Macular drusen are one of the earliest signs of age-related macular degeneration but little information is available on the functional aspects of macular area in patients with drusen. To determine if drusen are associated with changes in central visual field sensitivity, one eye of each of 35 subjects (mean age 64.9 years) with bilateral drusen and visual acuity of 1.0 (20/20) underwent automated static threshold perimetry of the central 10 degrees. 16 normal subjects (mean age 65.8 years) were used as controls. 30 degrees fundus photographs were graded in a masked fashion for the clinical characteristics of drusen: type, size and number. The mean sensitivity (MS) of the central 10 degrees was significantly lower in eyes with drusen compared to normal eyes (p = .0001). After grading drusen eyes for size (> or = 63 mu) and type (presence of soft drusen), MS significantly deteriorated when large and soft drusen were present. These results suggest that central visual field sensitivity is precociously affected in eyes with drusen and that testing central visual field sensitivity may be useful as functional parameter in long term studies on the evolution of age-related macular degeneration.