Ophthalmic Manifestations of Williams Syndrome

Abstract

Purpose : Williams syndrome (WS) is an inherited disorder caused by microdeletions of chromosome 7q11.23, including ELN. Hemizygosity for the ELN gene accounts for many of the connective-tissue abnormalities seen in this syndrome. The purpose of this study is to describe the ophthalmic features of these patients.

Methods : Patients with WS were evaluated at the National Institutes of Health as part of a prospective study, Impact of Elastin Mediated Vascular Stiffness on End Organs (NCT02840448). Participants were examined and the following data was analyzed: demographics, visual acuity, color vision, anterior segment and dilated eye exam, biometry, optical coherence tomography (OCT) and ophthalmic imaging.

Results : Fifty-one patients with WS were evaluated at the National Eye Institute between 2017 and 2019. The mean age of patients examined was 20.2 years (range 3-60 years), with 26 females and 25 males. Mean best corrected visual acuity of the cohort was 20/30 OD, 20/40 OS (range 20/20-20/400) with a mean spherical equivalent of plano (range OD -5 to +8.50, OS -5 to +6.50). Axial length measurements (N=50) ranged from 18.6 mm to 24.2 mm with a mean of 21.5 mm. Fifteen patients (29.4%) had strabismus at the time of their evaluation. Color vision was normal based on Ishihara testing with a mean of 15.6 of 16 color plates identified in each eye (N=46). Twenty-three patients (45.4%) had the classically described finding of stellate iris and one patient had mild anterior segment dysgenesis. Of the 37 patients who were able to complete OCT imaging, only 7 (13.7%) had a classically normal foveal contour while the remaining patients had a wider and deeper foveal pit. Thirty-nine patients (76.5%) had tortuous retinal vessels and only one patient had signs of previous retinal vascular occlusion.

Conclusions : Williams syndrome was first identified as a distinct entity in 1961 and since then, few groups have reported on the ophthalmic findings. We present the first prospective study evaluating WS patients systematically and report on the classically described findings of stellate iris, strabismus and hyperopia as well as novel structural retinal findings. We find a lower overall rate of hyperopia and a much higher rate of tortuous retinal vessels in our cohort as compared to that described in the literature. Future work correlating these ophthalmic findings with collected systemic data, may provide further insight into elastin mediated vascular disease.

This is a 2020 ARVO Annual Meeting abstract.