Prevalence of Ocular Pathology on Initial Screening and Incidence of new findings on Follow up Examinations in Children with Trisomy 21

Purpose Various ophthalmologic findings have been associated with Trisomy 21. However, prior studies on this topic are limited by their sample size and the lack of follow-up regarding the incidence of new pathology after an initially normal exam. We determined whether children who have a normal first examination need to have formal re-evaluation by an ophthalmologist. Design Retrospective Cohort Study Methods Records were reviewed for 689 patients with Trisomy 21 evaluated at Vanderbilt Eye Institute between 2012 and 2017. Ocular and refractive abnormalities present on initial screening were recorded and follow up data were reviewed to determine if new abnormalities developed at subsequent visits. Results 410 of the 689 (59.5%) patients had a significant finding on their first examination. The most common abnormalities seen on initial screening examination were strabismus, significant refractive error, and eyelid abnormalities (including ectropion and accessory puncta). 179 of the 279 initially normal patients had at least one follow up visit at a mean follow up interval of 21.6 months (average age 3.7 years). At the first follow up visit, 129 remained normal, while 50 had a new abnormality; most commonly significant refractive error and strabismus. On second follow up visit, at a mean follow up interval of 12 months (average age 4.8 years), 63% remained normal. Conclusions Ocular pathology occurs in Trisomy 21 at a much higher prevalence than the general population; thus these children initially should have a comprehensive eye examination. While the development of new ocular pathology in a child with Trisomy 21 and a previously normal exam is not unusual, most of these new abnormalities are detectable with automated vision screening techniques or direct visual inspection of the eyes and ocular adnexa; thus once a child has a normal examination, a formal vision screening could replace a formal ophthalmologic examination.