Q: What is Glaucoma?
A: Glaucoma is a group of diseases that damage the eye’s optic nerve and can result in vision loss and blindness. However, with early detection and treatment, you can often protect your eyes against serious vision loss.
Q: How does the optic nerve get damaged by open-angle glaucoma?
A: Several large studies have shown that eye pressure is a major risk factor for optic nerve damage. In the front of the eye is a space called the anterior chamber. A clear fluid flows continuously in and out of the chamber and nourishes nearby tissues. The fluid leaves the chamber at the open angle where the cornea and iris meet. (See diagram below.) When the fluid reaches the angle, it flows through a spongy meshwork, like a drain, and leaves the eye.
Q: Can I develop glaucoma if I have increased eye pressure?
A: Not necessarily. Not every person with increased eye pressure will develop glaucoma. Some people can tolerate higher levels of eye pressure better than others. Also, a certain level of eye pressure may be high for one person but normal for another.
Q: Can I develop glaucoma without an increase in my eye pressure?
A: Yes. Glaucoma can develop without increased eye pressure. This form of glaucoma is called low-tension or normal-tension glaucoma. It is a type of open-angle glaucoma.
Questions and Answers About Glaucoma by H. George Tanaka, MD
Q: How common is glaucoma?
A: Glaucoma affects more than 3 million Americans. The scary part is that half of those people don't even know they have glaucoma. And with the number of aging Americans expected to increase in the next century with the "baby-boomer" generation, glaucoma will continue to be a major public health concern in the future.
Q: What is glaucoma, anyway?
A: Glaucoma is not just one disease, but a group of many different diseases. They all have one thing in common – damage to the nerve that connects the eye to the brain, called the optic nerve, which results in a gradual loss of vision. Many, but not all, cases are associated with elevated pressure in the eye.
Q: Who is at risk for glaucoma?
A: The risk of developing glaucoma increases with a person's age. Young adults and even children can develop glaucoma, but this is very uncommon. People who have a blood relative with glaucoma are more likely to develop glaucoma themselves. People who have taken steroid medications for a long time (such as Prednisone or steroid eye drops), have seriously injured their eyes, or have diabetes are at higher risk for glaucoma. Particular kinds of glaucoma are more common in certain ethnic groups. African-Americans are at higher risk of developing primary open-angle glaucoma. People of Scandinavian or Russian ancestry are more likely to develop pseudo exfoliative glaucoma. Even the type of eyeglasses prescription you have predisposes you to certain types of glaucoma. Near-sighted persons are more likely to acquire pigmentary glaucoma. Far-sighted persons are more likely to develop angle-closure glaucoma.
Q: Doesn't glaucoma have any symptoms? My vision seems to be fine. My eyes feel normal. Does that mean I don't have glaucoma?
A: No! The vision we use every day to read, drive, or watch TV is our central vision. Glaucoma doesn't affect the central vision until it is very advanced. Glaucoma usually destroys the peripheral vision before it affects central vision. Because we're not aware of our peripheral vision, a person who has lost most of his or her peripheral vision from glaucoma may not even know there's a serious problem with his or her eyes.
Except in rare cases, a person who has glaucoma with high eye pressure usually feels fine. That's because the pressure has risen very slowly in the eye. Chances are, the way your eyes feel has nothing to do with how high the pressure is in your eye. When people complain that their eyes are irritated, or feel a "pressure" in their eye, or their eyes "just don't feel right", it is usually caused by something else besides the eye pressure.
Q: So how can I or anyone else tell if they have glaucoma?
A: You can't! Remember, glaucoma has no symptoms in its early stages. That's why it's so important to have a complete eye examination that includes measuring your eye pressure. But remember, you can have glaucoma even if your eye pressure is "normal." That's why I would also carefully examine your optic nerve to look for characteristic signs of damage from glaucoma. If your nerve looks damaged, then I would order a special test of your peripheral vision. This is called a visual field test. It is painless and takes about 5 to 15 minutes per eye. I would examine the drainage area of your eye to determine whether or not it's blocked. That's called gonioscopy. Finally, if I'm not sure it's glaucoma or if the glaucoma is in an early stage, I would get photographs of your optic nerves for future comparison. Newer tests for glaucoma such as computerized optic nerve scanning are also available. In the future we may have practical genetic testing for glaucoma.
Remember, glaucoma is one of the few eye diseases without any symptoms until it is very advanced. No redness. No pain. No tearing. No blurry vision.
Q: Now I'm a little confused about this eye pressure thing. Isn't glaucoma the same thing as having too much pressure in the eye?
A: In most -- but not all -- cases, glaucoma is associated with an abnormally high pressure in the eye. An elevated pressure is considered greater than 21, measured in units called millimeters of mercury. This cutoff value of 21 for "normal" eye pressure is based on population studies of normal people. However, 21 is not a magic number which separates normal from abnormal eyes. Not too long ago, all people with elevated eye pressure were considered to have glaucoma. However, we know now that even though high eye pressure is a strong risk factor for glaucoma, not all people with elevated eye pressure develop glaucoma. Even more importantly, many people who develop glaucoma have eye pressures within the "normal" range of under 21. Using eye pressure alone to decide who does and doesn't have glaucoma is misleading -- it over-diagnoses many people with glaucoma who don't really have the disease and it misses many people who actually have glaucoma. In summary, eye pressure is not the disease.
Q: OK, so high eye pressure isn't the same thing as glaucoma. Let's say I did have glaucoma. How would you explain what's wrong with my eye?
A: I would begin by pointing out that your eye is a lot like a kitchen sink with its own biological plumbing system. One part of the eye acts as an internal "faucet" and produces fluid which circulates within the eye, just like a faucet filling up a sink. This fluid provides nutrition to the inside of the eye. Another part of the eye acts as an internal "drain" where the fluid in the eye escapes into the circulation. The basic problem in all types of glaucoma is this: the fluid produced by the faucet has difficulty getting out through the drain. This causes the pressure in the eye to build up which damages the optic nerve over time and eventually causes blindness.
Q: Now that makes sense for glaucoma associated with high pressure. What about those cases where the pressure is "normal"?
