Text Size Normal Text Sizing Button Medium Text Sizing Button Large Text Sizing Button Text Contrast Normal Contrast Button Reverse Contrast Button Switch to Spanish Language Press Room Contact Us Sitemap Sign In Register
Link to Homepage About BrightFocus
Donate Now Get Involved  
Alzheimer's Disease Research Macular Degeneration Research National Glaucoma Research

Stay Informed: Medical and Research Updates
Connect With Us!


Ask an Expert about Glaucoma

Latest Questions and Answers
I am a 74-year-old female, and at times I have forgotten the exact time that I put the first drop of Combigan in my eyes, which my doctor recommended that I use only twice each day. If I accidentally used the drops less than 12 hours apart, was that harmful to my eyes? [ 09/07/12 ]

No, it is not harmful if you have spaced it less than 12 hours apart. But, like any medication, the dosing is designed to maximize its effectiveness, based on how long it lasts in your system. Of course, each patient is unique and different, so I would not worry too much about the scenario that you described. It is more important that you are using the medication consistently. If you can remember to space it 12 hours apart, that is ideal, but again, it is more critical that you take both doses in a given day.

I was diagnosed with Posner-Schlossman syndrome in January 2012. In a routine test, the eye pressure in both eyes was measured as 40 and 45. Two days later, the pressure was measured at 17 and 21 without any medication. Since that time, I have been applying Combigan eye drops two times daily. My field vision tests were normal but the CD ratios are high (0.8) in both eyes. What are the chances of successfully controlling my glaucoma and protecting my vision? [ 07/09/12 ]

Thank you for your question and I am sorry that you are going through all of this. The eye doctor's goal is to identify glaucoma before you, as a patient, ever notice any changes. While it sounds as though your visual fields are full, the optic nerves may have early damage from the glaucoma (hence the increased cup to disc ratio). Therefore it is important to get the pressure lower so that further optic nerve damage and vision loss does not occur in the future. Eye doctors use three different methods to decrease the pressure:

  • medicated use medicated eye drops (such as Combigan)
  • laser treatments
  • surgical methods to lower the intraocular pressure.

Your doctor will follow the intraocular pressure, vision, visual fields, and the appearance of the optic nerves to see how your eyes respond to the treatment and ensure that you stay at your goal intraocular pressure. If the pressure is not reduced enough or your doctor ever notices advancement in your glaucoma, he or she will add more medications or use laser or surgery to help lower the intraocular pressure further.

If someone is diagnosed with glaucoma very early, the goal is to begin treatment and hopefully prevent the person from ever noticing any changes in vision. Unfortunately, doctors cannot predict if or at what rate a patient will lose vision because of the glaucoma. In some cases, despite the best efforts, doctors cannot stop the progression of the glaucoma and patients do eventually go blind, but this is the minority of patients. It will be important that you continue to visit your glaucoma specialist regularly, follow their advice, and maintain your eye pressure at the appropriate goal for the best chance of maintaining vision throughout the rest of your life. I wish you the best of luck.

I was born with cataracts, which were removed (along with my lenses), leaving me with decent vision. I was then diagnosed with glaucoma at age 7. When I was 15, I had a trabeculectomy in my right eye, and then a tube implant in the same eye at age 19. I’m 33 years old now. I also recently had a cornea transplant in the right eye because it decompensated. Somewhere amidst those glaucoma surgeries (10+ years ago) I lost functional vision/acuity in my right eye although the tube has kept the pressure low. My left eye has been fairly stable with eye drops until recently, but the pressure is creeping up and I may require surgery in that eye. I’m obviously nervous to lose functional vision in that eye following surgery, and would like to know the impact that modern tube surgery has on vision. What should I should I expect? Also, when medications are changed, how long should it take for the new medication to start lowering pressure? [ 07/07/12 ]

Thank you for your question. I am sorry that you are having so many problems with your eyes. It sounds as though you have quite a complex history. Unfortunately, given the complex nature of your problem, the fact that I have not examined your eyes, or the fact that I have not seen any of the test results from previous exams, it will be nearly impossible for me to give a completely accurate assessment; however, I can give you some general thoughts. These are questions that you should directly ask your surgeon prior to your glaucoma surgery.

