A Color Perimetric Test to Evaluate Macular Pigment Density in Age-Related Macular Degeneration

To evaluate differences in measurements of macular pigment optical density (MPOD) in patients with dry age-related macular degeneration (AMD) and a group of healthy patients (control group). Short-term repeatability of MPOD measures was also assessed in the control group.

This cross-sectional study included 31 eyes from 31 patients with bilateral dry AMD, 21 eyes from 21 cases with dry AMD in the study eye and exudative AMD in the fellow eye. The control group included 17 eyes from 17 healthy patients of similar age and sex. The MPOD values were measured using a commercially available color perimetry technique (CP). Short-term repeatability of MPOD measurements by the CP technique was assessed in 20 eyes of 20 healthy subjects who were measured 3 times on 3 consecutive days.

The mean values for MPOD were 5.59 ± 2.06 dB in cases in which both eyes had dry AMD, 5.25 ± 2.72 dB in cases in which one eye had wet AMD and the studied eye had dry AMD, and 5.97 ± 2.14 dB in the eyes of the healthy control group. The mean value was lower in cases in which the fellow eye had wet AMD; however, no significant difference in MPOD was found between the three groups (p = 0.659) or between the group with dry AMD in both eyes and the healthy control group (p = 0.977). The intraclass correlation coefficient (ICC) value was 0.664 between day 1 and day 2, and 0.822 between day 2 and day 3.

Our results do not show a direct relation between MPOD and dry AMD. Color perimetry does not provide acceptable short-term repeatability for measuring MPOD. Learning effects may contribute to the measured test-retest variability. Other studies are needed to determine if CP is suitable for repeated measurements during the long term follow-up with the same patient.