What is commonly called “glaucoma” is actually a family of diseases. The common feature of this disease family is progressive atrophy (degeneration) of the nerve of the eye (the optic nerve), which initially leads to loss of peripheral (side) vision. Total vision loss can occur later in the course of the disease.
In a healthy eye, a clear fluid called aqueous humor flows in and out of the anterior chamber in the front of the eye, nourishing surrounding tissue. The fluid exits the chamber through the drainage angle, where the cornea and the iris meet. It drains through spongy tissue called the trabecular meshwork before leaving the eye.
If the eye is unable to properly drain fluid, the pressure inside the eye (i.e., intraocular pressure) can rise. This gradually threatens the health of the optic nerve, which is a bundle of nerve fibers that transmit information from the eye to the brain.
There are several different types of glaucoma. In cases of open-angle glaucoma, which is the more common form of the disease, the drainage angle remains open, yet the eye is not able to drain fluid as well as it should. It is as if the drainage angle is similar to a clogged drain. Open-angle glaucoma progresses very slowly and painlessly. Sadly, this occurs with either no symptoms or very few in the early stages of the disease, and by the time patients notice a problem, significant vision loss may have already taken place.
In the rarer form of the disease, angle-closure glaucoma, the drainage angle becomes completely blocked. This can happen if the eye’s iris is too close to the drainage angle. When the drainage angle becomes blocked, intraocular pressure spikes very rapidly, causing noticeable symptoms. This is considered an emergency and requires immediate medical intervention to avoid blindness.
In the majority of cases, glaucoma is associated with higher intraocular pressures (pressure inside the eyeball), although sometimes glaucoma damage can occur with seemingly “normal” or even low eye pressures.
As mentioned, with cases of open-angle glaucoma, there are very few obvious visual symptoms at first. Gradually, blind spots can develop in peripheral, or side, vision. Usually open-angle glaucoma is left undetected until the damage is very severe. Increases in intraocular pressure can be detected during eye exams, which is why ophthalmologists encourage older adults at a higher risk of developing glaucoma to have regular exams.
On the other hand, angle-closure glaucoma develops quickly, causing symptoms that can include the following:
- Very blurry vision
- Severe eye pain
- Nausea and vomiting
- Rainbow-colored rings or halos around lights
Treatment and Management of Glaucoma
Practically speaking, efforts to treat glaucoma are focused on lowering intraocular pressure. This can be accomplished by reducing the amount of fluid the eye produces or increasing the amount of fluid that exits the eye.
In broad terms, the treatment types available are:
- The daily use of eyedrops to lower the amount of aqueous fluid the eye makes or help fluid drain through the drainage angle.
- Laser procedures, which involve using a laser to help aqueous drain from the eye.
- Laser trabeculoplasty improves the way the drainage angle works, helping fluid flow out of the eye properly.
- Laser iridotomy creates a tiny hole in the iris to help fluid flow through the drainage angle.
- Traditional surgical procedures create new openings through which aqueous fluid can leave the eye.
- Trabeculectomy involves the creation of a small flap in the white of the eye and a pocket in the conjunctiva; the fluid exits the eye through the flap and collects in the pocket.
- Minimally invasive glaucoma surgery [MIGS] is a relatively new and exciting area of glaucoma treatment involving the implantation of tiny devices to create new ways for fluid to drain from the eye.
- Viscocanalostomy reroutes aqueous fluid from the trabecular meshwork through a newly created channel.
At Access Eye we offer treatments within each category. When appropriate, we can combine two different treatment modalities, such as laser or traditional surgery with the use of medicated eyedrops, for the best results. In more advanced cases, we can utilize a number of referral resources.
Many of our patients have been coming to us for management of their glaucoma over decades and the wealth of practical experience we have developed in this arena has enabled us to dedicate a large portion of our practice to treating this disease. Vision lost to glaucoma is, for the most part, vision lost forever. This makes early diagnosis and treatment the key to management of this disease.
– Dr. Arash Mansouri