Tent photoscreening and patched HOTV visual acuity by school nurses: validation of the ASD-ABCD protocol. (Anchorage School District- Alaska Blind Child Discovery program).

Background: Novel objective tests of risk factors for amblyopia offer an alternative for preschool vision screening. We compared the merits of photoscreening versus portable patched acuity testing in elementary schools. Photoscreening may outperform routine acuity testing in pediatric offices; however, both have fairly good validity when performed by specialists in preschool vision screening.

A comparison of patched HOTV visual acuity and photoscreening.

Early detection of significant vision problems in children is a high priority for pediatricians and school nurses. Routine vision screening is a necessary part of that detection and has traditionally involved acuity charts. However, photoscreening in which "red eye" is elicited to show whether each eye is focusing may outperform routine acuity testing in pediatric offices and schools.

Amblyopia detection by camera: Gateway to portable, inexpensive vision screening (calibration and validation of inexpensive, pocket-sized photoscreeners).

Background: Photoscreening can allow early detection of amblyopia. The Gateway DV-S20, and similar models of miniature, digital flash cameras, have similar optical dimensions to existing photoscreeners for less than $200.

Methods: These cameras were calibrated on known, threshold amblyogenic refractive errors induced by placing minus and toric contact lenses on a normal subject's left eye.