A: You've just asked the most important question about glaucoma today. Glaucoma experts have been researching and arguing about this issue for years. We know that an eye pressure of 15 in one person may be just fine, but the same pressure of 15 in another person may lead to blindness. So it's likely that the optic nerve's sensitivity to eye pressure varies from person to person. The truth of the matter is, there are probably several factors that contribute to damaging the optic nerve in glaucoma, and eye pressure is only one of them. You see, the real "big picture" of glaucoma is much more complicated than the kitchen sink analogy I've just described. Glaucoma is more than a "plumbing" problem in the eye.
Q: Then why do you doctors pay so much attention to eye pressure in glaucoma?
A: Well, for one thing, eye pressure is probably the most important factor in most cases of glaucoma. Secondly, eye pressure is the only thing we can treat in glaucoma right now. All currently available treatments for glaucoma – medicines, laser, and surgery – lower eye pressure. We can't fix the optic nerve once it's damaged, and we can't transplant optic nerves like we do with other body organs. Future scientific research may lead to better ways of treating glaucoma besides lowering eye pressure.
Q: Tell me about some of this research.
A: As I mentioned earlier, there are probably several other things damaging the optic nerve in glaucoma that aren't related to the pressure in the eye. Poor blood flow to the optic nerve, special molecules called free radicals, an abnormal immune system, and complicated "self-destruct" processes in optic nerve cells may play a role in glaucoma. A very exciting and active area of medical research called neuroprotection is focused on learning more about the biochemical and genetic mechanisms leading to the death of nerve cells in glaucoma and other diseases. I think that as we enter the 21st century, we're getting closer to some real breakthroughs in early diagnosis and better treatment of glaucoma.
Q: That sounds encouraging. Now earlier you mentioned there being several different kinds of glaucoma. Isn't all glaucoma the same?
A: No. The end result of all untreated glaucoma is the same: blindness from optic nerve damage. But there are many ways of producing that end result. The different kinds of glaucoma fall into two basic categories: open-angle and closed-angle. The "angle" is just an eye doctor's name for the drainage area where fluid leaves the eye. Open-angle glaucoma is the most common type of glaucoma in the United States. In open-angle glaucoma the drain in the eye looks open, but doesn't work properly. It's like a kitchen drain that looks open at the sink, but is clogged with debris that you can't see. In closed-angle glaucoma the opening of the drain is physically blocked off, preventing fluid from entering the drain itself, just like a paper towel covering the opening to a drain.
Q: What causes glaucoma?
A: The many different kinds of glaucoma have different causes. The exact cause of open-angle glaucoma, the most common type in the United States, is not known, but doctors and scientists are getting closer to the answer. We don't know exactly why the drain doesn't work in open-angle glaucoma. It has to do with abnormal genes, but we don't know exactly which genes are responsible or how they cause glaucoma. Open angle glaucoma can also be caused by severe injury to the eye or taking steroid medications.
Closed-angle glaucoma may result from having angles which are narrow. Narrow angles may close off suddenly or gradually with time and are more common in people who are farsighted. Closed angle glaucoma may also be due to blood vessels growing into the drain or previous inflammation in the eye.
Q: High blood pressure is common and glaucoma, which is associated with high eye pressure, is also common. Is glaucoma caused by high blood pressure?
A: A lot of people ask me that and the answer is no. As you said, glaucoma and high blood pressure are both common diseases, so many people will have both. Fluid made by the eye's "faucet" does come from the blood. This fluid eventually returns to the blood after leaving the eye through the "drain". However, your blood pressure has a limited effect on your eye pressure. This is because the plumbing system of the heart and blood vessels is separated from the plumbing system of the eye. It's like the plumbing system in your house being connected to, but separate from, the water system in your neighborhood. You can control how fast water flows out of the faucet in your kitchen even though the pressure in the water pipes going to your house may be much higher. Remember, the basic problem in glaucoma has nothing to do with too much fluid being produced in the eye. The problem is not enough drainage of fluid out of the eye.
Q: Another common problem in modern life is stress. Is glaucoma caused by stress?
A: Again, the answer is no. Stress does have many harmful effects on the body – high blood pressure, heart disease, and immune system dysfunction, to name a few. However, stress does not cause glaucoma. The pressure in your eye does not reflect your emotional state. Many people suffer from stress and develop tension headaches. These headaches can cause pain around the eye which is not caused by a problem with the eye itself. Reducing stress has many health benefits, but it may not have any impact on your eye pressure. Severe emotional stress causes pupil dilation which may narrow the drain further in people with narrow angles or chronic angle-closure glaucoma.
Q: How about reading habits, like excessive reading, reading too much fine print, etc. Do they have anything to do with causing glaucoma?
A: Some research suggests that prolonged focusing on close objects may contribute to a condition called pigment dispersion, which in some cases leads to glaucoma. Other than that possible association, as far as we know, people who do a lot of reading or read a lot of fine print are not at increased risk of developing glaucoma.
Q: How about spending a lot of time in front of a computer?
A: One research study showed a weak link between the amount of time working on a computer and the risk of developing glaucoma; however, this study had several design flaws. It would be safe to say that prolonged computer work does not cause glaucoma.
Q: How about watching a lot of TV?
A: Watching TV has nothing to do with glaucoma.
Q: OK, I understand that glaucoma and high eye pressure are not the same thing. So tell me why is it so important to follow my eye pressure?
A: High eye pressure is a risk factor for developing glaucoma. The higher the pressure, the higher the risk of developing glaucoma. Someone with high eye pressure, but not glaucoma, should be followed by an eye doctor with regular exams and tests in order to detect glaucoma in its early stages when it is most treatable. It's important to remember, though, that having high eye pressure alone is not the same thing as having glaucoma. You only have glaucoma when your doctor detects a certain pattern of damage to your optic nerves.
Q: What is ocular hypertension?
A: Ocular hypertension is a term that means the pressure is high in the eye, but this high pressure has NOT damaged the optic nerve. (If your optic nerve is damaged by high pressure, then you have glaucoma.) Ocular hypertension is a risk factor for developing glaucoma, but not all people with ocular hypertension develop glaucoma. Ocular hypertension is not caused by or related to having high blood pressure. Remember, the plumbing system in your eye is separate from the plumbing system of your heart and blood vessels. Both conditions are common, so many people will have both systemic and ocular hypertension.
Q: Let's say I have ocular hypertension, which, as you said, means my eye pressure is high. Should I be taking eye drops to lower my eye pressure?
