Insights from Optical Express including latest news, treatments and key information.
The technical term for a freckle, spot or mole in or on the eye is a naevus, but the name makes the freckle sound more daunting than it actually is. Typically flat, round and grey in colour, these spots are often detected during routine eye tests and are usually not harmful. Though they are not normally present, they are still fairly common.
The term 20/20 (or 6/6) vision comes from the fact that the eye test chart is intended to be placed at a standard distance away from the patient being measured for visual acuity – 20 feet in the United States, and 6 metres in Europe. The numerator refers to the distance at which the person being tested can perceive the detail, whereas the denominator refers to the distance at which a person with normal visual acuity can perceive the detail. Thus, 20/20 vision means that you can see the same detail 20 feet away as a normal person. 20/40 vision, by contrast, indicates that you can see detail at 20 feet that a normal person can perceive from 40 feet away.
Dry eye, also known as keratoconjunctivitis sicca (KCS), is an eye condition often resulting from decreased tear production or increased tear evaporation.
The eye chart most commonly associated with eye tests – with a large Eat the top followed by progressively smaller rows of letters, is called the Snellen Eye Chart. Named after Dutch ophthalmologist Herman Snellen, who developed the chart in 1862, it is used to this day by optometrists to measure visual acuity.
Regardless of whether you’re crying or your eyes are watering, the liquid in your eyes is created in the same way. These tears help protect your eyes, keeping them moist and washing out dust and anything else that might get in there.