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Glaucoma - The Facts

Glaucoma Causes and RisksGlaucoma Screening and TreatmentCommon Symptoms and Complications of GlaucomaTreatments for GlaucomaThe Outcomes of GlaucomaOther Changes to Make


When my eldest mouse (at the time) was diagnosed with glaucoma I was a little surprised – glaucoma was something my granny had, not my mouse! After I got home from the vet I looked up medical sites on the Internet that would explain what exactly glaucoma was and what it would do to Whiskas since she could not survive the anaesthetic she would need in an operation to remove the eye. The following information is a collection of what I found that I hope may help others who experience the same or similar problems.

What is Glaucoma?
One of the leading causes of blindness, glaucoma is an eye disease in which the pressure in the eyeball increases, damaging the nerve of sight (the optic nerve) and causing loss of vision. Elevated intra-ocular pressure (IOP) occurs when the clear fluid that nourishes the tissues of the eye does not drain properly, causing fluid build-up and subsequent pressure. Over time, elevated IOP will damage the optic nerve and cause vision loss. Initially, the loss of vision affects only the extreme edges of the field of vision. However, if the raised pressure is not treated, the impairment of vision spreads to include the whole field of vision and can cause blindness. There are also rare instances when glaucoma can occur without elevated IOP.

Contrary to popular belief, glaucoma is not a disease limited to the elderly. There are several types of glaucoma:

  • Open-angle(narrow-angle) - the most common form of the disease, open-angle glaucoma is so named because the angle (between the cornea and the iris) where fluid is supposed to drain from the eye is open, but the fluid drains too slowly.
  • Closed-angle - closed-angle glaucoma occurs when the angle is blocked by part of the iris and fluid cannot drain from the eye.
  • Normal (or low)-tension - normal-tension glaucoma occurs in patients with normal IOP and is treated in the same way as open-angle.
  • Congenital - congenital glaucoma occurs when a child is born with defects that slow fluid drainage from the eye.

The front part of the eyeball is filled with a watery fluid called the 'aqueous humour'. It is continually produced and drains from the front of the eye through a small channel. An increase in pressure can result either from too much fluid being produced or from too little draining away. Glaucoma is almost always due to the latter.

Glaucoma Causes
Glaucoma is caused by fluid build-up within the eye, which (except with normal-tension glaucoma) eventually leads to elevated intra-ocular pressure (IOP). Glaucoma can also occur due to illness, eye injuries and steroid use.

Glaucoma Risks
There are several groups of people that have an increased risk of developing glaucoma. They include African-Americans over the age of 40, diabetics, anyone over the age of 60 or who has a family history of the disease, ocular hypertension (high intra-ocular pressure) patients, steroid users and patients who have had a previous eye injury.

There are two sorts of glaucoma: gradual onset (chronic glaucoma) and sudden onset (acute glaucoma). Chronic glaucoma usually has no symptoms until an irreversible loss of vision has occurred. You will know if you have had acute glaucoma because this condition causes episodes of severe eye pain.

Chronic glaucoma is the most common form of the condition. It usually occurs after the age of 35 years but is sometimes seen in children. The condition tends to run in families and is more common in certain racial groups, notably Afro-Caribbeans. The cause of chronic glaucoma usually is unclear. However, it may result from:

  • A previous eye injury or surgery, especially if this involved bleeding into the eye
  • A previous infection or inflammation
  • Blockage of a vein in the eye
  • A tumour
  • Steroid treatment

Acute glaucoma is usually due to the shape of your eyeball and is most common in 'long-sighted' people. When the pupil dilates, the drainage channel gets blocked. Consequently, an attack of acute glaucoma can be brought on by anything that causes the pupil to dilate: dim lighting, some eye drops or certain medications including some types of antidepressant medicine. Less commonly, the pressure in the eye may rise suddenly after a blow to the eye or during an attack of iritis (inflammation of the iris, the coloured part of the eye). Some people with diabetes may also suffer from a similar condition.

