Chat Highlights
Angle-Closure Glaucoma
June 7, 2000

Norma Devine, Editor

On Wednesday, June 7, 2000, Dr. Jonathan Myers, a glaucoma specialist at Wills, and the glaucoma chat group discussed "Angle-Closure Glaucoma." 

Moderator:  Welcome back, Dr. Myers.  Shall we begin the discussion of  angle-closure glaucoma?

Dr. Myers:  Thanks.  Hello everyone.  Angle-closure glaucoma is an interesting topic.  I know some of the folks here have first-hand experience.

P:  Are there different types, such as  suspect, narrow, and closed?

Dr. Myers:  Yes, you're right.  Angle-closure is not always all or none, and can develop gradually.

P:  Does a person with open-angle glaucoma ever have angle-closure? 

Dr. Myers:  Patients with open-angle glaucoma still may occasionally develop angle-closure and need to be monitored for this during their regular check-ups.

P:  What is the usual course of treatment for someone with narrow angles and elevated pressure?

Dr. Myers:  Someone with narrow angles and mildly elevated pressure typically first undergoes iridotomy (making a tiny hole in the iris to allow the aqueous to flow out of the eye, thereby reducing the pressure).  If the iridotomy is successful, the pressure may or may not drop.  If the pressure does not drop, eye drops are usually used.

P:  After an iridotomy, is the glaucoma still defined as being angle-closure?  I have what is called creeping angle-closure glaucoma. 

Dr. Myers:  Sometimes people undergo a laser iridotomy, or a laser hole in the iris, to help prevent worsening of a narrow angle.  Creeping angle-closure is one type that the laser often works to stop the development of further closure.  After the treatment, the glaucoma may still be called angle closure, depending on if the laser fully improved the opening of the angle, or just helped to stabilize it.

P:  Please explain creeping-angle glaucoma.  

Dr. Myers:  The angle is the area through which fluid drains.  In creeping-angle closure, the angle slowly scars closed over years.  In acute-angle closure, the angle closes off in minutes or hours, with a sudden painful rise in pressure.  In early narrow angles, the laser iridotomy may fully restore a normal, open angle.  Most people in America have the open-angle type glaucoma.  In Asia and Alaska, the narrow angle is more common.

P:  The angle can close slowly, too, can't it?  Mine did -- at least I think it did.

Dr. Myers:  The angle can close slowly, over even decades in some cases.

P:  Can scarring from where the angle is chronically closed cause a blind spot?

Dr. Myers:  The scarring causes blind spots if it makes the pressure go up, causing nerve damage leading to vision loss.  The scarring doesn't directly affect the field of vision.

P:  After an iridotomy, can I still get an acute attack?  My IOP had stabilized at 18, but now it is up to 22.

Dr. Myers:  It is very, very rare to have an attack of angle-closure glaucoma after a successful iridotomy.

P: I had an iridotomy three years ago.  It seemed to have stabilized the IOP until recently.  But the pressure has started going up again.  When I am evaluating treatment options, should I look at options for open or closed-angle glaucoma?  Now that glaucoma medications are no longer working for me, my doctors are considering trabeculoplasty.  Will that work for me?

Dr. Myers:  It may be that your angle is open enough to allow successful trabeculoplasty.  Most people who have treated angle-closure respond to the same treatments for open-angle glaucoma.  One exception is that ALT (argon laser trabeculoplasty) can't always be used if the angle is closed.

P:  If a patient can pass provocative tests with no rise in pressure, is the angle-closure cured?

Dr. Myers:  Provocative tests help to show a successful treatment, but they are not 100% accurate.

P:  Is it true that those who have surgery for closed-angle glaucoma are not at risk? 

Dr. Myers:  Most people who have had cataract or glaucoma surgery are not at risk for attacks of angle-closure glaucoma.  Rarely, chronic angle-closure glaucoma can still develop.

P:  How soon should a person suffering an acute attack be treated?

