Contrast Sensitivity

Contrast Sensitivity and Eye Health

Contrast sensitivity is a very accurate and sensitive measure of eye health. A contrast sensitivity test can measure improvements in vision after treatment with Lumega-Z. Improvements in contrast sensitivity can occur as early as 2 to 3 months after patients start taking Lumega-Z. The Big E chart, typically used by eye care professionals to test your vision, cannot measure these improvements until many months later, if at all.

Below is an example of the Big E Chart, formally known as The Snellen Chart. The chart tests only black-on-white letters.

While the Big E Chart measures only black on white, contrast sensitivity measures how well you can see shades of gray in the real world. Below are two pictures of the same real-world scene, one in high contrast and one in low contrast. Many people can read the black on white letters of the Big E Chart but have trouble seeing the little girl in the street under low contrast.

Contrast Sensitivity and Carotenoids

The secret to Lumega-Z’s ability to improve contrast sensitivity lies in its special and unique formula. Lumega-Z is the only Medical Food that contains all three macular carotenoids, as well as a full complement of antioxidant and anti-inflammatory ingredients. Further, Lumega-Z is the only Medical Food designed directly to replenish and restore the macular pigment, the area in the center part of your eye responsible for protecting and enhancing your central vision. Research shows that patients with reduced macular pigment often have reduced contrast sensitivity. After taking Lumega-Z, many patients report that they can see better in the real world under low-contrast conditions like driving at night, finding items in a darkened garage or stepping over a curb at dusk.

How Do You Measure Contrast Sensitivity?

The most scientific and accurate way to measure contrast sensitivity is to use a type of bar pattern, called a sine-wave grating, in a test that uses a calibrated light source which holds testing light level extremely consistent. During the test, different size gratings are presented to the patient at different levels of contrast. The patient simply says when they can or cannot see the gratings.

Some eye doctors use lower quality types of contrast tests that present gray letters instead of the scientifically proven grating bar patterns. These letter tests are less sensitive, and the FDA does not recommend letter contrast tests for use in their clinical trials.

Results for Study Comparing Lumega-Z to PreserVision

A study found significant improvements in visual function as measured by contrast sensitivity for patients taking Lumega-Z. Patients taking AREDS-2 showed no improvements in vision.

This graph shows the percent changes in contrast sensitivity, as measured by the CSV-1000, at baseline and after 3 and 6 months of treatment, for the control group (no treatment), the PreserVision Group and the Lumega-Z Group. Lumega-Z provided highly significant improvements in contrast sensitivity.

This graph shows the percent changes in contrast sensitivity, as measured by the CSV-1000, at baseline and after 3 and 6 months, for the control group (no supplementation), the PreserVision Group and the Lumega-Z Group. Lumega-Z provided for highly significant improvements in contrast sensitivity.

Individual Contrast Sensitivity Results Following Lumega-Z Treatment

The graph below shows the clinical data for a 70-year-old white female. The “Before” curve represents the patient’s contrast sensitivity before and the “After” curve shows the patient’s response after 6 months of taking Lumega-Z. Note that the patient shifted up dramatically in contrast sensitivity across the full range of the curve, at all spatial frequencies. The patient had 20/20 acuity before and after 6 months of treatment, which means that standard acuity testing could not have detected this difference. It is encouraging to find patients showing dramatic improvements in their vision after taking Lumega-Z (these results cannot be guaranteed for all patients).

You Should Have Your Contrast Sensitivity Tested Regularly

Contrast sensitivity is a very important measure of vision. You should have it tested regularly. In the United States, this test is not covered by insurance, although it is in many other countries. Make sure you ask for a test that uses the special scientifically proven gratings, as shown in the examples above, and one that ensures the test is conducted under conditions where the test lighting is standardized to the level recommended by the FDA and National Academy of Sciences.