Purpose:
The aim of our study was to evaluate and to compare macular pigment optical density (MPOD) of healthy young subjects measured with two
Methods:
the modified Heidelberg Retina Angiograph (HRA) versus the Zeiss Visucam 200.Methods: In this prospective study, healthy young subjects with no vitamin supplement were included, one eye per patient. We excluded subjects with any ocular or systemic disease. Maximal and mean MPOD (density units [DU]) were measured with both methods on the same day after recording demographics, vision and lifestyle details. The modified HRA used two-wavelength (488 and 514 nm) fundus autofluorescence (AF). The Zeiss Visucam 200 measured the reflectance of a single 460 nm wavelength.
Results:
Sixty-seven healthy young subjects were included, median age 25 (20 to 45). The modified HRA values were significantly higher than the Visucam values for MPOD at 0.5 and 2 degrees eccentricity around the fovea for modified HRA versus maximal and mean MPOD by Visucam, p < 0.0001. The mean MPOD by HRA at 0.5 and 2 degrees eccentricity around the fovea were respectively 0.49 ± 0.20 DU and 0.33 ± 0.13 DU. The maximal and mean MPOD by Visucam were 0.34 ± 0.06 DU and 0.12 ± 0.02 DU, respectively. The correlation coefficient between the two methods was low for maximal and mean MPOD, r² = 0.106, p = 0.007 and r² = 0.148, p = 0.001, respectively. With Bland-Altman analysis the mean differences (95% limits of agreement) were 0.15 DU (-0.22 to 0.52) for maximal MPOD and 0.21 DU (-0.03 to 0.45) for mean MPOD.
Conclusions:
Our findings showed that the agreement between modified HRA AF and reflectance by Visucam was moderate in measurements of MPOD. These results suggest that the two methods are not interchangeable.
Keywords: macular pigment • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: systems/equipment/techniques