Macular Pigment Density Subject to Different Autofluorescence Patterns in Patients With Age–Related Maculopathy

Abstract

Abstract: : Purpose: In patients with age–related maculopathy (ARM) we measured macular pigment density (MPD) using a modified confocal scanning laser ophthalmoscope (HRA Heidelberg Engineering, Germany) and investigated the correlation between MPD and different fundus autofluorescence (AF) pattern. Methods: In addition to ophthalmologic standard examination we took AF images with a confocal scanning laser ophthalmoscope (HRA, Heidelberg Engineering) using a standard protocol. For MPD measurement AF images at two different wavelengths (488 nm and 514 nm) were taken with a modified HRA. MPD was evaluated within 0,5° around the center of the fovea and analysed in relation to different AF patterns. Classification into eight different AF patterns was done according to the "international fundus autofluorescence classification group" (IFAG). Results: 199 eyes of 199 patients (116 women, 83 men; mean age: 71 ± 8 Jahre) with funduscopic visible drusen were included in the study. Incidence rate of AF patterns was as follows: "minimal change" in 81 eyes, "patchy" in 35 eyes, "focal" in 33 eyes, "speckled" in 15 eyes, "reticular" in 13 eyes, "lace–like" in 12 eyes, "focal plaque–like" in 6 eyes, and "linear" in 4 eyes. Mean MPD was 0,345 ± 0,123 D.U. (density units). Lowest mean MPD was found for "focal plaque–like" pattern (0,255 ± 0,103 D.U.), "lace–like" pattern showed highest mean MPD (0,447 ± 0,123 D.U.). Statistical analysis (Kruskal–Wallis–test) showed differences between groups of AF pattern. MPD in eyes with "lace–like" AF pattern was significantly higher than in eyes with "speckled" and "minimal change" AF pattern (p<0,01 in Mann–Whitney–test). "Focal", "reticular", and "focal plaque–like" AF pattern showed a significantly lower MPD as well compared to MPD of "lace–like" AF pattern (p<0,05). Between all other groups of AF patterns no statistically significant differences regarding MPD were found. Conclusions: "Lace–like" AF pattern shows a significant higher MPD compared to most of the other AF patterns. Statistically significant differences between all other AF patterns could not be found. A possible predictive interpretation of our results concerning a progression of ARM has to be investigated in further studies.

Keywords: macular pigment • age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)