Glaucoma is a group of vision-threatening eye diseases that can cause damage to the nerve fibers within the optic nerve, that connect to the brain at the back of the eye. This progressive and irreversible damage to the optic nerve sadly makes this one of the leading causes of vision loss.
A healthy functioning eye produces a clear liquid called aqueous humor at an astounding rate of 1% per minute. At that rate, this nourishing fluid within the eye will completely turn over about every 100 minutes, bringing nutrients to the cornea and the lens.
Ideally, the eye’s natural drainage system will keep up with the flow of the aqueous humor, however, in patients with the disease, the fluid doesn’t exit the eye at a fast enough rate, resulting in heightened eye pressure.
The increased force from the additional fluid presses against the delicate nerve fibers at the back of the eye, killing off the irreplaceable nerves that are essential for healthy vision. These destroyed optic nerve fibers will often result in lost peripheral (side) vision.
Although there are several, the two main types are open-angle and angle-closure.
Open-angle is the most common and occurs in approximately 90% of those who suffer from the disease. In this particular type, the drainage channels in the angle (called the trabecular meshwork) are partially blocked, causing the aqueous humor liquid to drain out of the eye too slowly.
The exact cause of open-angle remains unknown, but it usually develops gradually and without any symptoms or red flags in the earlier stages. As a result, open-angle glaucoma can go undetected for years, leaving patients unaware that this disease is slowly stealing their vision. When and if symptoms do occur, patients with open-angle may notice:
- A gradual loss of peripheral vision, usually in both eyes
- Tunnel vision in the advanced stages
Angle-closure also referred to as “closed-angle” or “narrow-angle”, affects less than 10% of glaucoma patients and has a much more rapid onset. This occurs when the iris protrudes forward to narrow or block the drainage angle formed by the cornea and the iris.
As a result, aqueous fluid can no longer reach the trabecular meshwork at the angle, so the eye pressure spikes rapidly. Symptoms occur suddenly and are much more severe, but the good news is vision can be preserved with prompt, effective treatment. Angle-closure signs and symptoms include:
- Severe eye pain
- Nausea and vomiting (accompanying the severe eye pain)
- Sudden onset of visual disturbance, often in low light
- Sudden blurred vision
- Rainbow-colored rings or halos around lights
- Reddening of the eye
Sometimes, this eye disease can be traced to a known cause, such as an eye injury, inflammation, a tumor, diabetes or an advanced cataract.
According to the American Academy of Ophthalmology, patients who may be at greater risk for developing this eye disease include individuals who:
- are over age 40
- have family members with the disease
- are of African or Hispanic heritage
- have high eye pressure
- are farsighted or nearsighted
- have had an eye injury
- have corneas that are thin in the center
- have thinning of the optic nerve
- have diabetes, migraines, poor blood circulation or other health problems affecting the whole body
The key to preventing serious vision loss or blindness is early detection. An annual fully dilated eye examination is highly recommended and could uncover this disease before symptoms even occur.
Although vision loss can’t be recovered, we are fortunate to have plenty of treatment options available to help halt the progression of this disease and avoid further vision damage.
There’s a wide spectrum of treatment options available, depending on the type and stage of the patient’s disease. Eye medications are often the first method used in the treatment and are designed to either reduce the amount of aqueous humor being made within the eye or help this fluid flow better through the natural drainage system.
For patients who may need more drastic measures, laser procedures and even surgery may be better options. Each method has the ability to lower the internal eye pressure to a certain degree, and the surgeon will thoroughly discuss his or her recommended treatment plan with you.
We’ve been fortunate to have additional procedure options available to our patients over the recent years. The iStent has played a tremendous role in surgical management, but we’re happy to offer several other new treatment options as well.
Vision loss from this disease is permanent but can usually be prevented with early detection and treatment. Eye disease management is usually a lifelong process that requires frequent monitoring and constant treatment. Since there is no way to determine if the disease is under control based on how a person feels, patients with glaucoma generally should be examined every 3-6 months.
If you have experienced a loss of peripheral vision or are having other difficulties with your vision, schedule a complete eye examination with your primary eye doctor.
Can this be prevented?
No. However, if the disease is detected early enough, the damage to the eye can be stabilized.
Can this be treated?
Yes. With early detection and treatment, we can usually prevent serious vision loss or blindness.
How long does an evaluation take?
A full evaluation with a surgeon can be quite lengthy – often 2-3 hours. There are a variety of tests performed, some to determine your eye pressure, others to investigate if your vision has been damaged, and to what degree. These tests are painless and leave no after-effects.
Once the surgeon has reviewed the results, he or she will discuss the findings and recommended a treatment plan if one is needed. Any remaining questions or concerns you may have will also be addressed.
What are the treatment options?
The good news is there are a number of highly effective treatment options available for those suffering from glaucoma. Most individuals are started on eye drops as the initial treatment plan. Laser therapy may be appropriate for certain forms of the disease.
Finally, if medical or laser therapy fails to control the disease, a surgical procedure may be necessary. Fortunately, with early detection, most forms of the disease can be successfully treated and visual loss may be halted. The physicians and surgeons at Minnesota Eye Consultants have the latest in diagnostic technology, offering the earliest detection and most effective treatment options.