A: That's a good question. Again, the answer depends on whether or not you have damage to your eye from the high eye pressure. If there is damage to your eye which is picked up by examining your optic nerve or doing a visual field test, then you have glaucoma. Glaucoma is treated initially with pressure-lowering eye drops. You may also be given pressure-lowering medication if your doctor feels you are at very high risk of developing glaucoma. For example, if you have family members who have gone blind from glaucoma or your eye pressure is extremely high.
If your eye pressure is elevated and there is no evidence of damage to your eye, then the decision to start taking pressure-lowering eye drops is more difficult. Eye drops need to be taken every day for the rest of your life. Not everyone with high eye pressure develops glaucoma. If everyone with high eye pressure were given eye drops, many people would be treated unnecessarily. On the other hand, lowering the eye pressure does lower the risk of developing glaucoma in the future.
Q: So there are pros and cons of treating ocular hypertension.
A: Exactly. Fortunately, if glaucoma does develop, it develops slowly, usually over many years. Suppose in your case I decide not to start treatment and simply monitor your eyes with periodic exams and tests. If glaucoma does develop under such close monitoring, then the amount of damage that would occur would be so small that it would have very little effect on your vision or your life in general. With this evidence of damage to your eye, we would then have a strong reason to start treatment.
A nationwide medical study called the Ocular Hypertension Treatment Study has been done to answer the question of whether or not to treat people with ocular hypertension. The results of this study show that the risk of developing glaucoma depends on a person's age, how high their eye pressure is, what their optic nerve looks like, and the thickness of the front part of the eye called the cornea. The following factors are associated with a greater risk of developing glaucoma: older age, higher eye pressure, greater optic nerve cupping (this relates to the physical appearance of your optic nerve), and thinner cornea.
Q: It sounds like a decision that needs to be made on a case by case basis.
A: Right. Most people would prefer not to take drops every day for the rest of their life if they didn't absolutely have to. On the other hand, some people would rather take the drops and sleep better at night knowing their eye pressure was being lowered.
Q: Can I tell what the pressure is in my eyes by how my eyes feel?
A: Not really. High pressure causes eye pain only if it rises to a very high level very quickly. This can happen in a relatively uncommon type of glaucoma called acute-angle closure glaucoma which is an eye emergency. However, the only reliable way to know your eye pressure is to have it measured by your eye doctor. There are many causes of pain and discomfort in or around the eyes that have nothing to do with the eye pressure. High eye pressure alone is rarely a cause of eye discomfort.
Q: Is the pressure in both my eyes always the same?
A: No, not always. Usually the pressures in the right and left eyes are similar, but they can also be quite different from each other.
Q: My eye pressure is always a different number every time I have it measured in my doctor's office. How accurate are pressure readings? Is it normal for my eye pressure to change so much?
A: Great questions. First of all, you have to understand that there is a measurement error of about 2 when we take a pressure reading from the eye. So an eye with a pressure of 18 could be measured as low as 16 or as high as 20. Also, we as physicians forget that patients can be very tense when they have their eye pressure taken. Holding your breath, tightening your stomach, and squeezing your eyelids can all raise the pressure in the eye during the few seconds your doctor takes a pressure reading. Even a tight necktie or collar can raise the eye pressure! Although it's a painless procedure, I've even had some nervous patients faint during a pressure measurement!
Now I'll answer your second question. Yes, the pressure in your eye can vary from hour to hour, day to day, and even season to season. Many people have higher eye pressures in the morning and lower pressures in the afternoon or vice versa. Therefore, the time at which your doctor checks your eye pressure is important. A certain amount of variation in the eye pressure is normal. However, certain types of glaucoma can cause a large variation in the eye pressure from visit to visit.
Q: What is a "safe" or "good" pressure for my eye if I have glaucoma?
A: I get asked this question all the time by my patients. The answer is -- it depends. It depends on many factors: how much damage the glaucoma has caused, the level of pressure which caused this damage, the time period over which this damage occurred, and the age and overall health of the patient.
Generally, if you've had a lot of damage from glaucoma, then your eye pressure should be lower than if you've had just a little damage from glaucoma. That's because the risk of blindness during your lifetime is greater if your optic nerve has suffered a lot of damage. The amount of glaucoma damage can usually be determined by examining the optic nerve and performing a visual field test.
Generally, the younger a patient is with glaucoma, the lower their eye pressure should be. This is because glaucoma is a chronic and incurable disease. Lowering the eye pressure can significantly slow down (but not completely stop) how fast the glaucoma gets worse. I expect a younger patient with glaucoma to live a long time which means a greater chance of losing vision during his or her lifetime.
Based on the above considerations, I will try to lower your pressure to a certain level at which further damage to your optic nerve is unlikely to occur. This level of eye pressure is called a "target pressure." The target pressure is the goal you and your doctor are trying to achieve with treatment. The target pressure is the best estimate of a "safe" pressure, but it may need to be changed if the damage continues to get worse in spite of reaching the target pressure with treatment.
Q: So the goal of treatment is to reach the target pressure, right?
A: Yes and no. As a physician and a glaucoma specialist, my job is not to lower eye pressures, protect optic nerves, or preserve visual fields. My job is to treat patients. The immediate goal of treatment is to lower the eye pressure to the target pressure. That goal is a number and it's easy for any doctor to measure with an instrument. The ultimate goal of treatment, however, is to prevent blindness and preserve a patient's quality of life. That is much harder to measure, and it takes communication and a trusting relationship between a doctor and a patient.
In picking a target pressure I have to balance two risks: On the one hand, I have to weigh the risk of further optic nerve damage affecting a patient's quality of life. The lower the eye pressure, the lower the risk of further damage. On the other hand, my treatment to prevent further damage carries a risk of harming the patient's quality of life as well. The lower the eye pressure, the greater the risk of reducing quality of life from multiple medications or having a complication from surgery. We have to remember that the treatment of glaucoma shouldn't be worse than the glaucoma itself.
I weigh these two risks in deciding what eye pressure is "low enough," "safe," or "good". It's different for each patient and it may change depending on how the glaucoma behaves over a patient's lifetime. Things would be much easier if we always knew how fast the glaucoma was progressing and how long a patient was going to live. As I tell my patients, "It's OK to go blind after you die, but not before." Because glaucoma is a disease that takes years and even decades to unfold, we usually have time to wait and see if our treatment is working. As long as things aren't getting worse, and the patient is tolerating the treatment, we're OK.