Dr. Myers:  People suffering with an acute attack of angle-closure glaucoma must be seen immediately by their eye doctor or in an emergency room.

P:  What is the effectiveness of trabeculoplasty for people like me who have had an iridotomy?  How many times can it be repeated safely?  Does cataract surgery help?  

Dr. Myers: Trabeculoplasty has roughly an 80% response rate, in which successfully treated patients have a 20 to 30% drop in pressure.

P:  What is a trabeculectomy?

Dr. Myers:  A trabeculectomy is an operation to lower the intraocular pressure in glaucoma.  It creates a small channel to allow fluid to drain from inside the eye, to be absorbed in the 'bleb', a blister formed under the upper eyelid.

P:  How long are trabeculectomies usually effective?

Dr. Myers:  Trabeculectomy, if successful past the first year, may last 5, 10, or even 15 years.  The success of trabs depends in part on the patient,  the type of glaucoma, previous surgery, medications, and other factors.

P:  I'm 19 with juvenile glaucoma and have had two trabs in the left eye.  It's fine now, even without eye drops, but have patients in similar situations had to have surgeries in the future or return to using drops?

Dr. Myers:  I'm glad you're doing well now following surgery.  Often after surgery people have good pressure control for many, many years.  At the current pace of research, who knows if you'll need drops, surgery or some totally new treatment in the future?  Trabs may last a long time.

P:  What is preferable, more medications (I am on  three kinds of eye drops now) or trabeculoplasty?

Dr. Myers:  For some folks trabeculoplasty may allow a reduction of meds, but it really depends on the details of your eye.  Three  meds are a lot when you have to take them day in and day out.  But, if they do the job, it's worth it.

P:  Are people with a closed angle affected more by over-the-counter medications and steroids than open-angle patients?  I've been told the warnings on the over-the-counter medications do not apply to me, because I have open-angle glaucoma. 

Dr. Myers:   That's a good point.  Cold and allergy medicines can trigger an attack of angle-closure glaucoma in those who are at risk.  Steroids can increase eye pressure gradually in some people, but that's an open angle type glaucoma.

P:  It seems like my eye feels a little different after taking allergy decongestants, but I would not consider it an "attack."  Is it possible the decongestant could drive up my pressure enough that I could sense a difference?

Dr. Myers: It's unlikely that what you're feeling is the pressure.  Sometimes the meds can affect the sinuses with similar sensations.  It might be wise to have it checked, though.

P:  My doctors told me not to use antihistamines.

Dr. Myers:  A person with a narrow-angle is often best off without antihistamines, which can sometimes further narrow the angle.  Sometimes the doctor can check the angle before and then after antihistamines to see if  the angle changes.  The anti-histamine effect is temporary, but could be serious if it triggered an attack.

P:  My eye doctor and my allergy doctor had to discuss my situation. 

Dr. Myers:  Great point.  It's always a good idea to get your doctors talking to each other and writing to each other. 

P:  Should people with closed-angle avoid dark places like movie theaters, where pupils dilate, which could bring on an acute attack?  

Dr. Myers:  Life's too short to avoid all that.  Once treated, people with angle-closure glaucoma can safely do all those activities.

P:  Is there always cornea clouding during an acute-angle attack?

Dr. Myers:  Early in an attack,  the cornea may be clear.  It depends on how high the pressure is, and how healthy the cornea is.  Cornea clouding from pressure is one source of visual blurring.

P:  What are the symptoms of an acute-angle attack?

Dr. Myers:    Classically,  angle-closure attacks start with pressure around the eye, almost like a sinus headache.  This pressure may build into a severe headache, accompanied by blurry vision and a red eye.

P:  What about the vision?  Is that affected and if so, when?  

Dr. Myers:  People may notice halos around street lights during an attack.  As the attack worsens, they may become nauseated and even vomit.  Keep in mind, though, that other things, like cataracts, may also cause halos.  

P:  And this happens over what time period?  Hours?  Minutes?

