Measuring macular pigment optical density using reflective images of confocal scanning laser system.

Abstract

Purpose: To develop a method to measure the macular pigment optical density (MPOD) using scanning laser ophthalmoscopic images in young adults and children.

Study design: Cross-sectional study.

Methods: Blue light reflectance fundus images of 32 healthy subjects were used. A profile of the linear reflectance changes across the center of the fovea on a grayscale fundus image was generated. The ratio of the macula-to-periphery reflection was designated as the peak value of the MPOD (MPOD_[FR]) based on established fundamentals. In the MPOD profile, the basal width of the pixels at MPOD < 0 (wMP) and width at one-half value of the MPOD_[FR] (wMP_0.5) were determined. The MOPD at eccentricity of 0.5° was measured by heterochromatic flicker photometry (MPOD_[HFP]), and the correlation between the MPOD_[FR] and MPOD_[HFP] was evaluated.

Results: The MPOD_[FR] ranged from 0.17 to 0.73 with a mean of 0.40 ± 0.13. The wMP ranged from 88 to 173 pixels with a mean of 121.7 ± 24.2 pixels, and the wMP_0.5 ranged from 38 to 83 pixels with a mean of 54.1 ± 10.3 pixels. A significant correlation was found between the MPOD_[FR] and MPOD_[HFP] (r = 0.41, P = 0.02).

Conclusions: This simplified method can provide accurate and reliable values of the MPOD comparable to heterochromatic flicker photometry. Obtaining the fundus images in this fast and easy way should be suitable for children thus enabling clinicians to determine the MPODs for children.