Q: Can I measure the pressure in my eyes at home?
A: There are instruments which are available which allow patients to monitor their eye pressure at home. They are very expensive and somewhat cumbersome to use. Not many patients use these devices. It is important to remember that the exact number of your pressure from day to day or week to week is not as important as the effect the eye pressure has on your optic nerve. Having your optic nerve examined and your visual field tested is just as important as having your pressure measured.
Q: Will there ever be a cure for glaucoma?
A: Right now there is no cure for glaucoma -- damage to your optic nerve and vision lost from glaucoma can not be restored. Glaucoma can only be treated.
Research is being done in many laboratories and clinics around the world to find a cure for glaucoma as well as better treatments. But until a cure is found, the best way of preventing blindness from glaucoma is through early detection and treatment.
Q: We talked a little bit about treatment earlier. How is glaucoma treated and what are the goals of treatment?
A: The only treatment available today for glaucoma is to lower the eye pressure. There are basically three ways to do this: eye drops, laser treatment, and surgery.
Treating your glaucoma protects the vision remaining in your eyes. The purpose of treating glaucoma is to prevent further loss of vision and eventual blindness. Treating glaucoma does not make your vision better.
Q: So the first line of treatment is using eye drops. How do eye drops work?
A: There are many different kinds of eye drops used to treat glaucoma. Remember how we talked about your eye acting like a kitchen sink? Well, eye drops work in one of two ways – they turn down the "faucet" in the eye so that it produces less fluid, or they cause the "drain" to work better, making it easier for fluid to escape from the eye.
Q: How can someone tell if his or her eye drops are working?
A: By measuring the eye pressure. But that's not enough. Examining your optic nerve and performing visual field tests tells your doctor if lowering the eye pressure is preventing further damage to your eye. This is ultimately the most important indication that your treatment is effective.
Q: Can eye drops cause side effects and is there any danger to taking eye drops?
A: It's an unfortunate reality that all eye drops have side effects. Most side effects are merely a nuisance. Each eye drop has its own particular side effects, and not all patients get every possible side effect. (See list below) Serious side effects from taking glaucoma eye drops are rare, but can result from underlying medical conditions. Your doctor needs to know all your medical problems and what other medications you're taking before prescribing eye drops for your glaucoma.
POSSIBLE SIDE EFFECTS OF EYEDROPS
Timoptic, Betagan, Optipranolol, Betoptic, Ocupress, Betimol, Combigan, Cosopt: shortness of breath, slowed heart rate, decreased blood pressure, dizziness, fatigue, weakness, decreased exercise tolerance, depression, confusion, impotence, memory loss, anxiety, hallucinations, insomnia Trusopt, Azopt, Cosopt: metallic taste in mouth, red and itchy eyes, SULFA ALLERGY Propine: red and itchy eyes, tearing, palpitations, elevated blood pressure, tremor, headache, anxiety Pilocarpine: headache, dim vision, red and itchy eyes Carbachol: headache, dim vision, red and itchy eyes, stuffy nose, sweating, increased salivation Diamox, Neptazane: nausea, lack of appetite, fatigue, tingling in fingers and toes, kidney stones, lethargy, weight loss, depression, dehydration, rash, potassium loss, aplastic anemia, SULFA ALLERGY Alphagan, Combigan, brimonidine: dry mouth, drowsiness, red and itchy eyes, MAO inhibitors Xalatan, Travatan, Lumigan: turns blue, hazel, or green eyes brown permanently, longer eyelashes, fine hair growth around eyelids, darkening of skin around the eyes, red and itchy eyes, flu-like symptoms, muscle aches, blurry vision, stinging
(The above side effects are only a partial listing.)
Q: What happens if I start taking a drop and get one of these side effects?
A: You should tell your doctor if you experience any side effects while taking your glaucoma medication. Many patients are unaware that certain chronic symptoms are due to their glaucoma eye drops. Under your doctor’s guidance, you may stop the medication and see if the side effect goes away. Unfortunately, many patients end up not being able to take certain eye drops because the side effects are too bothersome.
Q: How can one little eye drop cause side effects in the rest of my body? I never would have thought that could happen.
A: You’d be surprised. Side effects in your body are caused by the medicine getting into the bloodstream after you put them in your eyes. Here’s how that happens: Your eyelids contain tiny ducts which carry the tears your eyes make down into your nose. If you didn’t have these ducts, you would be constantly crying since your tears would have no place to go except down your cheeks. When you put eye drops in your eyes, they travel from your eyes down these ducts into your nasal passages. There the medicine in the eye drops gets absorbed directly into your bloodstream. That’s why eye drops can cause side effects such as shortness of breath, drowsiness, depression, or fatigue.
Q: Can I do anything to prevent or minimize these side effects?
A: Yes -- by taking your eye drops properly. Here’s how:
1) Stand in front of a mirror.
2) Use your finger to pull your lower eyelid down.
3) Place only one drop of medication on the pink area inside your eyelid. 4) Do the same for the other eye if you’re using the drop in both eyes.
5) Close your eyes.
6) With your thumb and index finger gently press the tiny bumps in the inside corners of your eyes near your nose. (See picture)
7) Take a deep breath and relax for one minute.
By closing your eyes and pressing the inside corners of your eyes, you block the ducts that carry the eye drops into your nasal passages. This prevents your eye drops from getting into the bloodstream and causing side effects in the rest of your body. This maneuver is called punctal occlusion and should be performed after every eye drop.
Q: And I only have to put in one drop of each medicine, right?
A:Yes – one drop is more than enough. If you feel the drop go in your eye, it went in. Don’t put in extra drops “for good measure!” Although this probably won’t harm your eye, you’re wasting the medicine if you do. Some patients store their drops in the refrigerator to make them cold. That way, when they put the drops in their eyes, they can really feel if the drop went in.
Q: I’m really bad at putting anything in my eye. Any suggestions?
A:Remember that the drop doesn’t have to be put on the white or colored part of the eye. Placing the drop on the inside of the lower eyelid is good enough. When you close your eyes after putting the drop on the inside of the lower eyelid, the medicine gets to where it’s supposed to go. Trust me. It also helps to use a mirror. If even that doesn’t work, get someone else to put your drops in for you. But make sure they know how to put your drops in properly. And remember to close your eyes and press the inside corners of your eyes after every drop!
