• PERFECT VISUAL ACUITY AND GOING BLIND

    Posted June 19, 2017: by Bill Sardi

    Catastrophic Level Of Visual Decline Looms As Commonly Used Vision Test Chart Fails To Detect Progressive Visual Deterioration

    Eye researchers have just now discovered that the commonly used vision testing chart does not adequately detect deterioration of the visual system in the early stages of eye disease while a more sensitive test that measures the ability of the eyes to adapt to the dark now points to a looming epidemic of preventable legal blindness.

    An age-related eye disorder called macular degeneration is responsible for a majority of the cases of legal blindness in the American population. About 30% of senior Americans show early signs of the disease (cholesterol-like deposits at the back of the eyes called drusen).  But a far smaller number, ~9%, have actually lost visual acuity to this eye malady.  These figures are anticipated to rise dramatically as more and more Americans are living into their tenth decade of life.

    In this scenario self-driving cars would be needed just to transport millions of Americans who can’t visually qualify for a driver’s license.

    But more alarmingly, a newly FDA-approved vision test suggests an epidemic increase in visual decline.

    According to a recently published study, while visual acuity as measured by the ability to read various size letters on an eye chart remains stable, senior Americans may be progressing towards legal blindness without knowing it.

    The dark adaptation test

    A more sensitive test that measures the ability of the eyes to adapt to the dark after exposure to bright light (Adapt Dx, Maculogix) can detect early and intermediate stages of eye aging.  When that dark adaptation test is used, a much higher rate of impending legal blindness is predicted.

    To explain dark adaptation, bright light bleaches chemicals needed for night vision from the retina at the back of the eyes.  When you walk from a bright sunlit outdoor environment into a dark room, your vision will be fuzzy until those chemicals refill.  The time it takes for those visual chemicals to refill and sharp vision to return is called dark adaptation time.

    If it takes more than 6.5 minutes for those chemicals to refill at the back of the eyes, this is indicative a future diagnosis of macular degeneration.  [Investigative Ophthalmology March 10, 2014]  The dark adaptation test can predict macular degeneration up to 3 years before any other evidence of the disease detected. [Ophthalmology Feb 2016]

    Just how many adults flunked the dark adaptation test?  Answer: a lot more than the often-quoted nine percent.

    A Kansas eye doctor reports 38 out of 90 patients (42%) could not adequately adapt to the dark (unpublished report).  Failure to adapt to the dark within 6.5 minutes is predictive of future onset of macular degeneration, a dreaded eye condition for which there is no proven treatment.

    The recently published study conducted among Americans age 70 years and over showed the time it took to adapt from bright to dark lighted conditions increased by six minutes or more among 36.7% of tested subjects over a 2-year period of time.  [Translational Vision Science & Technology June 5, 2017]  There was no parallel decline in visual acuity as measured by use of a standard vision-testing chart.

    In another published study of over 380 adults with nearly perfect 20/20 vision, 60-89 years of age, found 78% had normal dark adaptation time and 22% required prolonged time to adapt to dark conditions. [Investigative Ophthalmology & Visual Sciences May 2014]

    These figures point to a two to four times greater rise in the prevalence of macular degeneration than is currently predicted.

    The reported incidence of macular degeneration is 0% at age 50 years, 2.5% at age 70 and 6% at age 80.  [JAMA Ophthalmology April 2004] Typical age of diagnosis is in the mid 60s (65.8 years mean age).  By age 75 years about 30% of senior adults exhibit some degree of macular degeneration. [Survey Ophthalmology 2006]

    There are 1.75 million senior Americans that already know they have the disease but another 7 million seniors exhibit early signs (drusen deposits) at the back of the eyes and are at high risk for irreversible vision loss.

    According to an authoritative report, by the year 2020 an estimated 2.95 million Americans will have macular degeneration.   [Archives Ophthalmology 2004]  According to the Bright Focus Foundation there are currently ~11 million Americans with some form of macular degeneration. [Bright Focus Foundation]

    There are ~48 million Americans over the age of 65 and if the above figures translate to the entire population (22% of ~50 million), dark adaptation testing could uncover ~11 million senior Americans with near-perfect visual acuity who will develop macular degeneration in their near future.  Using 40% prevalence data, double that to 22 million!

    Is there any way to remedy this?

    Early detection and measurement of the progression of visual decline with advancing age is one thing, cooking up a way to put a halt to it is another.

    The currently recommended dietary supplement (AREDS formula) formulated by the National Eye Institute for macular degeneration doesn’t appear to have any influence in preventing or slowing this disease as measured by the dark adaptation test.  [Retina April 27, 2017]

    The only hope for therapy or prevention comes from a pilot study that showed a nutraceutical (Longevinex®) reversed the progression of retinal aging as measured by the dark adaptation test.  [British Journal Medicine & Medical Research June, 2017; 8 NEWSNOW KLAS-TV/CBS Affiliate, June 15, 2017J

    Given that 45% of adult offspring of patients diagnosed with macular degeneration, this appears to be the primary target group for prevention.  ####

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