PURPOSE. Increasing evidence indicates that the macular pigments (MP) prote
ct the central retina and may retard macular disease. For that reason, a pr
actical method for measuring MP that does not require elaborate optics and
can be applied to diverse populations by operators with a modest amount of
experience was developed and validated.
METHODS. A small tabletop device based on light-emitting diodes (LEDs) as t
he light source with electronic controls was constructed. Macular pigment a
-as measured with the tabletop device with a 1 degrees test stimulus at 460
nm using heterochromatic flicker photometry, and the results were compared
with measurements using a traditional three-channel Maxwellian view system
with a xenon-are source.
RESULTS. Macular pigment density of 30 subjects (age range, 16 - 60 years)
was measured with both stimulus systems. Macular pigment measured with the
LED tabletop device in free view was highly correlated with MP measured in
Maxwellian view (y = -0.03 + 1.06x, r = +0.95). The average absolute differ
ence between the two techniques was 0.04 (SD: 0.03). The new technique was
not significantly affected by variations in lens optical density, pupil siz
e, or small head movements.
CONCLUSIONS. Pspchophysical measurement of MP provides a unique opportunity
to make repeated noninvasive assessment of the concentration of a protecti
ve nutrient in the retina. The availability of this new device should make
this measurement technology accessible to a wide variety of investigators f
or application to diverse populations.