Contrast Sensitivity and its clinical significance.

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What is contrast sensitivity?
Contrast sensitivity is the visual ability to see objects that do not stand out from their background. In other words, contrast sensitivity test measures the ability to distinguish between fine increments of light versus dark (contrast).
This is different from the familiar visual acuity testing in a standard eye exam, which measures the ability to recognize smaller letters on a standard eye chart . The ability to see a shade of grey on a white background or to see white on a light grey background declines with age. Cataracts, diabetic retinopathy and other conditions can also affect contrast sensitivity.

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A person with low contrast sensitivity may have such vision difficulties as:

• Difficulty seeing traffic lights at night
• Difficulty seeing spots on clothes, counters, or dishes
• Not getting facial gestures
• Difficulty seeing whether a flame is burning on a stove
• Requiring more light to read
• Eye get tired while watching television.

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Contrast Sensitivity Testing
Contrast sensitivity tests measure the degree to which the ability of Contrast detection has been lost. A contrast sensitivity test takes into account two variables, size and contrast. The ability to detect objects of different sizes at lower contrasts is known to be a higher contrast sensitivity function. This test determines an individual's threshold for contrast detection, the lowest point at which a pattern can be seen.

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Importance of contrast sensitivity test
Contrast sensitivity is a very important measure of visual health function, most especially when it comes to low light situations, fog or glare, when the contrast between objects and their background is very much reduced. Driving at night is an activity that requires good contrast sensitivity to ensure the safety of both the driver, the passenger and the pedestrian. Again, measurements are important in diabetics and patients with cataract. Cataract's clouding of the eye’s crystalline lens, causes light to scatter on the retina and thus reduce the image contras, causing the vision to dim. Many cataract patients have good visual acuity, but they still notice a loss of their visual capability. Contrast sensitivity testing can provide a true "real world" vision of a patient’s functional vision.

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What is @bettervision about?

@bettervision is is a project initiated by @nattybongo and friends to give back to the society the knowledge and skill acquired through the Optometric Studies in Kwame Nkrumah University of Science and Technology, Ghana.It is an outreach system where we visit the less privileged communities to offer free eye screening services and education to the people within the community

AIMS AND OBJECTIVES
To reduce or prevent vision loss through diseases such as glaucoma, cataract and refractive errors.

To enlighten the majority of the Ghanaian population about the importance of proper visual care.

To conscientize people on the need for regular eye checks

To get more people to have their wards screened within the Critical periods of a Child’s Vision Development; thus from ages 3 to till about 10 years.

To help the blind and people with low vision live a better life within the society through education of the general public to stop stigmatization.

We would so much be glad and grateful if you could support @bettervision with your Delegation by simply clicking any of the preferred links below. Many Thanks for your support.

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Our greatest gratitude goes to @fundition @adollaraday @surfyogi @girlsfoundation @bleepcoin @ackza @indigoocean @nanzo-scoop @steemstem @demotruk @pennsif @steem-ambassador @kasho and @wafrica for helping to make the aims and objectives of @bettervision a reality.

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