First, ask about the impact of modern tube surgery on vision. Any time eye doctors discuss surgery, they should talk about the risks, benefits, and alternatives to each surgery that is recommended. In the case of glaucoma tube surgery, they discuss things like the risks of bleeding, infection, pain, the pressure not being low enough (requiring further surgery or medications), the pressure being too low (requiring further surgery or medications), decrease in vision, or loss of the eye. While these are some of the risks, this is not meant to be inclusive because each case is different. While these side effects can occur, the more serious complications, such as vision loss, happen in a minority of patients. Most patients notice only minimal changes (if any) in vision. If vision does change, the vision loss can occur immediately after surgery because of the stress the surgery places on the eye. In addition, simply inserting a tube into the eye can cause the cornea to change its refraction slightly; therefore, a glasses prescription may be needed (or it may need to be changed) to obtain the best visual acuity. Finally, some patients can notice some double vision because the glaucoma tube implant is near the muscles of the eye.

In your particular case I do not think this will be a problem given the poor vision in your left eye. Some vision loss may also happen later in life. Often a glaucoma tube, if placed into the anterior chamber, can cause cornea decompensation and the need for a cornea transplant. These would be the primary reasons for a change in vision after the glaucoma tube is implanted. Again, overall, most people do not notice much change in vision, but it is something that you should discuss with your doctor.

Finally, you asked about the length of time it takes for glaucoma medications to take effect. In most cases you can tell if a medication is working within a few days; however, there are a few medications, such as prostaglandin analogs, that may take a few weeks to have their full effect. I hope this helps and I wish you the best of luck.

I’m 49 years old and nearly three years ago I was told that I have advanced glaucoma in my left eye. I have pretty much tried all classes of eye drops for glaucoma, including some combination drugs, without sufficient eye pressure reduction. A laser procedure was tried but there was no significant effect at all. I eventually received a trabeculectomy in October 2010, which initially decreased the eye pressure to 13-14; however, the readings went back up to 18-20 a few months after the surgery, so the doctor tried Lumigan and Brimonidine. The eye pressure was kept around 18, but starting earlier this year the irritation and redness of my left eye got worse and increased over time. [ 07/05/12 ]

My ophthalmologist finally told me to stop all eye drops and prescribed oral methazolamide. I have not started on the pills yet as I'm very nervous about all the potential side effects. Is there data concerning the percentage of patients that experience severe side effects from this drug? What are the long-term health effects from taking methazolamide?

I am sorry to hear about your intolerance of eye drops and your glaucoma. Methazolamide is certainly an option, and for glaucoma patients who do not desire to have surgery (which is still an option for you), eye doctors sometimes offer them long-term methazolamide treatment, if it is tolerated.

As you know, many medications have side effects, and when you read the package insert of any medication, the list of side effects can be quite daunting. Methazolamide is typically better tolerated than the other oral medication in the same class, called acetazolamide. Some common side effects of this class of medication (carbonic anhydrase inhibitors) are: nausea, loss of appetite, change in taste, diarrhea, frequent urination, dizziness, and tiredness. These often improve with time. Other side effects that are more worrisome include blood in the urine, numbness or tingling of hands/feet, painful urination, sudden decrease in amount of urine, and ringing of the ears. There are also other rare side effects that are more serious, including a very serious (but also very rare) allergic reaction or decreased blood cell production.

I cannot give you a strict percentage of patients who have these side effects, but I can tell you that as long as you and your doctor monitor any changes after you begin therapy, the drug can always be stopped if you are experiencing intolerable side effects.

As for your question about long-term health effects, unfortunately that has not been well-studied; however, many of these side effects can be monitored and are related to the dose you are taking. One option for you is to start with a low dose (discuss with your ophthalmologist first) and then increase the dose upwards if the eye pressure is not low enough and you can tolerate the medication.

I am a glaucoma patient who had trabeculectomy surgery on both eyes. I later developed a cataract, which was removed. I was using Xalatan and Cosopt eye drops before the cataract surgery, and would like to know if I can still continue these medications? [ 11/13/11 ]

That is a great question. The answer often depends on the doctor doing the surgery. If possible, I will often times have my patients stop their prostaglandin analog (Xalatan, Travatan, Lumigan, or generic) a few days prior to cataract surgery because of a slight increased risk of swelling in the retina (called cystoid macular edema) after cataract surgery when you are on those medications.

