Purpose: To determine the effect of drusen and geographic atrophy (GA) in dry age-related macular degeneration on retinal sensitivity using an eye tracking scanning laser ophthalmoscope microperimetry.
Methods: A total of 44 eyes from 22 patients with dry age-related macular degeneration and drusen and 11 patients with GA were imaged with scanning laser ophthalmoscope microperimetry (OPKO Health, Miami, FL). A custom microperimetry pattern was used to evaluate retinal sensitivity to a Goldmann III size target (108 μm on the retina). The perimetry used a 4-2 stepladder algorithm to determine maximal sensitivity. Microperimetry and optical coherence tomography were performed using a standardized protocol. Twenty-eight eyes with drusen and 16 eyes with GA were analyzed.
Results: Retinal sensitivity overlying drusen was significantly reduced compared with the adjacent uninvolved retina. There was a significant correlation between retinal sensitivity and drusen volume, as well as the grading of the photoreceptor inner segment/outer segment junction score. In patients with GA, an absolute scotoma was confirmed. Retinal sensitivity at the margin of GA was significantly decreased compared with the adjacent uninvolved retina.
Conclusion: Scanning laser ophthalmoscope microperimetry is able to detect changes in retinal sensitivity in AMD patients overlying drusen and at the margin of GA. It is a useful device to grade focal retinal sensitivity in patients with dry age-related macular degeneration.