Vision Screener

Everything there is to know about vision screener

 A vision screener is a tool used to look for eye disorders and potential eye problems. The primary care providers often do optic screenings as part of a regular check-up. The machine is used to find but not to diagnose ophthalmic issues. If a problem appears on the tool, the provider refers the patient to an eye care specialist for diagnosis & treatment, and the specialist does more thorough eye testing. Many ocular disorders and problems get successfully treated with minor surgery, corrective lenses, or other therapies. The spot vision screener is often helpful to check any possible optic problems in young children. The most common eye problem in children is amblyopia. With it, the children have reduced or blurry eyesight in one eye, or strabismus, in which both eyes point at different directions. Both of these problems are easily treatable when discovered early.

History of vision screener 

In 1899 in Connecticut, the first state-supported school started an optic screening program. They used a Snellen Chart, but the results were weak due to the low standardization of examination conditions. A reading specialist Betts believed a large number of reading problems were due to functional eye disorders. In 1934, he devised a line of slides to examine eyeball acuity, stereopsis, and fusion. He incorporated these slides into the instrument of testing keystone ophthalmic telebinocular vision, the first commercial stereoscope. It was the first significant step in eyesight screening after the Snellen Chart. In 1939, the American Medical Association determined the tool unacceptable due to its high failure rate. A physician, Sloane, was the first person to expose the requirement for ocular examination. In 1938, he devised the first test with medical input. The purpose of the assessment was to find the presence of disturbed vision by fast, accurate methods and then have an ophthalmologist remove the reason for the disorder. TheAmerican Medical Association approved the Massachusetts Test in 1947. O Yasuna was the first person to analyze the exam. Optical companies started using vision screeners in 1955 and assimilated the three essential parts of the Massachusetts Test involving heterophoria, acuity, and hyperopia. 

Indications to use a vision screener 

Eye healthcare and eyesight testing, consistency, and accuracy are necessary for the practical examination, findings & recommendations. Every spot vision screener has these seven essential functions:

  • Acuity 

An acuity test is a visual examination that includes checking optic details by reading a chart of letters and numbers of various sizes from a distance to verify the accuracy of a patient's eyesight.

  • Ambler 

The Ambler grid chart test is best to find eyesight problems related to the damage of the central retinal part, the macula, or the optic nerve due to macular degeneration.

  • Refractive Errors 

The test determines whether the shape of the eye bends light correctly. It decides if a patient needs contact lenses or glasses and checks for general problems, like astigmatism and nearsightedness.

  • Depth Perception

It is also known as a 3D imaging test. Best to check binocular vision in a patient, and find out a possible lazy eye. 

  • Colors

A blind color test examines if a patient has a color deficiency or blindness. It finds the inability of a patient to differentiate between particular colors.

  • Contrast

A contrast sensitivity assessment checks the capability of a patient to see the light and dark contrast. It is best in the diagnosis of cataracts.

  • Complete sight field 

The eye exam helps find dysfunction in the peripheral and central sight, which can cause the development of conditions such as pituitary disease, glaucoma, stroke, brain tumors, and other neurological conditions.

  • Spot vision screener in detection of risk factors of amblyopia 

Amblyopia is the most common reason for the preventable optic loss in children, and the American Academy of Pediatrics recently recommended a tool as an alternative to traditional eyesight examination in children of 3-5 years. 

  • Finding Eyesight Problems 

The equipment can check the person's ability to follow an object with his or her eyes, how the person's pupils respond to bright light, and the blinking of an eye on showing a light. Eyesight examination also helps to find the following optic problems, that affect both adults and children:

Near-sightedness, also known as myopia, is a condition that blurs things that are far away.

Farsightedness makes close-up things look blurry, also called hyperopia.

Astigmatism is a condition that makes the whole eyesight blurred.

People should get examinations regularly. The American Academy of Pediatrics and the American Academy of Ophthalmology recommended the following eyeball examination schedule. Analysis of newborn babies to check any ocular infections or other disorders. The test is necessary during a regular visit of a baby in hospital till the age of six months to four years. Children above five years and adults should get an assessment of their eyes every year. An adult with optic symptoms and problems should consult an ocular care specialist for a comprehensive examination.