Glaucoma Screening
Open-angle glaucoma, the most common form of the disease, is often referred to as the "silent thief of sight" because there are no physical symptoms until vision loss occurs. As a result, it is important to have annual eye exams that include a glaucoma test to check intra-ocular pressure. In individuals with the greatest risk for glaucoma, the eye doctor should perform a comprehensive eye exam. This includes:

  • Family history
  • Visual acuity test
  • Intra-ocular pressure check - also known as tonometry
  • Drainage angle inspection - also known as gonioscopy
  • Retinal and optic nerve exam (this will require pupil dilation)
  • Evaluation of the visual field - also known as perimetry, this test evaluates how far peripheral vision extends

If the glaucoma is caught early, it can be managed before severe vision loss occurs.

Glaucoma Treatment
Glaucoma cannot be cured, but it can be treated in one of two ways: glaucoma medication or glaucoma surgery. Both of these treatments are aimed at lowering intra-ocular pressure. In the U.S., medications are considered to be the first-line treatment for the disease. If this fails, then surgery will be considered.

What are the Common Symptoms and Complications of Glaucoma?
If you have chronic glaucoma, there is a very gradual increase in pressure that slowly damages your optic nerve, resulting in a slow progressive loss of vision. Usually both eyes are affected. You may not notice the visual loss to begin with as it starts at the edges of the field of vision. However, if it is not treated, it can eventually cause blindness.

In someone with acute or 'closed-angle' glaucoma, symptoms start suddenly and usually affect only one eye. Initially, there may be a slight decrease in vision, the appearance of coloured halos around bright objects and pain in the eye and head. After a few hours the symptoms become much more severe with rapid loss of vision and sudden, severe throbbing pain in the eye. The eyelid swells and the eye becomes red and watery, with a dilated pupil that doesn't respond to light by closing, as it should. There may be nausea and vomiting. Although most symptoms disappear after treatment with medication, there may be some remaining loss of peripheral vision. Attacks can re-occur. If they do so, then each one tends to further reduce the field of vision.

How do Doctors Recognise Glaucoma?
Glaucoma is diagnosed by measuring the pressure of the fluid in the eyeball: the 'intra-ocular pressure'. This is usually done with a 'tonometer', of which there are two basic types. The simplest uses a puff of air blown against the surface of the eye. More commonly, a Goldman tonometer is used, as this gives more accurate measurements. To use this, the ophthalmologist (eye specialist) will put some drops in your eyes. These may sting slightly to start with but then the surface of the eye becomes numb. Using a microscope, the tonometer is then brought in close so that it lightly touches the surface of the eye. The procedure takes only a moment or two and is painless. During an attack of acute glaucoma, the diagnosis is usually easily made. However, in chronic glaucoma it is sometimes necessary to make a series of measurements over time to confirm the diagnosis.

There are some other tests that may be done. Firstly, the ophthalmologist will use an 'ophthalmoscope', an instrument with a bright light, to view the optic nerve at the back of your eye. Secondly, your visual fields may be examined. For this, you will be asked to keep looking straight ahead at a central point and to say when you see a spot of light appear at the side. Finally, the eye may be examined with a contact lens with a tiny mirror attached. Eye drops are used to numb the surface of the eye first. This examination may take five to 10 minutes.

What is the Treatment for Glaucoma?
Self-Care Action Plan
Regular eye tests are recommended if you are over 40 years old. The test for glaucoma must be performed by a trained person, either an ophthalmologist or a trained ophthalmic optician. The test for glaucoma may not be a part of the standard eye test given and should be requested. If you have been diagnosed as having glaucoma of any sort, it is most important that you use any medication that you are given by the ophthalmologist as directed. You will need to attend regular follow-up appointments and you must report any loss of vision that you notice. If you have had an episode of acute glaucoma, then you should be aware of the early symptoms and consult a doctor immediately should they re-occur.

Medicines
Medicated eye drops, by increasing drainage of aqueous fluid or reducing its production, can usually control chronic glaucoma. These pressure reducing drugs may include:

  • A 'beta-blocker' (e.g. betaxolol)
  • A 'miotic' (e.g. pilocarpine)
  • Adrenaline-related drugs (e.g. apraclonidine)
  • A 'carbonic anhydrase inhibitor' (which may be taken by mouth; e.g. acetazolamide)

In an attack of acute glaucoma, treatment by mouth either with a carbonic anhydrase inhibitor or with glycerine solution can abort the attack, if taken early enough. In a severe attack, an intravenous injection of a drug called mannitol may be necessary to bring the intra-ocular pressure down promptly. Beta-blocker and pilocarpine eye drops are also usually given. After an attack, treatment usually continues with eye drops and doses of a carbonic anhydrase inhibitor.

