Study Confirms What Optometrists Have Known Forever
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Eye Chart "Exams" May Miss Vision Problems
"The tests detect nearsightedness accurately but not farsightedness or astigmatism, study shows"
Yes. I have been screaming this from the mountaintops for 10+ years now. A "school screening" (or DMV "eye test", etc) is not an "eye exam". Those distance-vision acuity tests pretty much only pick up nearsightedness. Children with *significant* visual deficits who are literally at risk for blindness from refractive amblyopia routinely "pass" a visual acuity school screen with flying colors. I don't know how many times I've told a parent their child needed immediate intervention with glasses & patching to treat amblyopia, only to have the parent reply "but she never failed the school eye exam!"
I had a child one time who "passed" the school screening despite a +7.00 refractive error and 15 prism diopter esotropia. The school nurse called me a week later asking "WHY DID YOU PRESCRIBE GLASSES THAT HE DOESN'T NEED!!?? HE READ 20/40!!!!" I replied with an explanation of accommodative esotropia, suppression & 100% chance of amblyopia if not corrected.
A school screen is not an eye exam, and "passing" a school screen unfortunately doesn't mean much.
.
Eye Chart "Exams" May Miss Vision Problems
"The tests detect nearsightedness accurately but not farsightedness or astigmatism, study shows"
Yes. I have been screaming this from the mountaintops for 10+ years now. A "school screening" (or DMV "eye test", etc) is not an "eye exam". Those distance-vision acuity tests pretty much only pick up nearsightedness. Children with *significant* visual deficits who are literally at risk for blindness from refractive amblyopia routinely "pass" a visual acuity school screen with flying colors. I don't know how many times I've told a parent their child needed immediate intervention with glasses & patching to treat amblyopia, only to have the parent reply "but she never failed the school eye exam!"
I had a child one time who "passed" the school screening despite a +7.00 refractive error and 15 prism diopter esotropia. The school nurse called me a week later asking "WHY DID YOU PRESCRIBE GLASSES THAT HE DOESN'T NEED!!?? HE READ 20/40!!!!" I replied with an explanation of accommodative esotropia, suppression & 100% chance of amblyopia if not corrected.
A school screen is not an eye exam, and "passing" a school screen unfortunately doesn't mean much.
more confirmation of same:
ReplyDeletehttp://www.allaboutvision.com/conditions/eye-news.htm#adoles
Vision Screenings With Just an Eye Chart Can Miss
Hyperopia and Astigmatism
LIDCOMBE, Australia, August 2010 — In a study of 2,353 adolescent students in Sydney, vision screenings using eye charts viewed at a distance were found to be reliable indicators of nearsightedness (myopia), but not of farsightedness (hyperopia) and astigmatism.
Hyperopia is a risk factor for crossed eyes (strabismus) and lazy eye (amblyopia), which can cause serious vision problems over time.
The study included data for year 7 students with an average age of 12.7 years at 21 secondary schools in Sydney. To detect the hyperopia and astigmatism, the researchers used cycloplegic autorefraction (lens assessment after special drops are used to paralyze the pupil) and keratometry.
In vision screenings that use only eye charts, "many children with clinically significant levels of hyperopia and astigmatism would not be referred for treatment," wrote the study authors in their report that appeared in the July issue of Archives of Ophthalmology.