Visual Contrast Sensitivity Test – Toxicity Testing

With the increasing rise of toxicity, and the increasing awareness of this huge problem, we need to have ways of determining which patients are likely to be severely toxic.

One way is with a proper history by a trained doctor. Personally, I use what is called a Neurotoxic Questionnaire. This, along with asking the right questions helps me determine what kind of toxicity a person may have (mercury, lead, biotoxins, etc.).

Another test that I use everyday is called a Visual Contrast Sensitivity (VCS) test.

This test is so accurate that if somebody fails the VCS test, there is less than 1% chance of a false-positive. This means that if a person fails the test….

they are probably sick.

Some people have such great visual acuity (about 8%) that they can pass the test, even though they are toxic.

How does the test work?

The Visual Contrast Sensitivity (VCS) test is a CONTRAST test, not an acuity test.

The ability to detect contrast is part of the brain’s function. Contrast is your ability to discern black from white, and also between different shades of gray.

Toxins affect nerves, and one nerve we can measure is the optic nerve. Toxins decrease  oxygen to the nerves by attaching to the fat and the nerve itself. This reduces blood flow to the nerves, effectively decreasing oxygen.

What will be lost is the ability to see contrast.

In later stages, it can cause blurred vision and other functional problems.

In our experience, biotoxic (mold, Lyme) patients will fail the VCS with greater severity than somebody with heavy metal toxicity (mercury, lead, etc.).

Also to note, this does not determine a diagnosis. A complete history and evaluation must be performed. The VCS is just one of the tests that we do.