Romona’s friends worried she was developing dementia. When she met them on the street or in the supermarket, she rarely recognized them. When they spoke to her, she seemed surprised but then returned to perfectly normal vision.

Ramona, too, was worried — about her vision. She could see well enough to get through daily activities, but when she tried to concentrate on recognizing a face or reading a page, there always seemed to be a blur obstructing her view.

Ramona had age-related macular degeneration (AMD), a disease that gradually destroys a person’s central vision. The disorder rarely presents itself before age 50, but is the leading cause of vision loss among Americans age 60 and over.

The macula is the central part of the retina, a layer of light-sensitive tissue at the back of the eye that forms images and sends them to the brain. When cells in the macula deteriorate, the result is a gradual (and sometimes rapid) loss of central vision — needed for precise tasks such as reading, writing, driving and recognizing faces. Peripheral vision is not affected.

Ten percent of cases progress to wet macular degeneration, which involves the growth of abnormal blood vessels beneath the retina. This is believed to be the body’s misguided way of making sure the retina gets the oxygen and nutrients it needs. Instead, the process creates damaging scar tissue.

Laser photocoagulation can prevent or slow further damage to the macula, but it only works for some types of wet AMD.

Another procedure is photodynamic therapy, which combines use of a cold laser with a drug activated by the laser light to close off the abnormal blood vessels. This is less likely to damage rods and cones in the retina. The light-sensitizing medication remains in the body for several days, however, and patients must avoid the sun during that period.

The newest treatments for wet AMD focus on vascular endothelial growth factor (VEGF), a substance that promotes the growth of new blood vessels in tissues not getting adequate oxygen or nutrition. VEGF levels are high in eyes with wet macular degeneration; and medications that block VEGF production have been found effective in treating the disease.

The first anti-VEGF drug approved by the FDA for the treatment of macular degeneration was Macugen (pegaptanib). Blocking the activity of one type of VEGF, it has been found effective in stopping the formation of new blood vessels and reducing leakage from those already present.

Lucentis (ranibizumab), also FDA-approved, blocks all forms of VEGF. And studies have found some patients treated with Lucentis regained some vision they had lost.

Avastin (bevacizumab), an anti-VEGF drug similar to Lucentis, has been approved as a treatment for colorectal cancer and for one form of lung cancer. Although it hasn’t been approved specifically for macular degeneration, many doctors are prescribing it “off label.”

Small studies have found outcomes with Avastin similar to those with Lucentis and at a cost of $25 to $50 per injection compared to $2,500 per injection for Lucentis and $1,000 for Macugen. At this time, safety tests conducted for Avastin are not as extensive as those conducted for Lucentis and Macugen.

Investigative treatments now being studied include Kenalog (triamcinolone), a steroid that reduces inflammation and swelling, and rheophoresis, a procedure that removes blood from the body, filters it and then returns it. The goal is to remove substances that may contribute to poor blood flow in the retina.

While none of the above treatments amounts to a cure, they are capable of stabilizing and controlling vision loss, as long as the disease is detected early enough.

Early signs include the emergence of shadowy, blurry or distorted spots in central vision.

It is best to get regular eye examinations with an ophthalmologist.



Rupp is information and assistance case manager with Northern Oklahoma Development Authority Area Agency on Aging.