World Glaucoma Week

Jabu Buthelezi, a 45-year-old member of the Government Employees Medical Scheme (GEMS), decided he should have his eyes tested, as his vision sometimes seemed a little blurry while he was driving at night. When Jabu finally found the time to visit an optometrist, the healthcare practitioner did a routine test for glaucoma, a fairly common eye disease that can cause blindness. It was most fortunate that the optometrist did the test because he found that Jabu did indeed have glaucoma and could refer him to a specialist for treatment.

Glaucoma is a group of eye conditions that cause damage to the optic nerve of the eye. Every year glaucoma causes large numbers of people to go blind. In fact, after cataracts, glaucoma is the second most common cause of blindness in South Africa. According to the South African Glaucoma Society (SAGS), 90% of affected people in developing countries and 50% in the developed world are not aware that they have the condition.

A lack of symptoms
Jabu was shocked to learn that he had glaucoma especially after he read on the internet that the condition can sometimes cause people to go blind. What is more, other than occasionally having a little trouble seeing clearly at night, Jabu had no warning whatsoever that he had such a serious ailment. Had he not gone to have his eyes tested, he would never have known that he had developed glaucoma.

Jabu's eye specialist, or ophthalmologist, said that he had open angle glaucoma, the most common form of the condition. Usually this kind of glaucoma does not cause any symptoms until the later stages of the disease. In many cases, the individual's eyesight has already been irreparably damaged before he or she is even aware of the condition. It is for this reason that glaucoma is often known as ‘the thief of sight'.

Glaucoma can be treated
Jabu's doctor reassured him that, while it is not curable, open angle glaucoma is treatable especially if it is detected early, as it was in his case. Treatment can minimise or prevent damage to the optic nerve and halt or reduce vision loss. Jabu's doctor said this is why it is so important for people to visit their optician or ophthalmologist regularly and have their eyes examined for glaucoma.

A build up of pressure
There are a number of different types of glaucoma but, as noted above, the most common form is open angle glaucoma. The eye contains a fluid called aqueous humor which is drained by a large number of small vessels. If this fluid is slowed or blocked in its passage through the eye it causes pressure to build. This is called intraocular pressure and if it is allowed to continue to build up unchecked, it can cause damage to parts of the optic nerve and may even cause a complete loss of vision within the space of just a few years.

What causes it?
It is not known what causes open angle glaucoma although it does often run in families. You should therefore be particularly vigilant if you have had parents, grandparents or siblings who have suffered from the condition.

There is also no known way to prevent glaucoma. As already noted, there are also generally no symptoms associated with open angle glaucoma although poor vision in dim light and blurred vision may be signs that you are developing the condition. Some individuals are certainly more at risk of developing glaucoma than others and they should be extra cautious.

Who is at risk?
Jabu's eye specialist told him that glaucoma is more commonly found in people over the age of 60, but it does sometimes occur in younger individuals such as himself and it even occasionally occurs in teenagers and children.

The following may increase the risks of developing glaucoma:

• Elevated internal eye or intraocular pressure - If your intraocular pressure is higher than normal you have a greater risk of developing the condition. Intraocular pressure tends to increase with age.
• Age - Those who are older than the age of 60 are at risk.
• Family history - Individuals who have had family members with glaucoma develop the condition more often than those who have not.
• Medical conditions - Those with conditions, such as diabetes, high blood pressure, heart disease and migraine are at greater risk.
• Ethnicity can play an important role with larger numbers of people of African descent developing open angle glaucoma.
• Other eye conditions may cause intraocular pressure including eye injuries and tumours. Being near- or far-sighted may also increase the risk.
• Long-term use of corticosteroids (which are commonly used in asthma treatment).

Detecting the condition
Regular eye testing is the only real way to detect glaucoma. It is therefore advisable for you to have your eyes tested at an optometrist or doctor every five years or so and even more often if you are over the age of 40. Before you go for your screening, make sure your eye care practitioner is able to undertake a glaucoma screening in addition to being able to perform the usual vision tests.

• Those who are over the age of 40 should be tested once every two years while individuals who are over the age of 60 should be tested annually.
• Those with a family member who have had glaucoma should be tested annually. This is especially important in a case where the family member was younger than 40 years of age when they developed the disease.
• Individuals of African descent who have had a family member with glaucoma should ask their eye-care practitioner how regularly they should be tested.

Individuals who suffer from diseases such as high blood pressure and diabetes must be sure to regularly visit their doctor who will assist them in controlling these conditions. If they remain uncontrolled these diseases can do a great deal of damage to the eye and contribute to the development of glaucoma.

Treatment
A few years ago glaucoma was sure to result in the loss of eyesight. Today there are a range of medications and procedures available, and the symptoms of the condition can be effectively treated, preventing the loss of vision. The goal of treatment is to stop further damage to the optic nerve from occurring, which is usually achieved using eye drops or other medications. Surgery is also occasionally used in certain cases.

Stick with it
It is important to note that the treatments for open angled glaucoma are designed to stop pressure building up in the eye. If the glaucoma sufferer stops his or her medication the pressure will build up very quickly once more and could cause damage to the ocular nerve and blindness. For this reason, it is critical that patients should never stop using their eye drops or taking their medication. Most people do not experience severe side effects from the treatment. However, if you have any problems with your treatment you should discuss these with your doctor.

Taking control
Jabu was diagnosed with glaucoma in October 2012 and has experienced no vision or other problems since then. "My eye care specialist has been very pleased with my progress," says a smiling Jabu. "However, I have been careful to follow his instructions and take my eye drops everyday. I am hopeful that if I continue to do this I can preserve my vision for many years to come."

"GEMS has been there at my side with me every step of the way through this challenge in my life," continues Jabu. "They have always efficiently handled my care and made sure I get my medication well ahead of time every time. I have been a proud member of GEMS for five years now and will never change," he concludes.

Sources
Mayo Clinic:  http://www.mayoclinic.com/health/glaucoma/DS00283/DSECTION=risk-factors
PubMedHealth:  http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002587/
WebMD:  http://www.webmd.com/eye-health/glaucoma-eyes
South African Glaucoma Society:  http://www.sags.co.za/faqs