Surgery
In all forms of glaucoma, if the pressure cannot be controlled with medicines and eye drops, or if the side effects are unacceptable, the drainage from the front part of the eye can be increased surgically. This can be done either by using a laser to create a hole in the iris or by using microsurgery to cut out part of the iris. Usually both eyes are treated.

What is the Outcome of Glaucoma?
Most people with glaucoma respond well to treatment. Intra-ocular pressure can usually be controlled by the regular and sustained use of eye drops and medication, preventing any further loss of vision.

What Can I do to Minimise the Impact of the Glaucoma?

Stress and poor nutrition are the primary causes of glaucoma. Thus a good natural multi-vitamin and other supplementation can help prevent or slow down this disease.

Nutrient / Supplement
Importance ( 1 - 10 )
Helpful Notes
Vitamin A
10
Vitamin that is helpful for glaucoma as tears contain vitamin A. This vitamin is also very important for general eye health.
Carotenoids
10
Work with vitamin A and are needed for all eye problems.
Multi-vitamin and Mineral Supplement
10
Contains vitamin A, vitamin E, vitamin C, selenium and zinc, which all are helpful for glaucoma. It will also provide raw materials needed for good health and well being.
Essential fatty acids
10
Protect and aid in the repair of new cells and body tissues. Fatty acids are found in omega natural sources like fish oil, flax seed oil and borage seed oil.
Ginkgo biloba
9
Herb that can help slow vision loss.
Lecithin
9
Needed by the eyes and brain.
Pantothenic acid
9
Vitamin B5 helps with stress and is required by the adrenal glands.
Glutathione
9
Strong antioxidant which helps protect the eye lens.
Inositol
9
Important for both the eyes and the brain.
Calcium
9
You may need more if your tear ducts are swollen.
Magnesium
9
Mineral that works with calcium.
Bioflavinoids
9
Bioflavonoids are agents that promote the production of natural healing elements in the body. They work with vitamin C.
Red Clover
9
Herb that serves to detoxify and cleanse the blood.
Dandelion
9
Herb that works with red clover.
Vitamin C
9
High doses of the vitamin can be helpful.
Vitamin E
9
Antioxidant properties help to protect eyes, lens and eye tissue.
Zinc
9
This mineral is essential in activating vitamin A from the liver.
Selenium
8
Mineral that works with vitamin E.

Note that permanent vision damage can occur in as little as 3 to 5 days making treatment within the first 24 to 48 hours critical.

Glaucoma probably has many causes, but it is closely related to stress and nutritional problems, and is often related to other disorders such as diabetes and high blood pressure. Problems with collagen have been linked to glaucoma; collagen is a widely used protein in the human body. Poor collagen metabolism often appears related to all forms of eye diseases and disorders.

OTHER CHANGES TO MAKE

- drink steam distilled water

- avoid alcohol

- avoid saturated fats and fried foods

- eat high fibre diet (brown rice and millet are good)

- make sure to get vitamin A, C, and E

- reduced sugar, sweets, etc ...

- avoid caffeine, hydrogenated oils, fried foods, meat, soft drinks

- reduce dairy products in your diet

- avoid cigarette smoke and second hand smoke


Homeopathic Remedies:

Herbs: Proponents of homeopathic medicine believe that symptoms represent the body’s attack against disease, and that substances which induce the symptoms of a particular disease or diseases can help the body ward off illness.

Holistic Treatments: Holistic medicine is a system of health care designed to assist individuals in harmonizing mind, body, and spirit. Some of the more popular therapies include good nutrition, physical exercise, and self-regulation techniques including meditation, biofeedback and relaxation training. While holistic treatments can be part of a good physical regimen, there is no proof of their usefulness in glaucoma therapy.

