The Most Common Type of Glaucoma and its Treatment.
One of the most compelling reasons to see your optometrist for a comprehensive eye exam is to be evaluated for signs of glaucoma. Glaucoma is one of the leading causes of vision loss and blindness in the United States. Glaucoma has no noticeable symptoms – until it’s too late and vision loss has already occurred. Once vision loss occurs it can not be reversed. However, early detection and treatment can help prevent vision loss, and if vision loss has occurred there are treatments to prevent further loss of sight. Your optometrist will be able to evaluate and diagnose glaucoma with a comprehensive eye exam even if you have never experienced symptoms. In fact, most people do not know they have glaucoma when they receive the diagnosis.
WHAT IS GLAUCOMA?
Glaucoma is actually a set of conditions that lead to vision loss and blindness. The most common type of glaucoma is called open-angle glaucoma. Open-angle glaucoma is a condition in which the fluid (aqueous humor) in your eye that drains normally begins to drain slowly, which causes pressure to build in your eye. That pressure begins to slowly damage the optic nerve, which in turn causes vision loss.
This slow drainage is not painful, or even noticeable. It occurs in your eye, so you will not see the fluid leave your eye either. The drainage occurs in the open angle between the iris and cornea. The open angle itself does not become blocked, but the trabecular meshwork through which the fluid flows when it leaves the open angle can become blocked. This causes the fluid to flow at a rate that is too slow and leads to a build-up of fluid and pressure in your eye.
The biggest problem is that vision loss can be very gradual – so gradual that many people don’t even realize their vision is worsening until they have completely lost peripheral vision (with glaucoma your peripheral vision is lost first.)
There are two types of open-angle glaucoma, there is primary open-angle glaucoma and secondary open-angle glaucoma. Primary open-angle glaucoma has no known cause. It can happen to anyone even if they have none of the known risk factors for glaucoma. Secondary open-angle glaucoma has a variety of causes including eye injury, tumors, diabetes, heart disease, hypothyroidism, or use of corticosteroids. Other risk factors include a family history, age (especially those over 60), and ethnic background. Those of African-American or Mexican-American descent are much more likely to develop glaucoma and often do so at a younger age. It is important to schedule regular eye exams for glaucoma screening – even if you don’t have any of the risk factors mentioned.
Open-angle glaucoma is most often treated with medicated eye drops. It is important to use your eye drops exactly as directed. Often, because patients don’t experience symptoms, they forget to us their drops. It is important to use your drops or to take any medications as prescribed in order to prevent vision loss.
Surgery may be recommended for patients if drops and medications do not help prevent vision loss. Talk to your optometrist about surgical options as there are several to choose from if surgery is needed. Remember, vision loss caused by glaucoma is often preventable, and the sooner you are diagnosed and treated the more likely you are to keep your vision.
Next month we will cover other types of glaucoma, including juvenile glaucoma and normal tension glaucoma, and their risk factors and treatments.
For more information about glaucoma please see related articles:
To schedule a comprehensive eye exam and to find out more about glaucoma and its treatment please call Redding’s family-focused optometrist, Kristi Davis O.D., at 530-222-7271.