Comprehensive Eye Exam

If you’ve had a vision screening recently, you might say, “My vision is fine! I don’t need a comprehensive eye exam.”

But a vision screening provides a limited perspective on the overall health of your eyes. It’s a bit like getting your blood pressure checked and not getting the rest of your annual physical. You’ll have useful information, but it’s not the whole picture.
 

What are the Limitations of a Vision Screening?

Vision screenings only test your ability to see clearly in the distance. This is called visual acuity and is just one factor in your overall vision. Others include color vision, peripheral vision, and depth perception. The screening also doesn’t evaluate how well the eyes focus up close or work together. Most importantly, it doesn’t give any information about the health of the eyes.
 

Vision screenings are conducted by individuals untrained in eye health.

Vision screenings are offered in many places – schools, health fairs, as part of a work physical or for a driver’s license. Even if your physician conducts the screening, he/she is a generalist and only has access to a certain amount of eye health training. Most individuals don’t have the tools or knowledge to give you a complete assessment of your vision or eye health.

Vision screenings use inadequate testing equipment.
In some cases, a vision screening is limited to an eye chart across the room. Even when conducted in a physician's office, they won’t have the extensive testing equipment of an eye doctor. They also won’t be aware of nuances such as room lighting and testing distances all of which are factors that can affect test results.
 

What are the Benefits of a Comprehensive Eye Exam?

Comprehensive eye exams evaluate all aspects of your vision and eye health.
The comprehensive eye exam looks at your eye externally and internally for any signs of eye disease, then tests your vision in a variety of ways.

• External Exam – This is an evaluation of the whites of your eyes, the iris, pupil, eyelids, and eyelashes.

• Internal Exam – This is an evaluation of the retina and optic nerve while your eyes are dilated.

• Visual Function and Eye Health – This includes testing depth perception, color vision, peripheral vision and response of the pupils to light, as well as an evaluation of eye focusing, eye teaming and eye movement abilities.

• Glaucoma Testing – This is a test of fluid pressure within your eyes to check for the possibility of glaucoma.

• Visual Acuity – Your doctor will test your vision with different lenses to determine if glasses or contact lenses can improve your vision.
   

Comprehensive eye exams look at your total health history.
Even though you visit a separate office for your eye health, that doesn’t mean your eyes shouldn’t be treated holistically. Your eye doctor will discuss your overall health and that of your immediate family, any medications you’re taking and whether you have high blood pressure or diabetes. They’ll also want to know if you smoke and how much sun exposure you get. All these factors help the eye doctor properly assess your eye health.

UNDERSTANDING THE DIFFERENCE BETWEEN VISION SCREENINGS AND VISION EXAMINATIONS

Vision Screenings -  See  ¥hat Your Child May be Missing:
Vision  screening programs are intended to help identify children with eye or vision problems that threaten sight or impair their ability to develop and learn normally. However, vision screenings are a limited process and cannot be used to diagnose an eye or vision problem, but rather to indicate a potential need for further evaluation.
 

• Many vision screenings test for visual acuity only. Even the most sophisticated vision screening tools; administered by the most highly trained screeners, miss one-third of children with eye or vision disorders, according to a study funded by the National Eye Institute. A child may be able to see letters 20 feet away but that does not tell whether his eyes are able to work together to read materials IZ inches away, or if there is an eye health problem or vision perception problem.
• There may be no set standards and criteria for passing a vision screening. Results can be determined arbitrarily.
• A vision screening can give a parent a false sense of security. When the report indicates that a  child sees 20/Z0,   parents often assume that no further testing is needed and fail to ever take the child tor a comprehensive eye examination.
• Most screening facilities lack equipment to screen young children.  Vision screening using traditional methods by non-eyecare professionals is extremely difficult for children less than 4 years of age.
• Amblyopia (poor eyesight in one eye. sometimes known as “lazy eye”) is often missed if the eyes are aligned. Children have been known to peek with the better-seeing eye and escape detection of amblyopia.
• According to a study published by the American Academy of Pediatrics, vision screenings were not attempted on more than 60 percent of the three-year-old children in pediatricians' offices. They found that in general, the younger the child. the less likely it was that vision screening was attempted. (An attempt was defined as 10 or more seconds spent trying to get the child to cooperate with vision screening.)
• Less than 50% of the children identified as needing professional eye and vision care ever receive that care, and of those who do, the average time between the screening and thé examination is 18 months.

Vision Examinations  - Mora Than Meets the  Eye:
Comprehensive eye and  vision examinations can only be conducted by an eye doctor with the specialized training needed  to maI‹e a definitive diagnosis .and prescribe treatment Often, specialized equipment and procedures, which are not available as part of a vision screening program, are needed to adequately evaluate a child's eyes and vision status.

Clearly, the prevalence of vision disorders present in pre-school age children and the limitations of vision screening programs support the need for and value of early detection through a comprehensive eye and vision examination by an eye doctor.

Below are essential elements of a comprehensive eye the examination used to ensure that learning is maximized through good vision.
 

• The refractive state of the visual system, such as nearsighted farsightedness, or astigmatism is determined.
• Visual acuity is measured so that the student can read, work on the computer and see the board.
• Focusing or accommodation is an important skill that is tested. The eyes must be able to focus on the object at which they are aimed and easily shift focus from one object to another. This allows the child to move attention from a book or paper to the chalkboard and back. Sustained focus affects the ability to read or write for longer periods of time.
• The optometrist evaluates visual alignment and ocular motility, which means the muscles aiming each eye converge so that both eyes are aimed at the same object, refining depth perception.
• Binocular fusion (eye teaming) skills are assessed. These skills are critical to coordinate and align the eyes precisely so the brain can fuse the pictures it receives from each eye into a single image to enable the child to work comfortably and efficiently for prolonged periods of time. Eye-tracking skills are tested to determine if the child can track across a page accurately and efficiently while reading, and can copy material quickly and easily from the chalkboard or another piece of paper.
• Testing of color vision prior to school age is conducted since a large part of the early educational process involves the use of color identification and discrimination.
• Ocular health is determined by examining the structures of the eye.
• Elements of visual perception, such as depth (3-D)  clues used to interpret and  understand visual information,  are important visual functions that are typically investigated during a comprehensive eye exam.