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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.

{ 4 comments… add one }
  • koka November 29, 2012, 5:32 pm

    I been exposed to toxic mold (aspergillius/penicillium, stachybutrys an other toxins, I was diagnosed with Meige Syndrom, some dystonia, movement disorder, essential tremors, fatigue, to name few that Dr.s could come up with. The facial twitching and eyes blinking are most annoying so I stay home most of the time, searching for a cure which I am not getting from Dr’s so far they find things that there is not known cause and no cure. They injeted me with botox for my facial twitching and blinking I stoppted that but not soon enough. I found Dr. Shoemaker’s VCS
    test, so now I stambaled on your website. I live in California. Do you do same VCS test also.
    With Great Gratitude and
    Thank you
    Koka Adamovich

  • Dr. Larsen November 30, 2012, 9:37 am

    Yes, it is the same VCS test that Dr. Shoemaker does. It’s a very good screening test, especially for biotoxic people.

  • Nate cocharn October 15, 2017, 11:43 am

    I have been in the Photographic business for over 43 years. During that time I have dealt with contrast on a daily basis. You either see it or you don’t.
    The VCS test is pure Quackery. Don’t waste your money!!!

  • Dr. Larsen October 15, 2017, 12:09 pm

    Interesting when we see people get better symptomatically and overall health, and their contrast test changes.

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