Dr. Myers:  The process can develop over 20 minutes to several hours, often occurring in the evening.

P:  I thought those were my migraine symptoms.  What can be done in an emergency room to help an acute-angle attack?   

Dr. Myers:  Angle-closure attacks are treated with medicines to reduce the pressure, including eye drops and/or pills, or intravenous medicines.  Migraine symptoms may be somewhat similar, but your doctor may be able to tell the difference from the details of the symptoms and from your eye exam.

P:  I had mannitol intravenously once.  My arm felt like it was going to fall off.  I was yelling.

Dr. Myers:  Intravenous mannitol is a strong medicine,  which draws fluid out of the eye to reduce the pressure.  Did the mannitol lower your pressure and reduce the pain?

P:  Yes, it did and eventually I could see again.  The pain lingered on and my eye still hurts right in the front where it was scarred.

P:  Why did mannitol affect your arm like that?

P:  I think it was because the mannitol was very thick.  When the numbness reached my shoulder, I said stop it NOW.  I was dying of thirst, but they wouldn't let me drink.  

Dr. Myers:  Mannitol is concentrated, so it sometimes burns when it goes in.  If the IV is not in perfectly, it may feel worse.

The following are general glaucoma questions and anwsers from the open forum with Dr. Myers that followed the discussion on angle-closure glaucoma.

P:  If my IOP is around 22, is it better to let it alone or increase the medications?  

Dr. Myers:  Pressures of 22 are great for some people and terrible for others.  It depends on the amount of nerve damage and the pressure at which the damage was done.  Some people's eyes seem more sensitive to eye pressure than others'.

P:  My IOPs at last reading were 20 before pupil dilation and 22 after pupil dilation.  Why did they go up?

Dr. Myers:  Dilation may affect the fluid outflow from the eye, changing the pressure.   For most people, that effect is mild and short.  People with narrow angles that haven't been treated may develop severe high pressures following dilation.  

P:  If my IOPs are 21 and 19 is it okay to be off drops?

Dr. Myers:  IOPs of 19 and 21 can be good or bad. It really depends on the details of your particular eyes. You should talk about that with your eye doctor.  

P:  After I use eye drops for six months, can  my eyes manage the pressure themselves? 

Dr. Myers:  For most people, once the drops stop, the pressure goes right back up.

P:  My wife had lower pressure, but just recently it went up to 22 on two separate measurements. Glaucoma tests are negative. Should she take preventive measures?

Dr. Myers:  A pressure of 22 is a bit higher than average, but may be fine or terrible, depending on the other issues.  If everything else looks good (nerve, angle, visual field), it's probably fine to watch at a pressure of 22, with a doctor's supervision.

P:  Will annual tests for her be enough to catch any developments?

Dr. Myers:  For most people with otherwise healthy eyes, yearly checkups are a good bet for safety. That's what I usually recommend.   

P:  Glaucoma is not uncommon, right?

Dr. Myers:  Glaucoma affects about one percent of  the population, with about five times more being at significant risk and needing to be monitored.

P:  I heard they under-estimated the number of  people under 40 with glaucoma.  It that true?

Dr. Myers:  Glaucoma is more common the older we get. It used to be thought of as very rare under age 40, but recent studies seem to suggest that it can be picked up earlier.  Especially in African-Americans, glaucoma is more common at younger ages.

P:  Do you think people with no nerve damage and no visual field loss but IOPs above 22 should be treated?

Dr. Myers:  Studies seems to suggest that people with normal nerves and fields but elevated pressures may be followed safely with close monitoring, if their pressures are in the mid 20's.

P:  What are the chances of getting glaucoma if  someone in the family has it?  

Dr. Myers:  Having someone in your family with glaucoma increases your chances of getting it two to four times, but remember that's only two to four times a one to two percent risk. 

P:  Then those people could be monitored but not treated, right?

Dr. Myers:  Yes,  those people often can be monitored but not treated, if they and their doctor agree.  An exception might be someone with a strong family history of blindness from glaucoma.

