BILATERAL MACULAR DRUSEN IN AGE-RELATED MACULAR DEGENERATION - PROGNOSIS AND RISK-FACTORS

Background: In patients with unilateral visual loss related to age-rel ated macular disease, the risk of visual loss in the second eye is doc umented as being between 7% and 10% per year. The risk is uncertain in those with good vision with each eye and bilateral macular drusen. Me thods: In a prospective study, 126 patients with bilateral drusen were reviewed annually for up to 3 years. Serial fundus photographs and fl uorescein angiograms were analyzed independently by two readers in a m asked fashion using a standardized grading scheme, including size, num ber, density, and fluorescence angiographic behavior of drusen. Result s: New lesions occurred in one or both eyes of 17 (13.5%) of the 126 p atients. The cumulative incidence of exudative or nonexudative lesions was 8.55% at 1 year, at 2 years 16.37%, and 23.52% at 3 years for pat ients older than 65 years of age. Significant risk factors included th e degree of confluence of drusen within 1600 mu m of the center of the fovea (P = 0.023), focal hyperpigmentation (P = 0.004), slow choroida l filling (P = 0.023), and focal extrafoveal areas of atrophy of the r etinal pigment epithelium (P = 0.042). Conclusions: The results give a n estimate for the incidence of complicating lesions in patients with bilateral drusen and identify those features indicating higher than av erage risk of visual loss.