Glaucoma is treated by lowering intraocular pressure, and this can be achieved with laser surgery, medications, conventional (“incisional”) surgery, or a combination of these. Treatment plans can differ depending on the type of glaucoma and the individual patient. Treatment options are organized below by glaucoma type.
SELECTIVE LASER TRABECULOPLASTY (SLT)
Selective laser trabeculoplasty (SLT), often a first-line treatment for Open-Angle Glaucoma, can also be effective in patients already on eye drops. SLT uses low levels of laser light to improve drainage of intraocular fluid through the natural drainage pathway out of the eye. For most eyes this improved drainage helps lower eye pressure and a single treatment’s effect lasts 2 to 3 years, and sometimes longer. Since SLT leaves the drainage canals intact, it can be repeated if the initial treatment was effective. Minor self-limited inflammation follows SLT and may aid in the eye pressure lowering effect.
Some patients can have their eye pressure controlled with SLT alone. Others require glaucoma medications also or incisional surgery in the operating room.
What to expect:
• SLT is performed in an outpatient setting, frequently in the doctor’s office.
• Your doctor will use special eye drops to numb your eye. Then, your doctor will have you sit at the laser and place a special lens with contact lens gel on your eye to help direct the laser light onto the drainage canals in your eye.
• You will hear a series of clicks and see bright lights, like a camera flash, as your doctor performs the procedure. You may feel a slight tingling sensation, but the procedure is nearly painless.
• SLT takes about 5-10 minutes.
• At the end of the treatment, the lens is removed and your vision will be blurry until the thick contact lens gel is rinsed off.
• After the treatment, you should take it easy for a day and then return to your daily routine.
Open-Angle Glaucoma is often treated with medications that either help the eye’s fluid drain better or decrease the amount of fluid being made. Medications must be taken daily to keep eye pressure at a safe level. In most cases, medications can safely control eye pressure for many years.
It is normal for your medication prescriptions to change over time. Changing medications does not necessarily mean that your glaucoma is getting worse. As your body begins to develop a tolerance for a medication, it may slowly lose its effectiveness and may need to be replaced by a stronger version of the same drug or a different medication. Doctors often can return to previously used medications after your body has had a chance to “forget” the old medication.
Glaucoma medications most commonly are in the form of eye drops. put drops in your eye correctly.
Most medications have some side effects, including effects on vision, eye comfort, and sometimes other parts of your body. In particular, older people with glaucoma should look for changes in behavior or mobility that may be a side effect of medications. If the side effects are very uncomfortable or last a while, your doctor may be able to prescribe a different medication.
To make sure your glaucoma medications are not interacting with other medications you are taking, make sure to tell all of your doctors, including your family physician, about your glaucoma medications and any other drugs you may be taking, including aspirin, vitamins and natural remedies. Tell your doctors about any side effects you may be experiencing or allergies you have.
The following are some of the possible side effects of the main classes of glaucoma medications:
• Prostaglandin Analogs
Eye color change, darkening of eyelid skin, eyelash growth, droopy eyelids, sunken eyes, stinging, eye redness, and itching
• Beta Blockers
Low blood pressure, slowed pulse rate, fatigue, shortness of breath
• Alpha Agonists
Burning or stinging, fatigue, headache, drowsiness, dry mouth and nose, allergic reaction
• Carbonic Anhydrase Inhibitors
In eye drop form—stinging, burning, eye discomfort; in pill form—tingling hands and feet, fatigue, stomach upset, memory problems, frequent urination
• Rho Kinase Inhibitors
Eye redness, deposits on cornea, stinging, small bleeds on the white of the eye
New Treatments on the Horizon
New forms of glaucoma drug delivery are being developed to improve medication treatment options. One area of interest is “sustained-release” medication. Sustained-release medication evenly releases a drug over a longer time. In this way, medications can be used weekly, monthly, or at even longer intervals. This would make the process of taking medications more convenient and efficient and potentially reduce side effects. There are many sustained-release options being researched and developed.
In addition, new classes of drugs to treat glaucoma are being studied. Researchers are working to find glaucoma medications with fewer side effects, ones that can be taken less often, and drugs that are more responsive to the eye and so more effective at lowering eye pressure.
When SLT, glaucoma medications, and other treatments do not lower eye pressure to the desired level, your doctor may recommend some form of incisional surgery. This surgery is done in a hospital or surgery center, using a microscope and microsurgery instruments, and includes making a cut (incision) in the eye.
What to expect:
• Before surgery begins, a local anesthetic along with a medication to help you relax is given to prevent you from feeling any discomfort during the procedure.
• During surgery, the doctor looks through a microscope that is placed several inches above your eye.
• Eye surgery does require some recovery time, which will vary according to your age, daily activities, and other personal factors. Most people can move around and return to their normal activities soon after going home, though you may have to wear an eye patch to protect your eye.
• For at least a week after glaucoma surgery, it is advisable to keep water out of the eye. It is also good to take a break from driving, reading, bending, and strenuous exercise.
• Glaucoma surgery may have to be repeated, especially if excessive scarring cannot be prevented or after long periods of time.
Minimally Invasive Glaucoma Surgery (MIGS)
Minimally Invasive Glaucoma Surgery (MIGS) procedures have been developed in recent years to treat patients earlier and more safely than conventional surgery. As with all new procedures, multi-year follow-up studies are required to see which ones will remain useful long-term.
MIGS procedures include microsurgical instruments and devices and smaller incisions that manipulate the eye tissues less and therefore reduce the risk of complications. The increased safety of these surgeries is traded for reduced effectiveness.