Q: Got it – inside of the lower eyelid, close eyes, press inside corners. OK, is it necessary to put one drop in each eye at a time?
A: If you are taking more than one kind of eye drop for your glaucoma, you should wait at least five minutes in between drops. This prevents one drop from washing out the other drop before it has a chance to work properly.
Q: OK, let’s suppose I’m taking more than one eye drop for my glaucoma. Is it important to take my eye drops in a certain order?
A: No. The order in which you take your eye drops is not important. But you should wait at least five minutes in between drops.
Q: What happens if I miss a drop? Should I put in an extra drop for my next dose?
A: No. Putting in an extra drop the next time you’re supposed to take your drops does not help! Drops need to be taken at different times of the day to keep the eye pressure under control around the clock. The best thing to do is not forget your drops in the first place! The next best thing is to put the drop in as close as possible to the correct time. Even putting the drop in a few hours late is better than completely missing a dose. You need to make putting in your eye drops part of your daily routine. Every time you forget to take a drop, the pressure in the eye will go up, even though you won’t feel it, and this will slowly damage your eye over time. Remember, no one else can take your drops for you, and you’ll be the only person who suffers as a result of forgetting to take your drops.
Q: Should I take my eye drops the day I’m supposed to see my eye doctor?
A: Yes -- yes -- yes! Follow-up visits are important for checking eye pressures. If you don’t take your eye drops the same day you see your doctor, he or she has no way of knowing if the eye drops are working or not! It is very important to take your eye drops every day. You should not skip taking your eye drops unless your doctor specifically tells you to do so.
Q: For women, is it harmful to put in my eye drops without taking off eye makeup?
A: No, although the eye drops may cause your eyeliner to run and some mascara can get into the eye which could cause some irritation.
Q: Can glaucoma eye drops interact with other medications?
A: Serious interactions between eye drops taken for glaucoma and medications taken for other medical conditions are uncommon. You should tell your doctor what medications you take for your other medical problems and if any of your other medications have changed since your last visit.
Q: Can glaucoma eye drops affect any other medical conditions?
A: Yes. Beta-blocker eye drops (such as Timoptic, Betagan, Betimol, Betoptic, Cosopt, Ocupress, Optipranolol) should be avoided if possible in patients with asthma, emphysema, severe heart failure, slow heart beat, or low blood pressure. Diamox or Neptazane pills should be avoided in patients with kidney disease or patients taking digitalis. Again, it’s very important to tell your doctor about your other medical conditions if you’re going to be treated for glaucoma.
Q: Some over-the-counter medications contain warnings saying I shouldn’t take them if I have glaucoma. What should I do?
A: I get asked that question a lot. Remember that not all glaucoma is the same. Some medications such as decongestants, antihistamines, and sleeping pills can cause pupil dilation as a side effect. This can potentially cause your angle to narrow further if you have narrow angles or angle-closure glaucoma. These medications are OK to take if you have open-angle glaucoma which is the most common type of glaucoma.
Q: How long does a person with glaucoma need to take eye drops?
A: Usually for the rest of his or her life. Unfortunately, glaucoma is a lifetime disease that never goes away or gets better. Glaucoma can be controlled by keeping the eye pressure down at a safe level. You do this by taking eye drops or pills for the rest of your life. You need to make it part of your daily routine.
Q: Is there anything else besides taking eye drops that will lower eye pressure?
A: Research has shown that regular aerobic exercise can lower eye pressure slightly. Aerobic exercise has other health benefits, so I recommend talking to your primary care physician about starting a regular exercise program. Even with exercise, however, you may still need to take eye drops to control your eye pressure adequately.
Q: Can I use marijuana to treat my glaucoma?
A: Medical research has shown that using marijuana does lower eye pressure. However, the effect of marijuana on eye pressure is very brief. A person would need to use marijuana nearly constantly to control his or her eye pressure as well as taking just one or two drops a day. Smoking marijuana also has other health risks. In general, marijuana is not a very good drug to treat glaucoma.
Q: Why do some people need to take more than one eye drop for their glaucoma?
A: Some glaucoma is more “stubborn” than others. Patients with severe glaucoma or very high eye pressure may need more than one eye drop to keep the eye pressure at a safe level. If one eye drop doesn’t do the job, your doctor will switch to another drop or add another drop and recheck the eye pressure. If the eye pressure is still too high, he or she will add more medications until the eye pressure is under control. Finding the right eye drops for your glaucoma is like buying shoes – it’s a trial-and-error process of getting the right “fit”. It requires repeat visits with your doctor to 1) check the eye pressure to see if the eye drops are working and 2) detect any side effects which may be caused by the eye drops.
Q: I’ve heard patients complain, “I’m taking so many different eye drops for my glaucoma and my pressure still isn’t low enough!” What’s going on?
A: Most people who have glaucoma are able to lower their eye pressure to a safe level by taking one or two eye drops. Some drops work very well in some people but may not work at all in other people. Some drops work well initially, but then don’t work as well after being used for a while. Finally, the glaucoma may just become very “stubborn” and not respond well to eye drops.
Q: When and why does a patient with glaucoma need to have surgery?
A: Surgery may be a better option for treating glaucoma than taking medications for several reasons. In some cases of glaucoma, the eye pressure cannot be lowered to a safe level with medications alone. Sometimes, no matter what medications are used, the eye pressure is still too high and the risk of further damage to the eye is great. Second, side effects from medications may prevent their long-term use. Third, patients with glaucoma often have many other medical problems such as high blood pressure, diabetes, heart disease, and high cholesterol. Taking several different kinds of eye drops in addition to many other kinds of medication can be too difficult for some patients. Because it is so difficult to take many different kinds of pills and eye drops several times a day, day after day, and week after week, many patients forget to take their medications properly or skip their medications. This is dangerous because not treating glaucoma properly causes further damage to the eye. Finally, patients on a fixed income may not be able to afford their medications which may be very expensive. For any or all of these reasons, surgery may be needed to control glaucoma.
Q: What kinds of surgery are there?
A: There are basically two kinds: laser surgery and incisional surgery.
Q: What kinds of laser surgery are there for glaucoma?
