All About Eyes
Glaucomais the leading cause of blindness worldwide, especially for older people. But loss of sight from glaucoma is preventable if you get treatment early enough.
Glaucoma is the name given to a group of eye diseases in which the optic nerve at the back of the eye is destroyed; the optic nerve carries the images we see to the brain. Many people believe that glaucoma has something to do with pressure inside the eye. The higher the pressure inside the eye, the greater the chance of damage to the optic nerve.
The optic nerve is like an electric cable containing a huge number of wires. Glaucoma can damage nerve fibers, causing blind spots to develop. Often people don’t notice these blind areas until much of the optic nerve is destroyed and results in blindness. Early detection and treatment by your ophthalmologist is the key to preventing optic nerve damage and blindness from glaucoma.
What Causes Glaucoma?
Clear liquid, called the aqueous humor, flows in and out of the eye. This liquid is not part of the tears on the outer surface of the eye. You can think of the flow of aqueous fluid as a sink with the faucet turned on all the time. If the “drainpipe” gets clogged, water collects in the sink and pressure builds up. If the drainage area of the eye, called the “drainage angle” is blocked, the fluid pressure within the inner eye may increase, which damages the optic nerve.
What are the Different Types of Glaucoma?
Chronic Open-Angle Glaucoma, is the most common glaucoma. It occurs as a result of aging. The “drainpipe,” or drainage angle of the eye, becomes less efficient with time and pressure within the eye gradually increases. If this increased pressure results in optic nerve damage, it is known as “chronic open-angle glaucoma”. Over 90% of adult glaucoma patients have this type of glaucoma.
“Chronic Open-Angle” glaucoma can damage vision gradually and painlessly. This condition is generally silent and severe glaucoma damage to the optic nerve can occur without the person’s knowledge. This occurs more frequently in people of African and Asian ancestry.
Angle-Closure Glaucoma, sometimes the drainage angle of the eye may become completely blocked. It is as though a sheet of paper floating near a drain suddenly drops over the opening and blocks the flow out of the sink. In the eye, the iris acts like the sheet of paper closing off the drainage angle.
When eye pressure builds up rapidly, it is called acute “Acute Angle-Closure Glaucoma”.
The symptoms include:
- Blurred vision.
- Severe eye pain.
- Rainbow haloes around lights.
- Nausea and Vomiting.
If you have any of these symptoms, call your ophthalmologist immediately. Unless an ophthalmologist treats acute angle-closure glaucoma quickly, blindness can result.
How is Glaucoma Detected?
Regular eye examinations by your ophthalmologist are the best ways to detectglaucoma. AtSharif Eye Centerwe can detect and treat glaucoma.
During a Complete and Painless Examination,Dr. Sharifwill:
- Measure your intraocular pressure (Tonometry).
- Inspect the drainage angle of your eye (Gonioscopy).
- Evaluate any optic nerve damage (Ophthalmoscope).
- Test the visual field of each eye (Perimetry).
Some of these tests may not be necessary for every person. You may need to repeat these tests on a regular basis, to determine if glaucoma damage is increasing over time.
Who is at Risk for Glaucoma?
High pressure alone does not mean that you have glaucoma. Your eye care provider puts together many kinds of information to determine your risk for developing the disease.
The most important risk factors include:
- A family history of glaucoma.
- Past injuries to the eyes.
- A history of severe anemia or shock.
The eye doctor will weigh all of these factors before deciding whether you need treatment for glaucoma, or whether you should be monitored closely as a glaucoma candidate. This means your risk of developing glaucoma is higher than normal and you need to have regular examinations to detect the early signs of damage to the optic nerve.
It is important for each of us, from infants to senior citizens, to have our eyes checked regularly, because early detection and treatment of glaucoma is the only way to prevent vision impairment and blindness.
This means your risk of developing glaucoma is higher than normal and you need to have regular examinations to detect the early signs of damage to the optic nerve.
How is Glaucoma Treated?
As a rule, damage caused by glaucoma cannot be reversed. Eye drops, pills, laser and surgical operations are used to prevent or slow further damage from occurring. With any type of glaucoma, periodic examinations are very important to prevent vision loss, as glaucoma can worsen without you being aware of it. Your treatment may need to be changed over time.
Glaucoma is usually controlled with eye drops taken several times a day, sometimes in combination with pills. These medications decrease eye pressure, either by slowing the production of aqueous fluid within the eye or by improving the flow leaving the drainage angle.
For these medications to work, you must take them regularly and continuously. It is important to tell all your doctors about the eye medications you are using.
Glaucoma medications may cause side effects. You should notify your ophthalmologist immediately should you experience any side effects.
Some eye drops may cause :
- Stinging sensation.
- Red eyes.
- Blurred vision.
- Changes in pulse, heartbeat or breathing.
Pills sometimes cause :
- Tingling of fingers and toes.
- Loss of appetite.
- Bowel irregularities.
- Kidney stones.
- Anemia or easy bleeding.
Laser surgery treatments may be effective for different types of glaucoma. The laser is usually used in one of two ways. In open-angle glaucoma, the drain itself is treated .The laser is used to enlarge the drain (trabeculoplasty) to help control eye pressure. In angle-closure glaucoma, the laser creates a hole in the iris (iridotomy) to improve the flow of aqueous fluid to the drain.
When operative surgery is needed to control glaucoma, your ophthalmologist uses miniature instruments to create a new drainage channel for the aqueous fluid to leave the eye. The new channel helps to lower the pressure.
Though serious complications of modern glaucoma surgery are rare, they can occur, as with any surgery . Surgery is recommended only if your ophthalmologist feels that it is safer to operate than to allow optic nerve damage to continue.
What is your part in Treatment?
Treatment for glaucoma requires a “team” made up of both you and your doctor. Your ophthalmologist can prescribe treatment for glaucoma, but only you can make sure you take your eye drops or pills.
Never stop taking or change your medications without first consulting your ophthalmologist. Frequent eye examinations and tests are critical to monitor your eyes for any changes. Remember, it is your vision and you must do your part to maintain it.
Loss of Vision can be Prevented
Regular medical eye exams may help prevent unnecessary vision loss.
You should have an examination:
- Every 3 to 5 years – If you are age 39 and over.
- Every 1 to 2 years – If a family member has glaucoma.