Function And Intended Application; Vision Disorders And Amblyopia - Welch Allyn SureSight Manual

Function and Intended Application

Thank you for purchasing the Welch Allyn SureSight™ Vision Screener. Please
read and follow the instructions found in this manual before using your new Vision
Screener to ensure accurate and reliable service.

Vision Disorders and Amblyopia

Amblyopia (lazy eye) is the leading cause of monocular blindness in North
America for those under 70. However, if risk factors are detected by age 4, 95%
of patients can have their vision saved and avoid the lifelong effects of amblyopia,
which may include a dramatically higher chance of loss of sight in the other eye,
learning delays, and limitation of career choices.
Two-thirds of children with amblyopic risk factors have refractive error (when the
eye's optics fail to clearly focus images on the retina). These include
anisometropia (unequal optical power of the two eyes), myopia and hyperopia
(near- and far-sightedness), and astigmatism (asymmetry of focus). Furthermore,
20% of teenagers suffer from a refractive error that requires corrective lenses
that can affect educational development when untreated.
The American Academy of Pediatrics, Family Practice, Ophthalmology, and
Optometry all advocate pre-school vision screening, especially a key check of
children aged 3 to 4. The latest research also indicates that it is a good idea to
check refraction in infants - and to begin treatment by age one. Early detection
reduces treatment time and expense and improves outcomes.
Traditionally, pediatricians and family physicians use visual acuity (eye) charts to
screen for refractive vision problems. Unfortunately, acuity testing of pre-
schoolers suffers from low compliance, poor specificity (false positives), and poor
sensitivity (false negatives).
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