retinoscopeLast week I brought a group of 1st year optometry students to an elementary school in Brooklyn .  We performed a vision screening on roughly 80 pre-kindergarten, kindergarten and 1st grade students.  I really enjoy taking 1st year students on vision screenings.  It’s their first real clinical experiences.  They get to practice what they have been taught on patients other than their classmates.  There are so many “teachable moments.”  It never takes more than 5 minutes before one of them notices something worthy of a referral for a comprehensive vision examination.  They begin to see the connections between various measurements and visual function in a classroom (and beyond!).  And who can resist smiling when you watch a 5 year old try to take apart a student’s  ophthalmoscope.

The purpose of a vision screening is to identify children with vision problems requiring intervention.  Sometimes these vision problems are easily overlooked.  A classic example is hyperopia (farsightedness).

When children are farsighted, they are able to compensate for the hyperopia by focusing their eyes.  They have to focus even more when reading or performing other near vision tasks.  The greater the hyperopia, the greater the focusing effort.  All that focusing can cause eye fatigue, intermittent blur, headaches, and inefficiency when using the eyes to gather information.  But it also allows the young hyperope to avoid blurry vision.  These children will pass the vision screening unless you search for the hyperopes.  That is one of the tests that we perform during a vision screening.  We include a certain procedure to look specifically for hyperopes with good visual acuity.

But a little bit of hyperopia is expected in children…….. so when do you refer?  How much hyperopia warrants a comprehensive eye exam and the possibility of an eyeglass prescription?

When discussing referring or prescribing for uncorrected hyperopia, I often point to an article written by Dr. Jerome Rosner in 1997:  The relationship between moderate hyperopia and academic achievement.  Rosner looked at the correlations between refractive error and performance on reading tests in a group of 782 elementary school children.  He found that the children with uncorrected hyperopia greater than +1.25 diopters were more likely to have lower reading scores.

Dr. Rosner drew a line in the sand — for children with hyperopia greater than +1.25, a comprehensive vision examination is indicated to determine if that child would benefit from lenses.  That was the number we used at the vision screening.  We referred many children for a variety of reasons;  that included several children who were able to read the letters on the chart 10 feet away, despite uncorrected hyperopia of greater than +1.25.

But identifying these children is only the first step in the battle against learning related vision problems.  These children need comprehensive vision examinations.  Hopefully that will happen and these children will be well on their way to successful performance in and out of the classroom.

Read more about vision screenings here and here.