It is important to check and assess your eyes for common diseases as your eyes can serve as an indicator of your overall health.
Some types of screening tests:
- Tonometry –Is an important test used to evaluate the patient’s risk of glaucoma by measuring the fluid pressure inside the eyes
- Fundoscopy –This test checks inside the fundus of the eye and other structures to detect and evaluate symptoms of retinal detachment. It is usually done if you have high blood pressure, diabetes or other diseases that affect the blood vessels.
- AMD (Age Related Macular Degeneration) – Is a test to check the central vision for any macular degeneration resulting in a central vision loss
- Visual Acuity – Tests the smallest letters you can read in a standardised chart held at a distance of 20 feet away
Automated Refraction Test & Keratometer
While over 75% of the U.S. population between ages 25 and 64
Over 75% of the U.S. population between ages 25 and 64 needs some kind of vision correction for the refractive error.
The refractometer is essentially automatic and objective for measuring the power of the eyes. The device filter out all but infrared light from the measuring system and detect the end-point by means of an electronic focus detector.
After calibration of the instruments empirically, the measurement of the power of the eyes are closely correlate with the subjective clinical refraction.
Additionally the built-in Keratometer measures the curvature and angle of the cornea which is essential information before the patient undergoes refractive surgery like LASIK.
Light entering the eye consists of many different wavelengths. The light is absorbed by tiny cells at the back of the eye called cones.
There are three different types of cones in the normal eye to capture long wavelength (red) light, medium wavelength (green) light and short wavelength (blue) light. The signals from these cones are sent to the brain where they are perceived as colour.
Colour blindness is a common hereditary condition. Around one in 12 men and one in 200 women has some sort of problem with their colour vision.
Red/green colour blindness which affects men more often than women is passed from mother to son on the 23rd X-chromosome (sex chromosome)
Whereas blue colour blindness gene is carried on non-sex chromosome; therefore blue colour blindness affects men and women equally.
A person could have poor color vision and not know it. Quite often, people with red-green deficiency aren’t aware of their problem because they’ve learned to see the “right” color. For example, tree leaves are green, so they call the color they see green.
How to diagnose colour vision deficiency?
Color deficiency can be diagnosed through a comprehensive eye examination. The patient is shown a series of specially designed pictures composed of colored dots, called pseudoisochromatic plates (Ishihara charts). The patient is asked to look for numbers among the various colored dots.
Individuals with normal color vision see a number, while those with a deficiency do not see it. On some plates, a person with normal color vision sees one number, while a person with a deficiency sees a different number.