Monday, August 1, 2011

Infant, Toddler & Preschool Vision Testing - Part 2

Children typically do not receive a comprehensive vision exam before entering school.  The brief pediatrician exam does NOT count.  It is estimated (Indiana University) that only 14% of children under age 6 are likely to have a comprehensive vision exam and only 31% of kids between 6 and 16 are likely to have an exam.

A recent retrospective study of comprehensive pediatric eye examinations reported the following as the most common disorders in children between 6 months and 18 years:
  • Farsightedness (hyperopia - eyestrain at near): 24.8%
  • Astigmatism (eyestrain at distance & near):  22.5%
  • Nearsightedness (myopia - distance blur):  18.2%
  • Subtle binocular disorders (ie: convergence insufficiency):  14.3%
  • Overt binocular disorders (ie: strabismus - crossed eye):  12.1%
  • Lazy eye (amblyopia - reduced sight in one eye):  7.1%
Photoscreening a young patient
Due to these problems it is imperative that children have a comprehensive vision exam.  These exams are often much different than those for adults.  Technology has enabled exams to occur with all ages.  Photoscreening is done in our office to provide objective results by the use of digital ocular images.  It is supported by recommendations of the American Academy of Pediatrics.  Preferential looking utilizes automatic brain reflexes in looking at closely spaced lined targets versus blank screens.  The brain will always look at targets if they can be seen.  Optokinetic nystagmus (OKN) testing gives information about how well a moving target is seen.  Differences between the eyes can also be indicative of strabismus.

--James B. Mayer, OD, FCOVD
     Agape Learning & Optometry Center
     Thousand Oaks, CA