P:  My doctor said that if my pressure goes above 26, he would start treatment.  Does that sound right to you?  There are no field problems or nerve damage yet.

Dr. Myers:  That  sounds reasonable, depending on the details of your case.  The key point is that someone is watching your nerves, fields, and pressures carefully and accurately with all available techniques.

P:  How often should visual fields be tested? 

Dr. Myers:  Usually we check visual fields about once a year.  We check more often if there is a concern things are changing;  a bit less often if things have been stable for a long time.

P:  Isn't it true that many people go for years with IOPs in the 30's and  never suffer damage?

Dr. Myers:  The odds of damage over time increase dramatically at pressures of 30 and above.  Some people can be okay for years, but many will get worse or be at risk of vision loss with pressures of 30 and above.

P:  I have ICE syndrome that causes my glaucoma.  I was told the cells of my cornea have clogged my drain.  Is my glaucoma still considered open-angle?

Dr. Myers:  ICE syndrome may start as an open-angle glaucoma, but later the sheets of cells often  pull the iris closed over the angle.

P:  Since I have ICE syndrome, do I need to worry more about my parents and future children developing eye problems like mine?   

Dr. Myers:  ICE syndrome, luckily, tends to affect only ONE eye in a person, and tends NOT to run in families.

P:  I think people in this group would agree that if a patient has doubts about a diagnosis, he or she should get a second opinion.

Dr. Myers:  You bring up a good point.  A second opinion is never a bad idea. It often helps reassure both patient and doctor that they are on the right track.

P:  My doctor treats glaucoma, but he did not do a fellowship in glaucoma during his training.

P:  I think those doctors not directly involved in the field of glaucoma are often not up on the latest information on treatment.

P:  We have had had two people come to this chat room who were being treated for normal-tension glaucoma.  It took a lot of  time and effort to persuade them to get second opinions.  Finally, they found out they didn't have any kind of glaucoma. 

Dr. Myers:  Some patients see a specialist just for confirmation of the original diagnosis, and then are followed routinely by their regular eye doctors.  I'm happy to see new patients.  You should also feel free to check in with any of the glaucoma doctors at Wills.

P:  I suggest seeing a specialist outside your own doctor's circle of colleagues.  As some here know, I had subtle but powerful side effects from beta blocker drops.  I didn't suspect the beta blocker might be causing a problem.  

Dr. Myers:  That's a good point about the side effects of  eyedrops.  Often, people don't realize the problem is the drops.

P:  Could riding roller coasters cause problems for patients with angle closure or open angle glaucoma?

Dr. Myers:  Roller coasters are pretty safe.  Bungee jumping has been associated with some significant eye injuries, though.

P:  The G-force on riders of some of the new coasters is more than on astronauts during lift-off. 

Dr. Myers:  Sounds like I've got to try one of the new roller coasters.

P:  My Dad said he read an article about Viagra being used to treat macular degeneration.  Have you heard about that?  

Dr. Myers:  No.  I have not heard about Viagra treatment for macular degeneration.  Interesting.

P:  Does neuro-protection research offer real hope for us?

 Dr. Myers:  There is a lot of new data out on neuro-protection in animals.

P:  I had a GDX nerve fiber analysis, and my doctor said the nerve fibers were normal.  I thought this was good, but Dr. Wilson seems to think the GDX is not that good a tool.

Dr. Myers:  The GDX is helpful, but I agree with Dr. Wilson.  It's not perfect.   It's one of many measurements that need to be taken into account.

P:  There's lots of good information about all aspects of glaucoma and treatment on the Glaucoma pages. 

Moderator:  Good night Dr. Myers.  Thanks for joining us.

Dr. Myers: Good night.

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End of highlights for the June 7th chat. Click here to read more about angle-closure glaucoma.

On June 14th, Dr. Rick Wilson discussed "Coping with Vision Loss" in the Chat room.  Click here for highlights of that meeting.

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