MIGS procedures and devices may work in a number of ways. Some enhance fluid outflow within the eye’s drainage system, some carry fluid to the outside of the eye. Some types of MIGS procedures are to be done only with cataract surgery, whereas other MIGS procedures can be performed independent of cataract surgery.
Cataract surgery alone lowers pressure, and the combination of a MIGS surgery and cataract surgery can lower pressure more to help reduce the need for medication. Implanting a MIGS device adds a few minutes to cataract surgery.
The MIGS group of devices and surgeries are divided into categories according to how they work:
• Miniaturized versions of trabeculectomy: In these procedures, tiny tubes are inserted into the eye to help drain fluid from inside the eye to underneath the outer membrane of the eye (conjunctiva). For example, the FDA cleared XEN Gel Stent and the PRESERFLO (formerly InnFocus) MicroShunt which is cleared outside the US.
• Angle-based surgeries: In these procedures, specialized instruments and devices are used to modify the eye’s drainage canals (trabecular meshwork, Schlemm’s canal, and collector channels) and improve the drainage of fluid from the eye. These procedures involve cutting through the trabecular meshwork (e.g., Trabectome, Kahook Dual Blade, OMNI Surgical System), bypassing the trabecular meshwork by placing a stent in the Schlemm’s canal (e.g., iStent Inject, Hydrus Microstent), and expanding the Schlemm’s canal and collector channels with a gel (e.g., iTrack, OMNI Surgical System). Different angle-based MIGS procedures can be combined in various ways in order to increase drainage of fluid from the eye.
Conventional surgeries for glaucoma include trabeculectomy or aqueous shunts (see below). While they can be more effective at lowering eye pressure and preventing progression of glaucoma, they also have more potential complications.
In this procedure, a tiny opening is made in the sclera (the white part of the eye) with a small surgical instrument. This new opening allows the intraocular fluid to bypass the clogged drainage canals and directly flow out of this new opening. Special medications (“antifibrotics”) may be used to prevent scarring and closure of the new opening. The opening is covered by conjunctiva creating a bleb on the sclera. This procedure requires stitches and the recovery period is usually a few weeks.
Aqueous Shunt Surgery
During aqueous shunt surgery, a tiny tube is implanted that drains fluid out of the eye. Like trabeculectomy, this conventional surgery also requires stitches and the recovery period is usually a few weeks.
There are many unapproved treatments that are promoted on the internet and elsewhere, including marijuana/cannabidiol (CBD), stem cells, herbal medicines, and nutritional supplements. These treatments are not part of the standard of care in glaucoma treatment and may negatively impact your current treatment. You should discuss any additional treatments you are considering with your doctor before starting them.
Treatment of Angle-Closure Glaucoma and eyes at risk for this disease usually involves a laser procedure, laser peripheral iridotomy, to create a small opening in the outer edge of the iris.
If you have Angle-Closure Glaucoma in one eye, your doctor may treat the other eye as a safety measure.
Other treatments are similar to those for Open-Angle Glaucoma and include medications to lower eye pressure, trabeculectomy or tube shunt surgery, and, rarely, Selective Laser Trabeculoplasty. To learn more about these treatments, see the corresponding sections for Open-Angle Glaucoma in the Treating Glaucoma section (above).
Cataract surgery has also been shown to help in the treatment of Primary Angle-Closure Glaucoma. Removing the cataract opens the angle and usually has a favorable effect on the eye pressure.
Treatment of Normal-Tension Glaucoma
Treatment of Pigmentary Glaucoma
The treatment of Pigmentary Glaucoma involves lowering eye pressure using medications, laser treatments, or surgery. Unfortunately, it is difficult to reduce or eliminate the release of iris pigment. Therefore, attention is focused on reducing eye pressure.
Treatment of Congenital Glaucoma
Both medication and surgery are used to treat Congenital Glaucoma. Medications can be in the form of eye drops, pills, or liquids to be taken by mouth. Laser surgery also may be used.
These treatments help to either decrease the amount of fluid made in the eye or increase the amount of fluid out of the eye to lower eye pressure. Surgical procedures that are used to help control eye pressure in Congenital Glaucoma include filtering surgery, aqueous shunt surgery, and goniosurgery, a special procedure that opens canals in the trabecular meshwork. It is sometimes necessary to repeat glaucoma surgery in order to successfully control eye pressure.
Treatment of Exfoliative Glaucoma
Generally, this kind of glaucoma is more difficult to control with medication. Patients with Exfoliative Glaucoma often require a more aggressive, stepwise treatment plan and more often need laser treatment or surgery. Often more frequent visits to their eye doctor are necessary to monitor for disease progression.
Treatment of Neovascular Glaucoma
Treatments for Neovascular Glaucoma often involve decreasing the growth of blood vessels. These treatments include laser treatment to the retina and anti-VEGF drugs which lead to regression of abnormal blood vessels in the eye. Medications used for Open-Angle Glaucoma may be used also, as well as surgery that includes trabeculectomy and drainage implant procedures.
Treatment of Uveitic Glaucoma
To treat elevated eye pressure in Uveitic Glaucoma, doctors use many of the same eye pressure-lowering medications as those used for Open-Angle Glaucoma. Laser treatments typically are not used because they can cause more inflammation. In cases that cannot be controlled with medication, surgical treatment may involve an aqueous shunt. In addition to treatment by an eye doctor, sometimes a rheumatologist will prescribe medication to treat the root cause of the inflammation.
Treatment of Traumatic Glaucoma
The treatment of Traumatic Glaucoma varies depending on when glaucoma develops and the type of eye injury. When glaucoma occurs years after an eye injury, the treatment is similar to Open-Angle Glaucoma except that SLT is usually not effective. When glaucoma develops immediately after eye injury, the treatment is mainly guided by the type of trauma and the extent of damage to the eye.