What Is Glaucoma, and How Can It Be Treated?
What is Glaucoma?
Glaucoma is an eye disease in which increased pressure in your eye or eyes causes damage to the optic nerve. It can be a scary diagnosis, as the damage done by glaucoma can’t be reversed. Sufferers will need some kind of treatment for the rest of their lives.
What are the Symptoms of Glaucoma?
There are two kinds of glaucoma. Open-angle glaucoma, which is caused by a partial blockage of the normal drainage of fluid from the eye, causes patchy blind spots and advances to tunnel vision; that is to say, significant loss of peripheral vision. Angle-closure glaucoma causes headaches, pain in the eyes, nausea, and vomiting, blurred vision, and halos around lights. These symptoms can sometimes be mistaken for migraine. The eyes may also become red. These symptoms coming on suddenly are a medical emergency. If you have them and have no history of migraine, you should go to the ER.
Glaucoma tends to run in families. Glaucoma treatment generally includes medications and possibly surgery.
How Will the Doctor Diagnose Glaucoma?
The primary test for glaucoma risk has the fancy name of tonometry. One form of tonometry is the test the eye doctor does where you look into a device and a puff of air is pushed into your eyes. This test gives the doctor a quick idea as to whether your eye pressure is high and further testing is needed. Tonometry is a basic screening test, however, and on its own is not sufficient for a diagnosis. If this test shows high pressure, the doctor may order a more sensitive form of tonometry in which they numb your eyes with eye drops and gently touch your cornea with a tonometer.
To finalize a diagnosis, the doctor will also look inside your eye with a magnifying lens, use a test called a gonioscope to examine the angle between the cornea and iris (this helps determine what kind of glaucoma you have), and do a visual field test to look for vision damage.
What is the First Line of Treatment?
You might have heard that glaucoma is treated with surgery. This is true, but except for acute angle-closure glaucoma, surgery is not the first resort. Instead, most patients are prescribed eye drops that either decrease the amount of fluid produced in your eyes or improve drainage, depending. In some cases, you might have to use more than one eye drop or try different ones to get a good result. Here are the eye drops that are generally used.
To reduce fluid production:
Beta blockers. Not quite the same thing as the psych medication. They are reasonably inexpensive but can have systemic side effects if the eye is not closed right after application. Side effects can include difficulty breathing, slowed heart rate, lower blood pressure, fatigue, and erectile dysfunction.
Carbonic anhydrase inhibitors. Generally used if you can’t tolerate beta blockers. They can also have systemic side effects, including frequent urination and tingling in the fingers and toes.
Rho kinase inhibitor. This medication suppresses the enzymes that produce fluids. Side effects can include redness and discomfort in the eye.
To improve drainage:
Prostaglandins. This is generally the medication your eye doctor will try first, as it’s well tolerated by most, although it can cause your eye color to change (yes, it really can) by darkening the iris or the pigment of the eyelashes. It can cause some eye discomfort. There are multiple preparations, and your eye doctor may try more than one to get the best results.
Miotic or cholinergic agents. These are rarely prescribed, as you have to use them up to four times a day and they have a tendency to cause nearsightedness as well as headaches. In general, these are only prescribed if other medications are not working.
To do both:
Alpha-adrenergic agonists. This drug has both effects but is another one that can cause systemic effects, including irregular heart rate, high blood pressure, and fatigue.
For most patients, prostaglandins, beta blockers, or both will be prescribed. If you receive eye drops, you should close your eyes for one to two minutes after putting the drops in and press lightly at the inner corner of your eyes to close the tear duct. Also, apply multiple eye drops at least five minutes apart.
If eye drops alone are not working, the doctor might also give you an oral carbonic anhydrase inhibitor. Be aware that this medication can cause depression.
Surgery
Not every patient will end up needing surgery. For those that do, there are a number of procedures that might be recommended. Some of these surgical treatments can be done in the ophthalmologist’s office, especially if you are already seeing a glaucoma specialist. For others, you might have to go to the hospital.
Here are some of the surgical options:
Trabeculoplasty:
This is a laser surgery performed in the office or at an outpatient center. This is a treatment for open-angle glaucoma (the most common form) in which the doctor uses a small laser to open up your clogged channels and improve the flow of fluid from the eye. It can take a few weeks to have a noticeable effect. Generally, this kind of surgery has to be repeated every one to five years. You may or may not still need medication after the surgery. You will probably have to use different eye drops or take an oral NSAID to keep post-operative inflammation down. Downtime is no more than a day.
Iridotomy:
This is the version for angle-closure glaucoma. The surgeon will use a laser to make a tiny hole in your iris. In many cases, this is the first line of attack for angle-closure, which is more serious (but fortunately rarer). Most patients will still need to take glaucoma medication after the procedure. It has slightly more downtime than the first option and requires anti-inflammatory eyedrops for a few days. Blurred vision is normal for a short period of time after the operation. Generally, this surgery is permanent and does not have to be redone unless you develop cataracts.
Trabeculectomy:
This is a more complicated surgery done in an operating room. The surgeon will make a small hole in the sclera – that is the wall of the eye – with a trapdoor over it, to allow some aqueous humor to drain into a bubble, called a filtration bleb. This is hidden under your upper eyelid. The fluid will be reabsorbed by your body. Trabeculectomy is recommended for advanced patients who may no longer be responding to other treatments. It can cause an extended period of blurred vision, usually for one to two weeks, and often vision does not return to normal for two to three months. You will have to go back to the clinic two to three weeks after surgery to have the sutures removed. Patients will also have to wear a shield to protect the eye at night, and use post-operative eye drops for two to three months. Most patients need a couple of weeks off of work or even more if involved in manual labor. There is a variety of other follow-up. However, many patients will never need this level of surgery.
Glaucoma Drainage Devices
Other patients with severe glaucoma may need a drainage tube implanted in their eye, which will divert fluid to a reservoir under the eyelid, from which it can be reabsorbed by the body. This is sometimes called an aqueous shunt. These devices are generally only needed by a small subset of patients. If your glaucoma was caused by an eye injury, you are more likely to need this surgery. It’s also common for neovascular glaucoma, which is caused by diabetes. Implants are generally considered a last resort for patients who are not responding to other treatment and can cause complications, including corneal injury and scarring.
Other Treatments and Therapies
In addition to medication and/or surgery, your eye doctor may recommend some minor lifestyle changes to help reduce your risk of vision loss. Remember that damage done to your vision by glaucoma is permanent. There are some herbal remedies advertised to help with glaucoma, but none of these are tested. Medical marijuana is also not a recommended glaucoma treatment, mostly because it is not particularly effective. Recommended lifestyle changes might include:
Ensuring that your diet contains enough zinc, copper, selenium, and vitamins C, E, and A. All of these help eye health in general.
Exercise, but make sure you talk to your doctor. Aerobic exercise can help by improving blood flow to your optic nerve, although it only helps with open-angle glaucoma. The benefits only last as long as you keep up the routine.
Reduce caffeine intake. Too much caffeine can increase your eye pressure, so avoid very strong coffee and certain highly caffeinated sodas.
Slow your fluid intake. Avoid drinking a lot of fluid quickly, as this can temporarily increase eye pressure and may cause damage.
Use a wedge pillow to elevate your head by about 20 degrees.
If at risk of angle closure glaucoma, make sure to practice good stress management. Meditation may help, but avoid yoga positions that involve holding your head upside down, as those can increase pressure.
If you are at high risk of glaucoma, you should talk to your eye doctor about screening options, which might include tonometry and gonioscopy. If you or a loved one has a glaucoma diagnosis, then make an appointment today to discuss your options.