A: Currently, there are several different types of laser surgery for glaucoma. The two most commonly performed are trabeculoplasty and iridotomy.
Q: OK, let’s start with trabeculoplasty. Explain what it is and why it’s done.
A: Currently, there are two kinds of laser trabeculoplasty: Selective laser trabeculoplasty (SLT for short) and argon laser trabeculoplasty (ALT for short). Both are used to treat open-angle glaucoma. When I perform a trabeculoplasty I focus a microscopic beam of laser light around the “drain” in the eye called the trabecular meshwork. This area is where the fluid inside the eye leaves the eye. Fifty to one hundred tiny spots of laser energy are used. Each spot is 50 to 100 microns in diameter – a micron is one-thousandth of a millimeter, so the spots are very small. Each spot is turned off after one-tenth of a second. Laser treatment is used to make it easier for the fluid to escape from the eye.
Q: Are you burning a hole in the eye?
A: No. A lot of my patients think that’s what I’m going to do, but a trabeculoplasty is actually very much gentler than that. The laser does NOT burn a hole from the inside to the outside of the eye. Doctors aren’t even sure exactly how this procedure works, but it’s thought that when the drain heals from the laser treatment, changes occur in the tissue which makes it easier for fluid to escape from the eye.
Q: When do you decide to do laser? Who is a good candidate for trabeculoplasty?
A: Trabeculoplasty is usually done if eye drops don’t work to control the eye pressure, or if you can’t take eye drops because of side effects, inconvenience, or cost. Trabeculoplasty works best in chronic open-angle, pigmentary, and pseudoexfoliative glaucoma. Older patients have better success than younger patients. Other types of glaucoma respond poorly or not at all to trabeculoplasty. Your doctor will advise you on the decision to have trabeculoplasty.
Q: Now earlier you mentioned two types of laser surgery. Let’s go over iridotomy, the second type of laser surgery.
A: Laser peripheral iridotomy (LPI for short) is used to treat narrow or closed-angle glaucoma. When I perform this type of laser surgery I use a microscopic beam of laser light to create a very small opening in the colored part of the eye called the iris. By creating this opening in the iris, the angle formed by the iris and cornea will become wider. This makes it easier for the fluid to escape through the drain of the eye.
Q: Why would I need to have an iridotomy?
A: People with narrow angles are at risk of developing acute angle-closure glaucoma. This type of acute glaucoma is an eye emergency in which the eye pressure rises very rapidly to high levels causing pain and possible permanent loss of vision in the eye. Iridotomy is performed in eyes with narrow angles to prevent an angle-closure attack from occurring. In people with partially closed angles, iridotomy is used to prevent further closure of the angle. Iridotomy will not work in certain types of angle-closure or in angles that have been closed for a long time.
Q: How are these laser procedures performed? What should I expect?
A: Both trabeculoplasty and iridotomy are performed as an outpatient office procedure on only one eye at a time. You sit at a special laser machine which looks very similar to the machine your doctor uses to examine your eye in the office. A drop of anesthetic is put in the eye. A special contact lens is placed on the eye with a special lubricant to hold the lens on the eye. You look straight ahead with both eyes open. Because a contact lens is used, you don’t have to worry about blinking during the treatment. During the treatment you will see many bright but brief flashes of light as the laser is turned on and off. You may also feel some of the lubricant on the contact lens dripping onto your cheek. It is important to realize this is normal and harmless and does not mean anything is leaking from inside your eye. The entire treatment takes less than five minutes.
Q: I really hate to have things done to my eyes! Is laser treatment painful?
A: Having the contact lens on your eye is not painful, since the surface of the eye is numbed with anesthetic. The laser energy is applied in brief pulses, each lasting only a fraction of a second. Some patients find the first few laser pulses startling, but not painful. Others find the treatment slightly uncomfortable. Most patients do not find the treatment painful at all.
Q: What should I expect after my laser procedure?
A: After the laser I need to check your eye pressure after the treatment. It is very common for the vision to be blurry and the eye to be irritated and red for a day or so after the procedure. This is caused by the lubricant used to hold the contact lens on the eye. This blurry vision, discomfort and redness usually go away after a day.
Q: Is there anything I should or shouldn’t do afterwards?
A: You should feel free to resume all your normal activities after the procedure: reading, eating, watching TV, working on the computer, exercising – all these activities have no harmful effect on the eye after laser surgery. Occasionally, I treat patients with an anti-inflammatory eye drop for several days. Aside from temporary redness in the eye, no one will be able to tell you had laser surgery since it doesn’t leave any visible scars on the eye surface.
Q: How long does it take for a trabeculoplasty to work?
A: Usually the effect of a trabeculoplasty isn’t known until several weeks after the treatment. So don’t be disappointed if the pressure doesn’t go down right away. The effect of an iridotomy is usually immediate. The angle opens up as soon as the hole in the iris is created. We usually see you a week or so after a laser procedure to make sure the eye pressure hasn’t gone up.
Q: Can laser procedures be repeated in the future?
A: At best the effect of a trabeculoplasty lasts a few years. If the eye pressure-lowering effect wears off, SLT can be repeated, possibly several times. In contrast to SLT, the chance of success for a second ALT is usually less than the initial ALT.
An LPI doesn’t need to be repeated unless the hole created in the iris scars shut. This happens infrequently and usually can be easily corrected with repeat treatment.
Q: What are the risks of laser treatment?
A: There is a small risk that the laser procedure may cause the eye pressure to actually go up. If this happens, it’s usually temporary. Additional medications may be given to bring the pressure down until the pressure returns to normal. Rarely, patients develop some inflammation in the eye following a laser procedure. It is very uncommon for permanent damage to occur to the eye as a result of trabeculoplasty or iridotomy.
Q: Will I still need to use my eye drops after a trabeculoplasty?
A: Probably. Trabeculoplasty is usually not effective enough to replace more than one eye drop. Trabeculoplasty is usually used after several medications have been tried. The more eye drops a patient is using before having trabeculoplasty, the more likely he or she will have to continue using those eye drops after trabeculoplasty.
Q: What other kinds of surgery for glaucoma are there besides laser surgery?
A: The most common surgery performed for glaucoma besides laser surgery is called a trabeculectomy.
Q: How does a trabeculectomy work?
