Correlation between the macular pigment optical density and macular function measured with objective perimetry in early age-related macular degeneration

Abstract

Purpose : To compare per-region sensitivities and delays obtained from macular objective perimetry with 2-dimensional (2D) macular pigment densities (MPOD) obtained at matching retinal locations in subjects with varying severities of age-related macular degeneration.

Methods : Objective perimetry used the ObjectiveField Analyser (OFA) and MPOD used a Heidelberg Spectralis OCT. Both were completed twice by 29 subjects (71.6 ± 6.25 y, 22 females). The pairs of visits were separated by 0.989 ± 0.162 y. The number eyes at AREDS-1 to -4 severities, were 26, 15, 10, 7. The OFA displayed 20 large stimuli to the central 18 deg of the visual field. Its 3-rings of stimuli scaled with eccentricity having areas of 6.87, 12.6 and 28.3 deg², centred on 1.75, 4.0, 6.0 deg eccentricity. The OFA stimuli and 2D MPOD signal extended to 9 deg eccentricity. Spectralis normally reports a 1-dimensional radial average MPOD. We used the raw fluorescence images to calculate 2D MPOD images. We then extracted 20 regions from the MPOD images that matched the sizes and shapes of the 20 OFA stimuli. For each of those MPOD regions we calculated 7 measures including the mean, median, and standard deviation. Those measures were correlated with the OFA corresponding per-region sensitivities and delays. Correlation significance was Bonferroni corrected for multiple comparisons.

Results : Sensitivities had the largest number of significant correlations being > 0.8 for the mean and median MPOD of the central ring in AREDS-4. AREDS-4 showed significant measures in all rings (r=0.4 p<0.001). Rings 1 and 2 had significant measures for AREDS-3. For delays, AREDS-2 and -3 showed the most significant relationships in ring 1, but these were related to MPOD variability (e.g. std, iqr). Modest but significant correlations (r>0.27, p<0.01) occurred in rings 2 and 3 for AREDS-4.

Conclusions : Overall, changes in MPOD tended to be most correlated with central changes but spread peripherally in later stages. This agrees with published OFA data in AMD and early diabetic eye damage [doi:10.1167/tvst.10.14.24 and 10.1167/tvst.10.13.32]. We are grateful to Kenneth R Sloan for assistance in calculating the 2D MPOD images.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

Correlations between MPOD and OFA sensitivities for the 3-rings (columns), and 4 AREDS severities (rows). White is r>0.8.