What is Snellen equivalent?
The Snellen acuity = Test distance (feet)/Letter size read (Snellen equivalent). For example, if the patient could read the 160 line at 1 meter, a 5′ equivalent, their acuity would be recorded as 5/160. 5/160 is equal to a Snellen acuity of 20/640.
What is teller card?
Purpose: The Teller acuity card procedure provides a quantitative measure of grating acuity in infants and young children and has been used in clinical and laboratory settings. The purpose of this study is to address the influence of the individual testers in a clinical setting.
How do you perform a visual acuity test?
You will be asked to cover one eye with the palm of your hand, a piece of paper, or a small paddle while you read out loud the smallest line of letters you can see on the chart. Numbers, lines, or pictures are used for people who cannot read, especially children. If you are not sure of the letter, you may guess.
How visual acuity is measured?
The most common method to measure visual acuity is the Snellen eye chart. Like all eye charts, the Snellen chart tests a patient’s ability to resolve high-contrast letters and is satisfactory if their vision is good.
What is Teller acuity test?
What is the Teller acuity vision test? This test is an assessment of your child’s visual acuity (sharpness of vision). It is used with infants, toddlers and nonverbal children because it does not require a verbal response. Your child’s doctor will use the results to recommend treatment and follow-up testing.
What is Snellen acuity?
The visual acuity test is used to determine the smallest letters you can read on a standardized chart (Snellen chart) or a card held 20 feet (6 meters) away. Special charts are used when testing at distances shorter than 20 feet (6 meters). Some Snellen charts are actually video monitors showing letters or images.
How do you write down visual acuity?
Visual acuity is expressed as a fraction, such as 20/20. Having 20/20 vision means that your visual acuity at 20 feet away from an object is normal. If you have 20/40 vision, for example, that means you need to be 20 feet away to see an object that people can normally see from 40 feet away.
What is Teller acuity?