Eating and Drinking: No conclusive studies prove a connection between specific foods and glaucoma, but it is reasonable to assume that what you eat and drink and your general health have an effect on the disease.Some studies have shown that significant caffeine intake over a short time can slightly elevate intraocular eye pressure (IOP) for one to three hours. However, other studies indicate that caffeine has no meaningful impact on IOP. To be safe, people with glaucoma are advised to limit their caffeine intake to moderate levels.Studies have also shown that as many as 80% of people with glaucoma who consume an entire quart of water over the course of twenty minutes experience elevated IOP, as compared to only 20% of people who don’t have glaucoma. Since many commercial diet programs stress the importance of drinking at least eight glasses of water each day, to be safe, people with glaucoma are encouraged to consume water in small amounts throughout the day.

Good Nutrition: The ideal way to ensure a proper supply of essential vitamins and minerals is by eating a balanced diet. If you are concerned about your own diet, you may want to consult with your doctor about taking a multivitamin or multimineral nutritional supplement.Some of the vitamins and minerals important to the eye include zinc and copper, antioxidant vitamins C, E, and A (as beta carotene), and selenium, an antioxidant mineral. While no disease in humans has been proven to arise as a result of vitamin E deficiency, vitamin E added to regular glaucoma medication improved visual fields in a majority of patients studied. Vitamin E has also shown promise in the treatment of premature retinopathy.

Bilberry: An extract of the European blueberry, bilberry is available through the mail and in some health food stores. It is most often advertised as an antioxidant eye health supplement that advocates claim can protect and strengthen the capillary walls of the eyes, and thus is especially effective in protecting against glaucoma, cataracts, and macular degeneration. There is some data indicating that bilberry may improve night vision and recovery time from glare, but there is no evidence that it is effective in the treatment or prevention of glaucoma.

Remember that the Food and Drug Administration (FDA) has not tested homeopathic remedies for safety or effectiveness. There is no guarantee that they contain consistent ingredients, or that dosage recommendations are accurate. It would be a serious mistake to use homeopathic remedies and dismiss valid therapies, delaying proven treatment for serious conditions.

Physical Exercise: There is some evidence suggesting that regular exercise can reduce eye pressure on its own, and can also have a positive impact on other glaucoma risk factors including diabetes and high blood pressure.In a recent study, people with glaucoma who exercised regularly for three months reduced their IOPs an average of 20%. These people rode stationary bikes 4 times per week for 40 minutes. Measurable improvements in eye pressure and physical conditioning were seen at the end of three months. These beneficial effects were maintained by continuing to exercise at least three times per week; lowered IOP was lost if exercise was stopped for more than two weeks.In an ongoing study, glaucoma patients who walked briskly 4 times per week for 40 minutes were able to lower their IOP enough to eliminate the need for beta blockers.

Final results are not available, but there is hope that glaucoma patients with extremely high IOP who maintain an exercise schedule and continue beta-blocker therapy could significantly reduce their IOP.Regular exercise may be a useful addition to the prevention of visual loss from glaucoma, but only your eye doctor can assess the effects of exercise on your eye pressure. Some forms of glaucoma (such as closed-angle) are not responsive to the effects of exercise, and other forms of glaucoma (for example, pigmentary glaucoma) may actually develop a temporary increase in IOP after vigorous exercise. And remember - exercise cannot replace medications or doctor visits!

Yoga and Recreational Body Inversion: The long-term effects of repeatedly assuming a head-down or inverted position on the optic nerve head (the nerve that carries visual images to the brain) have not been adequately demonstrated, but due to the potential for increased IOP, people with glaucoma should be careful about these kinds of exercises.Glaucoma patients should let their doctors know if yoga shoulder and headstands or any other recreational body inversion exercises that result in head-down or inverted postures over extended periods of time are part of their exercise routines.

Self-Regulation Techniques: The results of studies regarding changes in IOP following relaxation and biofeedback sessions have generated some optimism in controlling selected cases of open-angle glaucoma, but further research is needed.However, findings that reduced blood pressure and heart rate can be achieved with relaxation and biofeedback techniques show promise that non-medicinal and non-surgical techniques may be effective methods of treating and controlling open-angle glaucoma.

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