Related Experiment Video
Updated: May 24, 2026
Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer
Published on: January 29, 2020
Short- and mid-term repeatability of macular pigment optical density measurements using spectral fundus reflectance
Nikolaus Dragostinoff1, René Marcel Werkmeister, Semira Kaya
1Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
Background:
Several methods have been proposed for measuring macular pigment optical density (MPOD). To date, none of the realized techniques can be considered as "gold standard". A key issue for the clinical applicability of a method is its repeatability. In this study, we investigated short- and mid-term repeatability of MPOD measurements using reflectometry.
Methods:
A total of 12 healthy young subjects were measured 5 times on 5 consecutive days. Repeatability over 6 months was investigated in patients with AMD. The data in AMD patients were taken from a recently published placebo controlled study investigating the effect of lutein supplementation on MPOD (n = 37; [1]). Four measurements over 6 months were used to calculate repeatability. Spectral fundus reflectance of the fovea was measured in a 2.3° detection field with a custom-built fundus reflectometer. Calculation of MPOD was based on a previously published fundus reflectance model.
Results:
The coefficients of variation were 6.2 ± 2.4% and 8.0 ± 5.5% in the healthy and AMD group, respectively. Bland-Altman plots indicate that the difference between measurements at day 1 and day 5 in healthy subjects and day 1 and month 6 in AMD patients was small. The maximum deviation in MPOD in a healthy subject was 0.07 (22.6%), and 0.17 (51.5%) in a patient with AMD.
Conclusions:
Reflectometry provides adequate short-term and mid-term repeatability for measuring MPOD. Accordingly, the technique makes it possible to monitor MPOD in patients with AMD and to study the influence of supplementation in these subjects. In addition, the variability of the technique is small enough to allow for clinical trials with reasonable sample size.
Insights
Reflectometry shows good repeatability for measuring macular pigment optical density (MPOD). This technique is suitable for monitoring MPOD in patients with AMD and for clinical trials.
Area of Science:
- Ophthalmology
- Biomedical Optics
- Retinal Imaging
Background:
- Macular pigment optical density (MPOD) measurement methods lack a gold standard.
- Repeatability is crucial for clinical applicability of MPOD measurement techniques.
- This study evaluates the short- and mid-term repeatability of MPOD measurements using reflectometry.
Purpose of the Study:
- To assess the short-term (5 days) and mid-term (6 months) repeatability of macular pigment optical density (MPOD) measurements.
- To determine the suitability of reflectometry for monitoring MPOD in patients with age-related macular degeneration (AMD).
- To evaluate the potential of reflectometry for use in clinical trials investigating MPOD.
Main Methods:
- 12 healthy subjects were measured 5 times over 5 days.
- Repeatability over 6 months was assessed in 37 AMD patients using data from a previous lutein supplementation study.
- Spectral fundus reflectance was measured using a custom fundus reflectometer, with MPOD calculated via a published reflectance model.
Main Results:
- Coefficients of variation were 6.2 ± 2.4% (healthy) and 8.0 ± 5.5% (AMD patients).
- Bland-Altman plots showed small differences between measurements over the tested periods.
- Maximum MPOD deviations were 22.6% (healthy) and 51.5% (AMD patients).
Conclusions:
- Reflectometry demonstrates adequate short- and mid-term repeatability for MPOD measurement.
- The technique is viable for monitoring MPOD in AMD patients and assessing supplementation effects.
- The method's low variability supports its use in clinical trials with practical sample sizes.