Often the choice of whether or not to restart the medication after surgery is dependent on what the pressure in the eye is after cataract surgery. There has been some interesting new data that shows there is an approximate 2 mmHg drop in intraocular pressure that lasts for about two years after cataract surgery (there is not a full understanding of why this happens, but many researchers are currently looking into it). If the pressure has dropped sufficiently after the cataract surgery, it may not be necessary to restart the prostaglandin analog (Xalatan in your case) unless the pressure goes up again above your goal intraocular pressure. In other cases, even if there is a small drop in pressure, it may not be low enough to achieve your goal intraocular pressure, so the doctor will likely restart all of the glaucoma medications after a certain time period after surgery. Again, this is all dependent on the doctor's preferences and how your eye responds to the cataract surgery. Keep your regularly scheduled appointments and the doctor will monitor your pressure and make adjustments to your glaucoma medications accordingly. I wish you the best of luck

I am living in Japan and seeking SLT surgery to lower my eye pressure (it is between 18 - 20 mmHg). My ophthalmologist states that SLT can cause a sustained rise in eye pressure and does not think it is called for unless my visual field is noticeably worsening. All the literature that I am reading seems to indicate that it is a very safe procedure with few side effects. I received a second opinion from another doctor and was told the same thing. How common is a sustained rise in eye pressure as a result of SLT laser surgery? [ 11/11/11 ]

Thanks for your question. Of course it is difficult without examining you to tell if you should have SLT, but I can address your questions about eye pressure rises after SLT. While I certainly always warn patients of this risk when I talk with them about this procedure, it is generally infrequent, on the order of 3 - 5 percent, and it is not usually sustained. I have heard a few anecdotal cases of sustained eye pressure rises requiring surgery, but these situations are uncommon. There are also several maneuvers your ophthalmologist can do to minimize the risk of an eye pressure spike with SLT. I always give my patients a drop of apraclonidine (or brimonidine) before the procedure to reduce the risk of an eye pressure increase. I titrate the laser power so that I am using the minimum amount of energy to achieve an effect. I usually treat 360 degrees of the drainage system, but some ophthalmologists will only treat 180 degrees to minimize an eye pressure spike, although to my knowledge this has not been definitively shown to be of benefit. I also always have my patients wait 30 – 60 minutes after the procedure so that I can re-check the eye pressure. If there has been a spike, we control it with medications and then re-check the pressure again. Of course, one must weigh the risks and benefits of laser surgery, but I would say that overall SLT is a relatively safe procedure. I have not discussed all of the side effects of the procedure here, but you should have a conversation with your surgeon about the risks, benefits, and side effects before you proceed.

I have been using Xalatan for six months and my sleeping habits are not consistent. How important is it for me to take the drops before bedtime? Can I take them when I do not plan to sleep? I may go to bed at 8 p.m. one night and midnight or later the next night. What should I do? [ 11/09/11 ]

Thanks for your question. I think a lot of patients run into your dilemma. The reason that Xalatan is dosed at bedtime is because it begins working 3-4 hours after instillation, peaks at 8 -12 hours, and persists for 24 hours. Because we know that eye pressure is highest in the morning, taking the drop at bedtime puts you in a situation in which the drug is most likely to be peaking at the time when the eye pressure is also peaking. The most important thing is for you to be consistent about taking your drops, so if it is easiest for you to remember to put them in right before you go to bed, then that is what I would recommend. If, however, you know that you will not be going to bed until midnight or later, and you can remember to take the drops around 9 p.m., then it is reasonable to do schedule it then. Alternatively, if you go to bed at 8 p.m., I would not set an alarm clock to wake yourself up and take the drop at 10 in the evening! I hope this helped to answer your question.

I would like to find a glaucoma expert in Athens, Greece who can use a laser to treat narrowing of the cornea. Do you have any suggestions for how to find such a person? [ 09/24/11 ]

Thank you for your question. I assume that you mean that you would like someone to use a laser to treat you for narrowing of the drainage angle, and not the cornea. While I personally do not know any glaucoma specialists that are in Athens, Greece, I might suggest contacting the Athens University Department of Ophthalmology. The department may be able to recommend someone in the area for a consultation.

Items 89 - 96 of 543  Previous11121314151617181920Next

Disclaimer: The information provided here is a public service of the BrightFocus Foundation and should not in any way substitute for the advice of a qualified healthcare professional; it is not intended to constitute medical advice. Please consult your physician for personalized medical advice. BrightFocus Foundation does not endorse any medical product or therapy. All medications and supplements should only be taken under medical supervision. Also, although we make every effort to keep the medical information on our website updated, we cannot guarantee that the posted information reflects the most up-to-date research.

Some of the content in this section is adapted from other sources, which are clearly identified within each individual item of information.

Last Review: 04/28/13

YouTube Twitter YouTube Shop for a Cause Connect With Us Pinterest Google+