What is glaucoma?
Glaucoma is a group of diseases that damage the eye’s optic nerve. The optic nerve is like an electrical cable that contains about 1.2 million (nerve) fibers. Visual information is delivered to the brain by each eye’s optic nerve. Damage to these fibers causes sections of the eye’s field of vision to become more blurred. If undetected and untreated, the optic nerve can become significantly damaged, leading to an irreversible field of vision loss and blindness.
The primary treatment for glaucoma is to lower eye pressure. If the pressure is too high for the optic nerve, damage to the optic nerve fibers can occur. Our ophthalmologists use medical, surgical, and laser treatments to lower eye pressure. In some patients, treatment may not be necessary because the rate of damage is very slow.
Early detection and treatment can prevent vision loss and blindness from glaucoma. Annual dilated eye exams are recommended. Schedule an eye exam with Milauskas Eye institute to have our providers assess your eye health and recommend a monitoring or treatment plan.
How Common Is Glaucoma?
Worldwide, glaucoma is the leading cause of irreversible blindness. In fact, as many as 6 million individuals are blind in both eyes from this disease. In the United States alone, according to one estimate, over 3 million people have glaucoma. As many as half of the individuals with glaucoma, however, may not know that they have the disease. The reason they are unaware is that glaucoma initially causes no symptoms and the degree of visual field loss is hardly noticeable.
What Causes Glaucoma?
Glaucoma is usually caused by an increase of fluid pressure in the eye. The front part of the eye contains clear, nourishing fluid called aqueous which constantly circulates through the eye. Normally, this fluid leaves the eye through a drainage system and returns to the bloodstream.
Glaucoma can occur from an overproduction of fluid or when the drainage system becomes blocked, causing fluid pressure to increase. The high pressure causes damage to the optic nerve, resulting in permanent vision loss. The exact reason the fluid system in the eye stops functioning properly is not completely understood. However, research is constantly being done to further our understanding of glaucoma.
Am I At Risk Of Getting Glaucoma?
Knowing the risk factors for the disease and being screened for them will give you a head start on detecting and treating the disease. Doing so is important because any vision lost in glaucoma patients can not be regained. Glaucoma is a multifactorial disease and certain groups have a higher risk of developing glaucoma including:
- African-Americans – glaucoma is 6 to 8 times more common than in Caucasians
- Hispanic Americans in older age groups
- Eye injury patients
- All individuals who are over the age of 60
- Those with a family history of glaucoma
- Steroid users – frequent or prolonged steroid use can cause elevated eye pressure
- Elevated eye pressure
- Thinner corneal thickness
- Possible risk factors: people with diabetes and people with high myopia (severe near-sightedness)
What Are The Signs And Symptoms Of Glaucoma?
There are many types of glaucoma. Consequently, your best defense is to have regular eye exams and a glaucoma screening test, especially if you fall into a high-risk group.
Open-angle glaucoma – the most common type of glaucoma; The angle refers to the space between the cornea and the iris. In this space is the drainage structure of the eye, also called the trabecular meshwork. In open-angle glaucoma, this space is normal or “open”. There are no symptoms in open-angle glaucoma until the optic nerve becomes damaged and sections of your field of vision become blurred or opaque.
Acute angle-closure glaucoma– In this type of glaucoma, the space is closed or blocked and the nourishing fluid (aqueous) cannot leave the eye. This type of glaucoma is a medical emergency and if not treated immediately, blindness could occur in one to two days. Acute closed-angle glaucoma symptoms include:
- Severe pain
- Blurred vision
- Seeing a rainbow halo around lights
Chronic angle-closure glaucoma- In this type of glaucoma, the angle gradually becomes narrower over time. Like open-angle glaucoma, damage to the optic nerve can occur without any symptoms
How Is Glaucoma Treated?
The effects of glaucoma are permanent, but with early treatment, the loss of vision can be minimized. In some patients, damage occurs very slowly and treatment may not be necessary. Glaucoma can be treated with medications, laser surgery, traditional incisional surgery, or minimally invasive surgery.
Your doctor can help you decide which treatment plan is best for you. It is important to follow up at the recommended intervals to assess the stability of your glaucoma.
Glaucoma can be treated with:
Glaucoma medications come in the form of eye drops or pills. The medications need to be taken on a daily and regular schedule in order to work maximally. Generally, you will not know if the medication is working at lowering your eye pressure and so regular monitoring by your provider is important. While most medications are well tolerated, it is important to discuss with your provider potential side effects and interactions with other medications you are taking. To maximize uptake into the eye and minimize systemic absorption (i.e. uptake of the medication into your bloodstream), you can practice punctal occlusion with each eye drop. For example, after putting an eye drop in the right eye, press against the right side of your nose near the corner of your eye (this area is where the lacrimal sac is located) while keeping your eye closed for at least one minute.
For open-angle glaucoma, laser trabeculoplasty is becoming more commonly adopted as the initial step in the treatment of elevated eye pressure. There are two types- argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty. (SLT). Both are thought to increase the flow of aqueous (nourishing fluid) from the eye. This outpatient procedure takes 10-15 minutes and there is no sedation involved. After the procedure, the eye pressure is re-checked approximately one hour later. There are no activity restrictions postoperatively. It takes 6-8 weeks to determine whether the procedure has been effective so if you are taking glaucoma medications, it is important to continue them in the meantime.
For people with narrow angles (the space between iris and cornea is narrow), laser iridotomy is sometimes recommended. With the laser, a small opening is made in the iris to help open the angle. In this outpatient procedure, there is no sedation. Typically, anti-inflammatory eye drops are used for one week. There are no activity restrictions postoperatively. On the follow-up visit, the angle is re-evaluated with a test called gonioscopy. In some cases, iridoplasty laser procedure is used after laser iridotomy because the angle continues to be too narrow. This laser is used to “thin” the iris where it comes into contact with the trabecular meshwork (drainage structure of the eye).
For some patients with elevated eye pressure, transscleral cyclophotocoagulation (e.g. MicroPulse P3) is a possibility. In this procedure, the laser probe is applied to the surface of the eye. The laser treats the ciliary body (the ring of tissue in the eye that produces aqueous) so that less aqueous is produced.
Traditional incisional surgery
There are two types—glaucoma filtration surgery and glaucoma implant surgery. In glaucoma filtration surgery, aqueous fluid leaves the eye through a “trapdoor” in the wall of the eye, usually located under the upper eyelid. In glaucoma implant or shunt surgery, a small tube is inserted into the eye. The aqueous fluid leaves the eye and is collected in a reservoir created by a plate that is attached to the tube.
Minimally invasive surgery (MIGS)
This category encompasses a large group of exciting newer glaucoma procedures. They are not indicated for advanced glaucoma.