Complications of using vision screener 

Screening of the eyes helps discover some ophthalmic problems, but it can miss some severe issues. 

  • The spot vision screener is not reliable in the proper identification of people who need ophthalmic care. In some cases, screening inhibits the early diagnosis of sight problems, as it can generate a false sense of safety for individuals who clear the assessment but have a problem. There are low chances of these individuals receiving treatment for their optic problem, which could worsen as a result.
  • Many screenings are only for distant acuity. Whereas the capability to see distant objects does not represent how well the eyes can focus on close things or work together. Some assessments may also involve an exam of optic coordination and a positive lens test for farsightedness. Anyhow, these additional tests may also miss a lot of visual problems.
  • Volunteers or administrative personnel who have little training about assessment have less knowledge to assess testing results competently.
  • Even when done in the office of a primary care physician, the scope of visual examination may get limited because of the type of testing equipment. Factors such as maintenance of the assessment tool, room lighting, and testing distance can affect exam results.

How They Work 

The user should hold the tool approximately three feet from the subject while looking at the shining lights & sounds. The screen tells if the item is too close or too far. It shows a spinning circle on his or her face and displays a report of ocular alignment, pupillary diameter, and estimated binocular refraction. The data gets stored and remains available for printing. The spot vision screener interprets all measurements within a particular range or tells if there is a complete optic exam requirement. When the device cannot evaluate a subject, it shows pupils not found, or pupils too small or out of range.

Distance Eyes Test

The practitioners use a wall chart to exam the subjects. The chart has multiple rows of letters. The most prominent letters are on the top row while the smallest letters are on the bottom. The patient will stand or sit twenty feet away from the chart. The clinicians ask the patient to cover one eye and read the letters, a single row at a time. Each eye gets tested separately. For children too young to understand, the test uses a wall chart with the letter E in different positions. The clinician asks the child to point in the same direction as the E. Some charts use pictures or letter C, instead.

Close-up Test

The test uses a small card with a written text. The lines of the text get smaller going down the card. The subject holds the card about fourteen inches away from the face and reads aloud. Both eyes get tested at the same time. The exam is for people above 40, as close-up sight gets worse with age.

Color Blindness Test

The clinician gives a card with hidden symbols and colored numbers in a background of multicolored dots. If the subject quickly reads the numbers or symbols, he or she is not color blind.

Market Leaders 

  • Depisteo Screener 

Depisteo Screener is a leader in the medical screening instrument industry, and its screening device combines electronic, optical, and advanced technology to perform a wide range of tests in patients.

  • Welch Allyn Spot Vision Screener 

This is a portable gadget to help users quickly detect ocular issues in patients of all ages. The device assesses both eyes at the same time from a non-threatening distance of three-feet. The screen allows one-touch activation, data entry, and simple configuration for autorefraction applications.

  • Plusoptix eyes screening 

They use the measuring rules of a transillumination exam. In comparison to other transillumination tests, Plusoptix instruments avoid the patient's glare by using IR light. The pupils of the patient remain large even without dilation. The tool is to empower pediatricians, lions' clubs, head starts, and nurses to find the most common optic disorders as early as possible. 

  • VT1 Spot Vision Screener 

This vision screener is highly comprehensive equipment that contains all assessment tests relevant, and operators can customize it. It saves a lot of time & promotes efficiency. The device is compatible with the EMR software, and users can do driver acuity tests under 5 minutes–saving lots of time. It is a valuable tool for optometrists to conduct assessments like acuity with letters and symbols, color, horizontal and vertical phorias, and depth perception.

Conclusion 

The spot vision screener is a handheld portable device designed to efficiently detect optic issues on patients from 6 months of age to adults. The practitioners can use the tool for autorefraction and visual assessment. Usually, people get visual examination on the following symptoms: improperly aligned eyes, imbalanced eye contact, closing or covering one eye, squinting, trouble doing close-up work or reading, blurry sight, droopy eyelids, watery eyes, blinking more than usual, sensitivity to light and redness in one or both eyes. Hence, a spot vision screener is an essential instrument in the ophthalmology field of medicine.