By Darcie Fisher, Tufts Medical Center Correspondent
For many, staying healthy means eating right, exercising regularly and getting plenty of rest. But we should also keep our vision in our sights.
“If you have never had any eye issues, you should have a comprehensive eye exam at age 40,” said Sarwat Salim, MD, FACS Director of the Glaucoma Service at Tufts Medical Center. “If you are at high risk – have diabetes, high blood pressure, or a family history of eye problems, you should see an ophthalmologist right away for an exam.”
What is glaucoma?
Eye diseases are common and most can go on for a long time without causing any symptoms, explained Dr. Salim explained. One of those diseases, glaucoma, is known as “the sneak thief of sight” because it results in progressive vision loss without any symptoms early on. Glaucoma affects more than three million Americans and is caused by elevated intraocular pressure which results from fluid accumulation in the eye due to inadequate flow and compromise in the natural drainage outflow system of the eye – and this often leads to optic nerve damage. The optic nerve is responsible for transmitting information from our eyes to the brain to form the images we see.
“Everyone is at risk for glaucoma with advancing age,” said Dr. Salim. “You are six times more likely to get glaucoma if you’re over the age of 60.”
Age is not the only risk factor. Glaucoma is the leading cause of irreversible blindness in African Americans. In fact, glaucoma is 6 to 8 times more common in African Americans than in Caucasians.
“Other risk factors include family history, severe myopia or nearsightedness and diseases such as hypertension and diabetes. Long term use of steroids can also increase intraocular pressure. Potential genetic links to glaucoma continue to be an active area of research, and as our understanding of underlying genetic mutations increase, improved testing and targeted treatments will follow,” explained Dr. Salim.
Of the three million people living with glaucoma in the US, about half of them may not even know they have the disease. Dr. Salim says the most common type of glaucoma in the United States is open-angle glaucoma and is usually painless with no symptoms since the increase in intraocular pressure happens gradually.
“On the other hand, acute attack of closed-angle glaucoma presents with sudden and severe eye pain,” said Dr. Salim. “These patients usually experience decreased vision, rainbow-like halos around lights, nausea or vomiting. Acute angle closure glaucoma is considered an ocular emergency and must be addressed immediately.”
The best way to diagnose glaucoma is by having a complete eye exam. Glaucoma screening is typically part of annual vision exams. Dr. Salim says a complete exam should include the following specific tests:
- Visual acuity test
- Tonometry (measures intraocular pressure)
- Gonioscopy (assesses if the drainage angle is open or closed)
- Slit Lamp examination (assesses the anterior segment of the eye)
- Optic nerve examination and imaging
- Visual field test (assesses the loss of peripheral or central vision)
When necessary, patients are referred to glaucoma specialists who are ophthalmologists with fellowship training in glaucoma.
Unfortunately, glaucoma cannot be prevented or cured, but it CAN be controlled to minimize further vision loss. The American Academy of Ophthalmology recommends a complete eye exam by the age of 40. However, if you are at risk for glaucoma depending on the aforementioned risk factors, then you should have a complete eye exam sooner than age 40. For individuals who are at risk for closed-angle glaucoma, a laser procedure can be done before you have an attack to prevent optic nerve damage and vision loss.
Treatment for glaucoma
The goal of glaucoma treatment is to reduce intraocular pressure, and the type of treatment depends on the kind of glaucoma you have. Open-angle glaucoma is traditionally treated with eye drops designed to either reduce the formation of aqueous humor in the eye or increase its outflow from the eye. If medical intervention fails, laser can be used to open the eye channels to allow the fluid to flow out. If both medical and laser therapy don’t work, incisional surgery is often performed.
“Glaucoma is a chronic disease,” explains Dr. Salim. “Ongoing surveillance and monitoring are necessary to ensure the best possible outcome.”
Acute angle-closure glaucoma can lead to blindness if left untreated for just a few days. This is why immediate medical attention is crucial. With this type of glaucoma, medical intervention to lower intraocular pressure followed by a laser procedure called iridotomy is used – this makes a small opening in the colored part of the eye (iris) which relieves the attack. To help prevent an attack in the other eye, iridotomy is performed in the healthy eye as well.
Dr. Salim says this is a very exciting time in her field. Newer medications have been introduced over the last two years which reduce pressure in the eye by increasing the outflow of fluid through the natural drainage system. This is different than several other classes of medications which work by reducing the production of fluid, but don’t affect the outflow system.
“Newer stents and devices have been introduced to increase the outflow of fluid from the eye,” said Dr. Salim. “These fall under the category of micro-invasive glaucoma surgery or MIGS. These are often inserted at the time of cataract surgery. Many elderly patients present with both concomitant cataract and glaucoma. The choice of MIGS or more involved incisional surgery depends on the severity of glaucoma.”
Remember that an annual eye exam is just as important as an annual physical examination in order to protect your eyesight. To schedule an appointment with our eye center, request an appointment online or call 617-636-4600.
Posted January 2020
The above content is provided for educational purposes by Floating Hospital for Children at Tufts Medical Center. It is free for educational use. For information about your own health, contact your physician.