What causes glaucoma?
It is estimated that approximately 10 to 33% of those with open-angle glaucoma have inherited certain types of mutations in their genes from their parents. In particular, a gene called the MYOC gene, which gives instructions for the production of myocilin, a type of protein that is found in parts of the eye. When mutations occur, there can be excess protein formation, which stops the free-flowing movement of fluid to and from the eye. This is because the body continues to produce fluid to keep the eyes hydrated, but it cannot properly drain from the eye. In a healthy eye, fluid should leave the eye through what is called a trabecular meshwork, which can be viewed as a small pipeline for the fluid to exit. When fluid does not drain so freely, this causes a lot of pressure within the eye and leads to damage to the optic nerve. This damage is often irreversible, as the optic nerve has been robbed of nutrients and oxygen over a lengthy period of time. For this reason, early intervention is crucial.
Warning signs of glaucoma
Unfortunately, there are no warning signs or symptoms with this predominant form of glaucoma. Because this type of glaucoma develops slowly over time, those that suffer from it don’t usually notice a loss of vision until the disease is quite developed. Open-angle glaucoma can progress over many years without any noticeable symptoms. The typical characteristics of open-angle glaucoma are the gradual loss of peripheral (side vision) before that loss of vision moves more centrally and becomes noticeable. It is not usually until central vision loss occurs when its sufferers realize something is not right. Sadly, by this point, most of the damage has been done. The best approach to avoid becoming a victim of open-angle glaucoma is to have regular eye examinations. If you have a family history of glaucoma, high or low blood pressure or diabetes, it is highly recommended to undertake regular eye examinations.
Unlike open-angle glaucoma, angle-closure glaucoma commonly comes with a sudden attack and a series of symptoms due to the increase in pressure behind the eye. Some of the symptoms include:
- Blurred vision
- Severe pain behind the eye region
- Sudden loss of sight
- Pupils are different sizes
- Vomiting and nausea
- Strong headaches
- Seeing halos of light
Angle-closure glaucoma is a common cause of irreversible blindness.
Risk groups of glaucoma
Age seems to be a huge risk factor, as open-angle glaucoma is rare in Americans under the age of 50, yet it affects 8% of those over the age of 80. In particular, certain ethnicities are more at risk of developing glaucoma, including:
- African Americans & Hispanics –The most common form of glaucoma, open angle glaucoma, is five times more common in African Americans and Mexican Americans, than that in Caucasians. In African Americans, it is noted that glaucoma often develops at an earlier age than Caucasians, and is likely to progress a lot faster.
- Asian ethnicities –From various studies, it has been found that Asia accounts for 77% of angle closure glaucoma.