PALM CITY -- The symptoms hit Richard Giuffreda in his left eye hard and fast. Sight began to blur in November 2005, and by Christmas that year his peripheral vision and depth perception were deteriorating. "All of a sudden I couldn't read books or newspapers, and I was having trouble on the computer," the Palm City resident said.

Giuffreda said he was examined by Dr. William Davenport of the Stuart Eye Institute. Davenport determined that Giuffreda was suffering from macular edema caused by retinal vein occlusion. In layman's terms, a vein was blocked and leaking blood into the part of his left eye that senses light.

There are two types of retinal vein occlusion, the third-leading cause of blindness among eye patients over 60. The type afflicting Giuffreda can be slowed or stopped, but is considered to be incurable.

"Two things were frightening," the retired Broward County sheriff's deputy said of his diagnosis. "I would be down one eye, and there's no known treatment."

But soon there might be.

Giuffreda said Davenport referred him to Dr. Adrian Lavina of Retina Care Specialists in Stuart and Palm Beach Gardens. Lavina determined the 68-year-old patient was eligible for clinical trials of a new treatment, and Giuffreda volunteered.

The treatment, called Posurdex, was developed by Allergan Inc. of Irvine, Calif. It injects a tiny, elongated pellet containing a drug called dexamethasone into the patient's eye. The pellet is designed to dissolve after it releases its medicine.

"It's an old drug that has been previously shown to be safe in the eye," Lavina said. "But it's a new delivery system, a controlled release."

The injection is "an almost painless procedure" done in a doctor's office, Lavina said.

Like all clinical trials of this type, some patients are in a control group that gets a placebo instead of the drug -- in this case, a fake injection. But if vision does not improve after six months, control group patients are eligible for an injection of the real thing, Lavina said.

Giuffreda said he has no doubt the first and only injection was real and worked.

That was spring 2006 and Giuffreda said his vision has been "steady ever since."

He has been able to return to driving at night, a chore temporarily given to his wife.

Giuffreda said he didn't mind being a volunteer for treatment not yet approved by the U.S. Food and Drug Administration.

"Obviously, when you're in a situation where there's no other choice for you, you go ahead and do it," he said. "As far as I'm concerned, this was God's blessing."