Heterochromatic flicker photometry is a noninvasive diagnostic test to measure MPOD. The macular pigment is made up of zeaxanthin and lutein, and these carotenoids protect the retina and shield it from harm caused by damaging light waves known as short-wavelength, high-energy, visible blue light. Damage from blue light has been linked to the development of age-related eye health concerns, and the National Eye Institute (NEI) expects a 50% increase in these concerns in the US by 2020.
How It Works
MPOD measurement is most commonly performed in ophthalmology and optometry offices. With the best results achieved in a quiet, darkened room, the patient views a small circular stimulus that alternates between a blue light which is supposed to be absorbed and a green light that is not. The patient sees a flicker the moment the macular pigment is saturated by the blue light and presses a response button on the device. An MPOD measurement is generated depending on how long it takes the patients to see the flicker. The physician then interprets and explains the results to the patient.
Who Should Be Tested?
Patients at risk for developing of age-related eye health concerns are candidates for HFP, but it’s recommended to start testing patients over 21 to detect any eye health changes early. MPOD measurements are an objective tool for estimating this risk, and MPOD can improve with nutraceuticals and changes in the diet to include foods rich in lutein and zeaxanthin. Central measurement on one eye is typically the only measurement necessary to get an understanding of macular pigment health.
Long-Term MPOD Measurement
Measurement over time can assess whether dietary changes and/or supplementation with the macular carotenoids start to rebuild the macular pigment and diminish the harmful effect of blue light. Any changes, whether they indicate improvement or decline, provide clinicians with another data point to assess a patient’s risk level for developing eye health concerns. While this assessment emits blue light, it is not in large enough amounts to cause damage to patients’ eyes. Periodic testing in at-risk patients with high oxidative stress (smokers, heavy drinkers, and those with low fruit and vegetable intake) can help identify, evaluate, and manage early signs of age-related eye health concerns.