About Glaucoma |
Glaucoma is a family of diseases that all damage the optic nerve and produce a characteristic appearance of the optic disc, which is where the optic nerve enters the eye. This appearance takes on the look of “enlarged cupping” and is caused by the loss of retinal nerve fibers. Though it is often thought of as a “high eye pressure” disease many patients with it have what we consider to be normal eye pressure.
- The disease usually progresses slowly over years. However, about 15% of patients are “fast progressers.” Consequently we tend to do more frequent checks at the time of diagnosis and in advanced disease.
- Glaucoma is a progressive disease without a cure. Our goal is to slow it down so much that you are never bothered by the vision loss. However, sometimes the disease progresses despite all our efforts, and despite having low eye pressures. It is for this reason that frequent testing is required.
- It causes a characteristic pattern of visual loss measured by a visual field test. The vision loss usually starts in the periphery and slowly works its way into the center.
- It has a hereditary predisposition and it is common for an affected patient to have close relatives that also have the disease.
- It has NO SYMPTOMS until the disease is advanced, no blurred vision, no pain. In the early disease, patients have no way of knowing they are ill other than an eye doctor telling them so.
- Consequently, Glaucoma is referred to as “The Thief of Sight”.
- It is best detected by a dilated eye examination with detailed analysis of the optic nerve. Routine eye pressure checks (IOP) without dilation will fail to diagnosis a large percentage of cases.
- It is usually treated initially with prescription eye drops that lower the eye pressure. In patients with “Low-Pressure” Glaucoma we still lower the pressure to treat the disease.
- Sometimes a laser treatment called Argon Laser Trabeculoplasty (ALT) or Selective Laser Trabeculoplasty (SLT) is used to additionally lower the pressure. These procedures do not always work and when they are effective they last only three to five years.
- In cases when the pressure cannot be controlled or when vision loss occurs despite medical and laser treatments, a major surgery called trabeculectomy or tube shunt may bedone. These surgeries are effective but carry significant risks, and are only used when other methods fail.
- Even though you may not need eyeglasses, you could still be diagnosed with Glaucoma.
Glaucoma usually occurs in patients over 50 years of age, though we occasionally diagnose children and young adults with it.
Types of Glaucoma
Primary Open Angle (POAG)
- This is the most common type in Caucasians.
- Characterized by high intraocular (eye) pressure.
- Treated with pressure-lowering eye drops, a special type of laser surgery or major surgery to form a new drainage channel in the eye.
Normal Tension (NTG)
- The intraocular pressure is normal.
- Strong correlation to sleep apnea, a sleep disorder in which patients cease breathing while asleep.
- Treated the same as POAG.
Narrow Angle (NAG)
- Most common in patients of Asian descent.
- More common in farsighted patients.
- Symptoms may include headaches when in the dark.
- Caused by restricted path for outflow (narrow anterior chamber angle) of eye fluid (aqueous).
- Treated with a special type of laser surgery.
- Caused by pigment clogging up the “drain” (trabeculum) of the eye fluid (aqueous).
- Identified by a deposit of pigment on the back of the cornea (Krukenberg spindle).
- This can be worse after exercise or exertion. Symptoms involve temporary blurred vision or headache.
- Treatment includes a variety of laser procedures (laser trabeculoplasty) and sometimes pressure-lowering prescription eye drops.
- Caused by a systemic condition that causes build-up of an abnormal material (exfoliative material) in the drain of the eye (trabeculum).
- Coats the lens and other eye structures.
- More difficult to control than some of the other types.
- Makes cataract surgery more difficult.
- Secondary to another condition that reduces the normal flow of blood to the tissues in the eye.
- Lack of oxygen (hypoxia) causes the tissues to release chemicals (vascular endothelial growth factor – VEGF) that promote the growth of new but abnormal blood vessels.
- These new defective blood vessels leak serum or blood into the tissues and results in formation of a fibrous scar tissue. The scar tissue contracts and the resulting traction may detach the retina and cause further bleeding.
- Relatively common in diabetes, retinal vascular occlusions (central retinal vein occlusion, central retinal artery occlusion, ocular ischemic syndrome).
- Treatment often includes laser treatment of the retina (pan-retinal photocoagulation) and injections of anti-VEGF drugs like Avastin or Lucentis.
The most common method of treating glaucoma is with prescription eye drops that are put in the eye. Newer medications only need to be put in once a day, but we often must add some other drops when the eye pressure is not sufficiently lowered.
Some of the important considerations for glaucoma eye drops are:
- Remember to put your drops in every day. This is the single most important thing you can do to preserve your vision.
- We recommend you use artificial tears 3 or 4 times per day when taking glaucoma eye drops. This will reduce or eliminate the dry eye symptoms many patients get from the prescription medications.
- Do not take any other eye drops, such as artificial tears, within 10 minutes of the glaucoma eye drops. This will prevent the dilution of the prescription drops.
- Use the Punctal Occlusion Technique when you put in any prescription eye drops. To do this, put gentle pressure with your finger in the corner of your eye next to your nose and hold it there for at least 30 seconds. Do this as soon as the drop goes into your eye and it will minimize the drops leaving your eye through your tear drains into your throat. This both increases the amount of medicine getting into your eye and reduces the risk of medicine being absorbed into your general circulation.
- It is very important to keep your appointments to monitor your eye pressure. Sometimes the glaucoma medication loses effectiveness, if it does you will not know unless your keep your appointment.
Glaucoma has historically been considered to be the least responsive eye disease to nutritional treatment. At this time wedon’t have any large prospective, double-blind studies showing significant benefit from nutrition and probably never will due to the enormous expense of such trials.
However, there are a few studies that have indicated some natural remedies that may help.
- Two new retrospective studies dealing with the effects of nutrition on glaucoma were recently published in ophthalmology journals. Retrospective studies do not prove a causal relationship, however, they did demonstrate a strong association, showing that patients with diets high in fruits and vegetables were about 70% less likely to develop glaucoma.
- Small studies show that omega-3 fatty acids somewhat lower intraocular pressure (IOP).
- Ginkgo biloba, commonly used to increase blood flow to tissue and improve memory, has shown interesting abilities to protect the nerves in some studies.
- Curcumin (Curry) has been shown in small studies to be helpful.
In addition to the helpful nutrition, there are a few things that may increase your eye pressure, that you will want to avoid;
- Coffee has been shown to increase eye pressure a small amount.
- Wearing a necktie with the top button buttoned will raise your eye pressure a couple of points.