Abstract
Purpose: :
To determine whether an automated device designed to detect refractive overcorrection in adults could be used to detect occult accommodative–convergence deficits or strabismus in children.
Methods: :
39 children who presented to a community pediatric ophthalmic practice underwent comprehensive clinical and orthoptic assessment. Among these patients, 24 (13M/11F; mean age 8.9 yrs) were found to have clinically significant convergence insufficiency or strabismus, and 15 (8M/7F; mean age 9.6 yrs) demonstrated no clinical abnormality on standard testing. All 39 children completed a 3–minute test with the TriIris C9000 automated dynamic pupillometer (Hamamatsu; Hamamatsu, Japan), which dynamically monitors bilateral pupil position (convergence/divergence) and pupil diameter (miosis/mydriasis) via 2 CCD cameras as a tri–chromic accommodative stimulus is moved in and out from far point to near point at a rate of 1 diopter/sec (3 cycles in 3 min). The rate of inward/outward stimulus excursion is thus slower than nearer its distance to its subject. Printouts of the binocular traces for convergence and pupillary diameter for the 39 subjects were coded, randomized, and subjectively assessed as normal (0), abnormal (3), or inconclusive (1) by a pediatric ophthalmologist (CM), an orthoptist (CH), an eye resident (GL) and a non–pediatric ophthalmologist (WES). The independent masked scores of all 4 judges were tallied for each subject, and those with a cumulative score ≥4 were deemed positive.
Results: :
Among 24 children with accommodative esotropia (n=17) or strabismus (n=7), the mean defect score was 6.75 with 19 (79%) screening positively. Among 15 referral patients failing to demonstrate clinical abnormality, the mean defect score was 3.0 with 10 (67%) screening negatively.
Conclusions: :
Accommodative insufficiency and strabismus may contribute significantly to learning disabilities of school age children. The unadapted TriIris adult pupillometer appears to have potential as a screening device for this age group. Ancillary evidence from this study population indicates that a shorter test (1 minute) with a nanotechnologic animated stimulus may enhance its practicability and specificity.
Keywords: eye movements • strabismus: diagnosis and detection • pupillary reflex