A: The basic problem in glaucoma is that fluid produced inside the eye has difficulty getting out through the drain of the eye. A trabeculectomy builds a new drain from the tissues of your eye. Fluid escapes from inside the eye through this new drain and forms a small bubble under the skin covering the eye. This lowers the pressure in the eye.
Q: When do you decide to do trabeculectomy?
A: A trabeculectomy should be considered if eye drops and laser surgery don’t work well enough to control the eye pressure and prevent further damage to your optic nerve. Also, if you have advanced damage to your optic nerve from glaucoma and need very low eye pressures to slow down the damage and you are already taking multiple glaucoma drops; your doctor may recommend trabeculectomy. This is because in some cases in which the eye pressure remains high even while taking multiple drops, laser surgery is unlikely to lower the eye pressure sufficiently. In eyes with severe damage from glaucoma and very high pressure, trabeculectomy may be needed earlier to prevent complete blindness.
Q: Now, glaucoma can be cured with surgery, right?
A: No, not really. A cure for a disease is something that returns the body to its normal disease-free state. Right now there is no eye drop, pill, laser treatment or surgery that will bring back vision lost from glaucoma. Surgery can not cure glaucoma the same way cataract surgery “cures” a cataract by removing it, although I wish it could. If a person has glaucoma today, they’re going to have glaucoma for the rest of his or her life. Surgery and medications do not cure glaucoma – they control glaucoma by lowering the eye pressure.
Q: Let’s talk about how a trabeculectomy is performed. How long are you hospitalized? What can a patient expect?
A: Trabeculectomy is done as an outpatient procedure on only one eye at a time. The eye is put to sleep with an injection while you are under sedation. The surgery is usually painless after the eye is put to sleep. The area around your eye is cleaned and covered with sterile drapes. Like most eye surgery, trabeculectomy is done under a microscope. The surgery takes about 30 to 45 minutes to perform. Afterwards you will wear a patch over your eye for 24 hours. You return home the same day as your surgery. You do not stay overnight in the hospital.
Q: How successful is trabeculectomy?
A: Compared to eye drops or laser, trabeculectomy has a much higher chance of lowering the eye pressure and keeping the pressure low for a longer time. The success rate of trabeculectomy varies depending on the type of glaucoma and the type of patient, but overall is roughly 80%.
Q: How long does it take for trabeculectomy to work?
A: I always tell my patients that having the surgery is the easy part. The difficult part is the four weeks after the surgery when I and my patients need to work hard to make sure the eye heals properly. During this period of healing the eye pressure may be too low, too high, or “just right” depending on how the eye heals. For that reason, I see my patients at least once a week after surgery for 4 weeks to check the eye pressure and the healing of the eye. Sometimes I need to perform one or more office procedures during this time to “fine tune” the surgery and get the eye pressure “just right.” In most cases the pressure in the eye is reduced immediately after a trabeculectomy. However, the eye must heal completely before I can tell whether or not the surgery has been successful. This takes about four weeks and again, involves a lot of office visits after the surgery.
Q: Does a trabeculectomy make a person’s vision better?
A: No. In fact your vision may temporarily get worse immediately after the surgery. This is because lowering the pressure in the eye causes changes in the structure in the eye which take time to return to normal. After the eye heals from the surgery the vision should return to the same level as before the surgery. This usually takes a few weeks. Rarely, the vision stays blurry for several months. Glaucoma surgery does make cataracts grow faster; therefore, your vision may start to get worse several months after the surgery as your cataract gets worse. The cataract can be removed at a later time with cataract surgery. Patients may have difficulties with their vision after glaucoma surgery. Remember, though, that not doing the surgery and allowing the eye pressure to be too high will eventually lead to vision loss which is NOT reversible.
Q: Does a trabeculectomy ever need to be done twice?
A: As long as the drain created by the trabeculectomy continues to work, the pressure will stay well controlled. The body has a natural tendency to form scar tissue around the surgery. This scar tissue can block the drain, making it harder for fluid to escape from the eye. If this happens, you may need to have an office or laser procedure to “unclog” the drain built during the surgery. If this doesn’t work, you may need to go back to using some or all of your eye drops. Finally, if even the eye drops aren't able to control the pressure, you may need to have another surgery.
Q: What are the risks of a trabeculectomy?
A: Any kind of operation or procedure has some risk, just like driving a car or flying in an airplane has some risk. Serious complications as a result of trabeculectomy, such as bleeding and infection, are rare. You will most likely have some blurry vision for several days after the trabeculectomy. There is a chance that your vision could take weeks or even months to get better. You may need a second operation. There is a risk that the surgery may not work or stop working after several months or years. You may need to have a laser or office procedure done several days to weeks after the trabeculectomy to make sure the surgery is successful. On the other hand, the new drain in the eye may work too well or form an external leak and the eye pressure will be too low. This can lead to blurry vision. Usually, this problem resolves in a few weeks, but occasionally may require a second operation. Finally, some patients experience chronic irritation from the presence of the drain underneath their upper eyelid.
Q: Does a patient still need to use eye drops after a trabeculectomy?
A: Immediately after trabeculectomy you will no longer need to use your usual glaucoma medications in the operated eye. You will need to take new and completely different eye drops in the operated eye to prevent infection and help the eye heal properly. These new eye drops are discontinued after several weeks. If you are taking eye drops for your glaucoma in the other eye, you will need to keep using these drops in the usual way. If the eye heals properly and the surgery is successful, you will no longer need to take any eye drops to control the eye pressure.
Q: Can a trabeculectomy interfere with other medications?
A: Your doctor may ask that you stop taking pills which thin your blood (like aspirin, Coumadin, or Plavix) before the surgery. This minimizes the risk of bleeding during the surgery. These medications can be resumed after the surgery.
Q: What activities can a patient do after the trabeculectomy? Are there any restrictions on activities?
A: After surgery it is OK to read, watch TV, or do mildly strenuous activity such as walking. Usually, showering can be resumed a few days after surgery. Taking a bath or having your hair washed without getting the eye wet is permitted. For several weeks after the surgery you should not do any heavy lifting, bending over, straining, or other strenuous activity. Sexual intercourse, aerobic exercise, weight lifting, and swimming should be avoided for the first few weeks after trabeculectomy. Also, for a few weeks you should wear glasses or an eye shield during the day over your operated eye. At night you will need to wear an eye shield over your eye while you sleep. As long as you wear your eye shield, you may sleep on either side of your body. If you have constipation, the use of laxatives or stool softeners is recommended to prevent straining during bowel movements.
