imaging of your optic nerve, and visual field testing to document your current level of vision. Your surgeon will review all of your medications, including eye drops, and give you specific instructions about which medications to continue and which to stop before surgery. You will also receive instructions about eating and drinking before your procedure.
Plan to have someone drive you to and from the surgical center on the day of your operation. Wear comfortable clothing and avoid wearing eye makeup or perfume. Your surgical team will provide you with a clear list of steps to follow in the days leading up to your procedure.
When you arrive at the surgical center, the staff will prepare you for the operation. Eye drops will be used to dilate your pupil and numb the surface of your eye. You may receive additional numbing medication through a small injection near the eye. Light sedation is often provided through an intravenous line to help you feel calm and comfortable. You will be awake during the surgery, but you should not feel pain. You may see bright lights or feel gentle pressure, which is normal.
The surgery itself typically lasts between thirty and sixty minutes. Your surgeon will work carefully under a microscope, and the surgical team will monitor your comfort throughout the procedure. When the surgery is complete, a protective shield will be placed over your eye.
After surgery, you will rest briefly in a recovery area before going home. You will need to wear a protective eye shield, especially while sleeping, for the first week or two. Your surgeon will prescribe eye drops to prevent infection and control inflammation. It is normal to experience some mild discomfort, redness, tearing, or blurry vision in the days following surgery. These symptoms typically improve as your eye heals.
During the first week, avoid the following activities to protect your eye.
- Rubbing or pressing on the operated eye
- Bending over at the waist or lifting heavy objects
- Strenuous exercise or activities that could jar the head
- Swimming, hot tubs, or getting water directly in the eye
- Wearing eye makeup on or near the operated eye
Recovery from traditional glaucoma surgery takes longer than recovery from MIGS or laser procedures. Most patients notice gradual improvement in comfort and vision over several weeks. Your eye pressure may fluctuate during the healing period, which is expected. Your surgeon will monitor your progress closely, often scheduling follow-up visits weekly or even more frequently during the first month.
Full healing typically takes six to eight weeks, though some patients may take longer. During this time, your surgeon may adjust your eye drop medications, remove or adjust sutures, or perform minor in-office procedures to help your eye heal properly. It is important to attend all follow-up appointments, even if you feel your eye is doing well.
Once your eye has fully healed, your surgeon will assess the success of the surgery by measuring your eye pressure, evaluating the surgical site, and checking your optic nerve and visual field. Many patients achieve significantly lower eye pressure after traditional surgery, and some are able to reduce or discontinue their glaucoma eye drops. However, glaucoma is a lifelong condition that requires ongoing monitoring. You will continue to have regular check-ups with your glaucoma specialist to ensure your eye pressure remains at a safe level and to detect any changes early.
Your Journey at Washington Eye Institute
Your journey begins with a comprehensive evaluation by a glaucoma specialist at Washington Eye Institute. During this visit, your doctor will perform a thorough examination of your eyes, review your medical and eye health history, and discuss the treatments you have tried so far. Advanced diagnostic testing will help your surgeon understand the extent of your glaucoma and determine whether traditional surgery is the right next step for you.
After your evaluation, your surgeon will sit down with you to discuss the findings and explain your options. If traditional surgery is recommended, your doctor will explain which procedure is best suited for your eyes and why. You will have the opportunity to ask questions, voice any concerns, and make sure you feel comfortable with the plan before moving forward. Your care team will provide written materials and detailed instructions so you know exactly what to expect.
On the day of your surgery, you will be welcomed by a supportive team dedicated to making your experience as smooth and comfortable as possible. Every member of the surgical team is focused on your safety and well-being. The facility is equipped with modern surgical technology, and your glaucoma surgeon has extensive training and experience in traditional glaucoma procedures. From the moment you arrive until you are ready to go home, you will be guided through each step of the process.
After your surgery, the team at Washington Eye Institute will stay closely involved in your recovery. Frequent follow-up visits allow your surgeon to monitor your healing, make any necessary adjustments, and ensure the best possible outcome. Your care team is available to answer questions and address concerns that may arise during your recovery period. The goal is to help you achieve stable, healthy eye pressure so that your remaining vision is protected for years to come.
Managing glaucoma is a lifelong commitment, and the team at Washington Eye Institute is here to support you every step of the way. Even after your eye has healed from surgery, regular monitoring remains essential. Your glaucoma specialist will continue to track your eye pressure, assess your optic nerve health, and update your treatment plan as needed. You are not alone on this journey, and your care team is dedicated to helping you maintain the best possible quality of vision.
Questions and Answers About Traditional Glaucoma Surgery
Both trabeculectomy and tube shunt surgery are designed to create a new drainage pathway that bypasses the eye's natural, damaged drainage system. This allows fluid to leave the eye more efficiently, resulting in a meaningful reduction in intraocular pressure. The amount of pressure lowering varies from patient to patient, but many people experience a substantial improvement. Your surgeon will discuss realistic expectations for pressure reduction based on your individual situation.
Unlike MIGS procedures, which may have a recovery period of just a few days, traditional glaucoma surgery requires a longer healing timeline. Most patients need six to eight weeks for full recovery. During this time, you will use prescription eye drops and attend frequent follow-up appointments. Some discomfort, blurry vision, and redness are normal in the early days, but these symptoms gradually improve. Your surgical team will provide clear guidance on activity restrictions and what to watch for during your recovery.
As with any surgical procedure, traditional glaucoma surgery carries some risks. These may include infection, bleeding, eye pressure that is too low or too high, changes in vision, and the need for additional procedures. Scarring at the surgical site is one of the most common challenges and can sometimes reduce the effectiveness of the surgery over time. Your surgeon will discuss these risks with you in detail before your procedure, and steps are taken during surgery and follow-up to minimize them. Most patients have successful outcomes, and the benefits of controlling eye pressure typically outweigh the risks for candidates who need this level of treatment.
One of the goals of traditional glaucoma surgery is to lower eye pressure enough that fewer medications are needed. Some patients are able to stop using one or more of their glaucoma eye drops after surgery, while others may still need a reduced regimen. The outcome depends on factors such as the severity of your glaucoma, how your eye heals, and your target pressure. Your surgeon will work with you after surgery to adjust your medications based on your results.
MIGS procedures are designed to offer a mild to moderate reduction in eye pressure with a shorter recovery time and fewer risks. They are best suited for patients with mild to moderate glaucoma. Traditional surgery, on the other hand, can achieve greater and more sustained pressure reduction. It is typically reserved for patients with more advanced disease or those who have not achieved adequate results with less invasive approaches. Your glaucoma specialist will help determine which type of surgery best fits your needs.
Feeling nervous before eye surgery is very common. The team at Washington Eye Institute understands this and is committed to helping you feel informed, prepared, and supported throughout the process. You are encouraged to ask as many questions as you need during your consultation and preoperative visits. Knowing what to expect can help ease anxiety. On the day of surgery, the staff will explain each step as it happens, and sedation is available to help you feel relaxed. Your comfort and confidence are a priority at every stage of your care.