• Written By: Alma I. Murphy, MD
    Comprehensive Ophthalmology

    This retrospective, population-based study found that the 20-year probability and population incidence of blindness due to open-angle glaucoma (OAG) in at least one eye has decreased significantly.

    There are numerous possible reasons for this, including improvements in diagnostic testing, medication and surgical techniques. Unfortunately a significant proportion of patients, which the authors estimate at about 15 percent, still progress to monocular blindness despite these advances.

    The study included all residents of Olmsted County, Minn., diagnosed with OAG between Jan. 1, 1965, and Dec. 31, 2000. The authors reviewed all available medical records of every incident case of OAG through Dec. 31, 2009 to identify progression to blindness, which was defined as either visual acuity of 20/200 or less, or visual field constriction to 20 degrees or less.

    The cumulative probability of OAG-related blindness in at least one eye decreased from 25.8 percent for subjects diagnosed in 1965 to 1980 to 13.5 percent for those diagnosed in 1981 to 2000 (P = 0.01). The population incidence of blindness within 10 years, calculated using U.S. Census data, decreased from 8.7 per 100,000 in subjects diagnosed between 1965 and 1980 to 5.5 per 100,000 in subjects diagnosed between 1981 and 2000 (P = 0.02).