Q: Can a patient work after trabeculectomy?
A: Since the operated eye may be blurry for a few weeks following glaucoma surgery, you may not be able to perform tasks which require good vision in both eyes. Depth perception may be impaired as a result of the surgery. People whose jobs primarily require reading or paperwork can usually return to work fairly soon after their glaucoma surgery. Patients whose jobs involve manual labor such as heavy lifting will usually need to take several weeks off from their job.
Q: Well, that covers just about all my questions on diagnosing and treating glaucoma. I have a few more general questions if you don’t mind.
A: Not at all. Go right ahead.
Q: OK, I have a lot of tearing and irritation in my eyes. Is this because of my glaucoma?
A: Probably not. The fluid produced by the eye’s “faucet” circulates inside the eye and never reaches outside the eye. Glaucoma does not cause symptoms of burning, irritation, or tearing. These symptoms are usually caused by dry eyes.
Q: I’ve heard that dry eye is very common. What exactly is dry eye?
A: The surface of your eye is lubricated and protected by a thin layer of tears. This tear layer is produced by tear glands and spread over the surface of the eye every time you blink. Several factors contribute to dry eyes. You produce less tear fluid as you get older. This is particularly true in post-menopausal women. You blink less when you wear contact lenses, work in front of a computer, watch TV, or read a book. Blinking less causes the tear film to evaporate which exposes the surface of the eye. This causes pain since the surface of your eye is very sensitive. It also causes blurry vision since the surface of your eye must be perfectly smooth to focus properly. Dry eye can also be caused by taking decongestants and hormones. It can also be associated with certain autoimmune diseases. Dry eye cannot be cured. Dry eye is treated by using artificial tear drops or lubricant ointment and encouraging more blinking. In severe cases of dry eye prescription eye drops may be used to increase tear production.
Q: This may sound stupid, but is glaucoma contagious?
A: No. Glaucoma is not caused by any bacteria or virus and cannot be spread from person to person. You cannot “catch” glaucoma from someone else. Blood relatives of people with glaucoma, however, are at increased risk of developing glaucoma themselves and should be examined by an eye doctor.
Q: Can other people tell I have glaucoma?
A: In most cases of glaucoma, the front part of the eye looks perfectly normal. The parts of the eye which are abnormal in glaucoma, the optic nerve and the angle, are not visible to the naked eye.
Q: Why is glaucoma so dangerous?
A: Glaucoma is one of the few eye diseases without any symptoms. No pain. No redness. No blurry vision until it’s too late. Since early loss of side vision isn’t noticeable, you could be losing a large portion of your vision and not even know it. In this way, glaucoma is like a “thief in the night,” stealing a person’s vision without them ever knowing it. Glaucoma is a leading cause of blindness among older Americans. It is the number one cause of blindness among African-Americans.
Q: What can I do to prevent glaucoma from happening to me?
A: Currently there is nothing you can do to prevent glaucoma. The best chance of avoiding blindness from glaucoma is through detection at an early stage when it can be well controlled. Since glaucoma has no symptoms, it is important to have regular eye exams by your eye doctor. This is especially important if you are over the age of 60 or have any risk factors for glaucoma.
Q: Is glaucoma the same thing as having cataracts?
A: No. Glaucoma and cataracts are two different diseases. Losing vision from glaucoma is very different from losing vision from cataracts. Cataracts affect the central vision and cause symptoms of blurry vision, difficulty reading or driving, or glare in sunlight. Glaucoma, on the other hand, has no symptoms until it is very advanced. Loss of vision from cataracts is reversible. Cataracts can be removed with surgery and vision can be restored. The vision that’s lost from glaucoma, however, can never be recovered. Cataracts cannot be improved with eye drops, and they cannot be removed with laser surgery. Glaucoma, on the other hand, is first treated with eye drops and later possibly with laser surgery. Glaucoma surgery is done if these treatments fail to control the disease.
Q: Is it possible to have glaucoma and cataracts at the same time?
A: Many older people have cataracts as well as glaucoma because both diseases are more common with increasing age. If your cataracts are causing problems with your vision and you are taking many eye drops for your glaucoma or your glaucoma is very severe, your doctor may recommend doing surgery for glaucoma and cataracts during the same operation.
Q: Are glaucoma and macular degeneration related?
A: No. Glaucoma and macular degeneration are two different diseases. Like cataracts, both diseases are more common with increasing age. Both diseases cannot be cured. Glaucoma affects the side vision in its early stages. Macular degeneration affects the central vision. Because the central vision is used for reading and everyday tasks, people with macular degeneration have difficulties reading much earlier than people with glaucoma.
Q: How can glaucoma affect someone’s career? Can glaucoma affect their ability to provide for their family or prevent them from enjoying their hobbies?
A: Treating your glaucoma can affect your life in many ways. You need to take your eye drops every day. It needs to be a part of your daily routine, just like eating meals, sleeping, combing your hair, or brushing your teeth. You will have to adjust your daily routine in order to make it a habit to take your eye drops. Remember, no one else can take your eye drops for you. And no one else will suffer more if you lose your precious sight from glaucoma. Eye drops are a relatively safe form of treatment, but they can have side affects which can interfere with your daily activities. Treating glaucoma also means regular visits to your eye doctor. You may need to take time off from work to visit your doctor. If you need surgery for your glaucoma, you may need to be examined by your eye doctor several times within the first month after surgery. The vision in the operated eye may be blurry for several weeks after surgery.
Q: What do you tell your patients when they ask, “Doctor, am I going blind?”
A: Blindness is a very real concern to patients with glaucoma and their doctors. However, most people with glaucoma lead full and productive lives. If glaucoma is detected early and treated appropriately, useful vision can be enjoyed for many years. If, however, glaucoma is already advanced by the time it’s discovered, then the chance of losing vision during one’s lifetime is greater. If you have glaucoma, the best way of preserving the vision you have is to see your doctor regularly and take your medications as prescribed.
Q: OK, that wraps it up. Thanks for taking the time to answer all these questions -- I’ve learned a lot from our discussion.
A: My pleasure. I’m always happy to educate the public about glaucoma and eye disease.