About Glaucoma

What is Glaucoma?

Glaucoma is a progressive disease, which causes optic nerve degeneration over time. The optic nerve is the main nerve responsible for vision. It is like a cable connecting the eye to the brain. As the optic nerve degenerates, vision loss occurs. This loss may be very subtle at first, and therefore may not be noticed until much later in the disease. Like a "thief in the night", glaucoma damage may creep up on people without being noticed.

What causes Glaucoma?

There are many types of glaucoma with various causes. The most common types are inherited or run in families. This means that if you have a relative (especially a parent) who has glaucoma, you should be checked to see if you have any signs of early glaucoma. Some people with diabetes who develop retinal eye disease may develop neovascular glaucoma. Uveitis or eye inflammation can cause glaucoma as well. Some people are born with glaucoma.

If I have glaucoma does that mean I will go blind during my lifetime?

These days, due to improved screening and treatment modalities, most people do not go completely blind from glaucoma. The best way to prevent vision loss from glaucoma is to diagnose and treat it early in the disease process. It is strongly recommended that everyone, especially those who have a family history of glaucoma or any other risk factors, have a screening eye exam to rule out eye disease. This is important because unless you get tested, you may not realize you have glaucoma. Most forms of glaucoma are silent and rarely cause symptoms until the advanced stages. If you have already lost vision from glaucoma, working with your ophthalmologist and optometrist to monitor and stabilize your disease will be key in slowing down the progression of glaucoma and preventing more vision loss.

Now that I have been diagnosed with glaucoma, what can I do to prevent it from getting worse?

The best thing you can do is keep a positive and optimistic outlook. Glaucoma is a chronic illness which needs to be regularly monitored. With routine monitoring and management, most people with glaucoma do well. Make sure you follow-up with your optometrist or ophthalmologist and follow their instructions. If you are having problems with any of the treatments, let them know.

Eating a healthy diet including green leafy vegetables, exercising regularly and managing your other medical problems (particularly diabetes and high blood pressure) will help your eyes stay healthy as well. If you are a smoker, quit smoking. Smoking decreases oxygen to your eye nerves and makes them sicker. Sleeping with the head of your bed elevated to about 30º lowers eye pressure. If you have advanced glaucoma, extreme weight lifting or playing certain instruments (like a trumpet) would not be advisable since they may increase the pressure in your head and also in your eyes. Sleep apnea and low blood pressure at night can cause glaucoma to get worse. You should be checked for these if you have any symptoms or risk factors for them; they should be treated to prevent worsening glaucoma.

What are the key risk factors for glaucoma?

• High eye pressure
• Family history of glaucoma
• Increasing Age
• Race: African or Asian Descent
• Females > Males
• Vascular factors (affecting the circulation to the eye): (eg Migraines, Vasospastic or Raynaud's disease, low blood pressure, high blood pressure)
• Thin corneas (pachymetry measurement)
• Myopia (near-sightedness) - for open angle glaucoma
• Hyperopia (far-sightedness) - for narrow or closed angle glaucoma

Does glaucoma only affect older people? What are some of the types of glaucomas?

Glaucoma can affect all ages, from newborns to the very elderly. Newborns can be affected by congenital glaucoma which is a type of glaucoma that they are born with. Children or young adults can be affected by juvenile glaucoma. People diagnosed with glaucoma in their 30's and upward usually have other delayed onset types of glaucoma such as Primary Open Angle Glaucoma (POAG), Pseudoexfoliation (PXF) Glaucoma, Pigmentary Glaucoma, Acute or Chronic Angle Closure Glaucoma (AACG/CACG) and Mixed Mechanism Glaucoma. Glaucoma worsens with time and increasing age, and at a faster rate if left untreated. There are other types of glaucoma that are associated with diseases like diabetes, such as neovascular glaucoma (NVG) and rheumatoid illnesses, such as uveitic glaucoma. Glaucoma can also be caused by chronic use of steroids, known as steroid-induced Glaucoma.

Why is it important to lower eye pressure in glaucoma?

One of the main risk factors that can cause progression of glaucoma and vision loss is high eye pressure. Normal eye pressure runs between 10 and 21 mmHg. In patients with glaucoma, this pressure is often higher than 21 and needs to be lowered. However, not all patients with glaucoma have high eye pressures. This type of glaucoma is often called Normal Tension Glaucoma, but it is also considered as another form of Primary Open Angle Glaucoma. Even with this type of glaucoma, the best way to prevent progression of the disease is to lower the eye pressure sometimes to slightly subnormal range (eg. 7-9mm Hg). Really low pressures are not healthy either (eg. 6 or lower) since they can cause wrinkling of the inner eye layers, and poor vision as a result, along with other problems.

If eye pressure is high in glaucoma, wouldn't I be able to tell?

When eye pressure increases gradually, people often have no symptoms at all, apart from occasional eye discomfort or slightly foggy vision. Often these people are discovered to have high pressures on a routine eye examination. Having a routine eye exam is very important, since glaucoma is often a silent disease with no warning signs until the advanced stages when some vision loss has already occurred.

However, if there is a sudden rise in the pressure, which can happen with certain types of glaucoma (for example, angle closure glaucoma or neovascular glaucoma), there are symptoms of intense pain, headache, decreased vision and even nausea and vomiting. This type of problem needs emergent attention and anyone experiencing this should go to his/her local emergency department.

Many over the counter drugs advise not using them if you have glaucoma. Should I avoid all these drugs if I have glaucoma?

If you have narrow angles or angle closure glaucoma, then you should not be using these over the counter medications. However, if you have had laser or surgery to fix the narrow drainage canals, then it is usually safe for you to use them. If you are uncertain, check with your Optometrist or Ophthalmologist first. These drugs often have components in them that can cause dilation of the pupils. Dilation of pupils can cause the drainage canals to completely close in people who have untreated narrow canals (angles). If they close completely, this can cause the eye pressure to suddenly rise and cause pain, headache, loss of vision, nausea, and vomiting. If this happens, you should go to your nearest emergency department immediately.

How is glaucoma treated?

Glaucoma is treated by laser, eye drops or pills, and/ or surgery. Glaucoma is a lifetime disease that changes over time and needs to be monitored. Treatment usually has to be adjusted to manage the changes in glaucoma over time. People who have glaucoma often undergo various treatments and surgeries over their lifetime to control the disease. It is important to have regular visits with your Optometrist or Ophthalmologist to ensure that your treatment is working and keeping up with the disease.

Is Marijauna helpful in treating glaucoma?

Marijauna can lower eye pressure. However, the pressure lowering effect only lasts for 2-3 hours. Therefore, marijauna would have to be taken every 2-3 hours to be effective in a 24 hours period. As well, the THC, not the Cannabis component of marijauna causes pressure lowering. THC also causes psychotropic side effects. Marijauna is not used as a treatment for glaucoma since it needs to be taken too frequently. The numerous side effects and risks of taking marijauna to treat glaucoma do not outweigh the benefits. Other treatments which have been developed are safer, with less systemic side effects and more effective.