Abstract
Purpose: :
To evaluate if retinal sensitivity values obtained with a dedicated screening device can be used to screen an early and intermediate age-related macular degeneration (ARMD).
Methods: :
A fully automatic fundus-perimeter combined with an image-stabilized scanning laser ophthalmoscope, Macular Integrity Assessment (MAIA, CenterVue, spa; Padova, Italy) was used in 355 ARMD patients. The standard automatic sensitivity grid (10 x 10 degrees, 61 stimulated points, centered on the fovea) was performed in 5 study sites. Fixation was simultaneously documented. Inclusion criteria were: age >50 years and AREDS 2 and 3 severity scale. Two hundred sixty five normal subjects were used as age-matched control group. Sensitivity point values (S-values), mean retinal sensitivity, number of points below 24 dB (K-value, considered as cut-off for normal values) and fixation stability were recorded. ANOVA, trend analysis, and summary statistics were calculated using Sigmaplot 11 (Systat Software, Inc; San Jose, CA).
Results: :
Of 355 patients, 200 were classified as AREDS 2 and 155 as AREDS 3. S-values and summary statistics between normals and ARMD were significantly different (ANOVA; p<0.001). Mean retinal sensitivity was significantly reduced in AREDS 2 and 3 vs normals (24.85dB+3.87 and 21.76dB+5.36 vs 29.78dB+1.71, p<0.001). K-value were different between AREDS 2 and 3 (ANOVA; p<0.001). Fixation stability did not differ between AREDS 2 and 3. S-values decreased toward the periphery of the examined area and varied by meridian.
Conclusions: :
Macular sensitivity is reduced in patients with early and intermediate ARMD when compared to age-matched normals. Sensitivity reduction is more relevant in intermediate than in early ARMD. These changes can be detected with a new screening device.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: systems/equipment/techniques • perimetry