New Tools Combat Eye Disease
By Virginia Smyth
A state-of-the-art scanner and drugs work together to improve vision.
Early last year, Betsy Potts noticed blurred vision in a portion of one of her eyes, so she made an appointment with her optometrist, Michael Hassur, OD, at Group Health Medical Centers downtown Tacoma location. The news was not good. He diagnosed retinal vein occlusion, a serious condition that causes swelling behind the eye.
She was referred to Group Health Physicians ophthalmologist Michael Brush, MD. Two recent developments gave Dr. Brush new tools to diagnose and treat Potts. As a result, she can see nearly as well as she did before her eye condition developed. Other patients with eye conditions that can result in permanent vision loss and even blindness are also seeing improvements to their vision as a result of these new tools.
A Clearer Picture for a Better Diagnosis
For many years, ophthalmologists relied on an angiogram to give them a picture of the retina, the light-sensitive membrane that covers the back of the eye. With an angiogram, a dye is injected into the patient's blood. When dye reaches the eye, photographs are taken that can reveal problems in the retina such as leaking blood vessels, swelling, tumors, or blockages.
But an angiogram is a crude instrument when compared with the images provided by the optical coherence tomography (OCT) scanner. With an OCT scan, doctors get a cross section, three-dimensional view of the retina. "The technology has developed quite quickly over the last five years," says Dr. Brush. "The OCT is faster than an angiogram and it provides better quality images." For patients, the scan is quick, painless, and doesn't require anything but shining a light into the eye.
Drugs That Restore Vision
Around the same time that the OCT scanner was being developed, doctors began using the drugs Avastin and Lucentis to treat a number of eye diseases, including:
- Diabetic retinopathy. This affects people with diabetes whose blood sugar is not under control. It damages blood vessels in the retina and, if untreated, can cause permanent vision damage and blindness.
- Age-related macular degeneration. Older adults are most at risk for this disease that leads to loss of central vision. Abnormal blood vessels under the retina can bleed and damage the cells that respond to light.
- Retinal vein occlusion. This blockage in the blood supply from the retina often — but not always — is caused by another condition, such as high blood pressure or diabetes.
In the past, lasers were used to treat some of these eye diseases. The goal was to prevent the condition from worsening. Today, these drugs can often restore vision loss caused by these eye disorders. "These drugs, combined with the OCT scan, have dramatically changed the way some eye conditions are treated," says Dr. Brush, who calls them "a dramatic leap forward."
The drugs are injected into the eye. "It's not as terrible as it sounds," says Potts. "Your eye is numbed. The shot is just a dull ache that lasts for a few seconds. "A bigger downside is that the effect of the drugs wears off after several weeks, and the injection must often be repeated. "Sometimes the body does heal itself and after a number of injections, no more are needed," Dr. Brush says.
For Potts, the small amount of discomfort associated with the shots is a minor inconvenience. "It's far better to have this treatment. Within three or four days of the injection, I can tangibly see that my vision has improved. Without the treatment, it would be hard for me to read and to have distance vision. My experience has been very good."