Abstract
Purpose :
Williams-Beuren Syndrome (WBS) is a complex genetic disorder caused by a microdeletion on chromosome 7q11.23. This work aims to provide a detailed description of foveal features in WBS through quantitative metrics and qualitative classification.
Methods :
Individuals with WBS who were examined at the National Institutes of Health as part of the Impact of Elastin Mediated Vascular Stiffness on End Organs study and had Optical Coherence Tomography (OCT) were included in this analysis. The inner limiting membrane and retinal pigment epithelium were manually segmented on foveal OCT scans and processed for pit diameter (PD), foveal slope (FS) and central foveal thickness (CFT). Scans were qualitatively classified as broad if they had a widened area of extrusion of the inner retinal layers or widened PD. Mann-Whitney, Fisher’s Exact test and Spearman correlations were used for analyses.
Results :
Forty-four WBS patients were included in this study; 21 males and 23 females, 77.3% identifying as non-Hispanic White, with a median age of 22 years (range 5-60 years). Mean best-corrected visual acuity (BCVA) was 20/30 (range 20/20-20/100) OU. Imaging of the right eye of one patient and the left eye of two patients was excluded for poor quality. Mean PD was 1832 μm (range 1195-2345 μm) OD and 1836 μm (range 1278-2304 μm) OS, strongly correlated between eyes (R=0.84, p<0.001). CFT had a moderate inter-eye correlation (R=0.56, p<0.001), mean 186 μm (range 157-250 μm) OD and 187 μm (range 166-234 μm) OS, which is thinner than reported healthy population means. FS was also correlated between eyes (Nasal R=0.78, p<0.001; Temporal R=0.62, p<0.001). Subgroup analyses were performed on those qualitatively classified as broad fovea (N=36, 81.8%) and normal; there was no significant difference in BCVA, refractive error, age, or sex between groups. PD was significantly wider (p≤0.003) and CFT was thinner (p=0.002) in the broad fovea group, while FS did not differ between groups. Thinner CFT was not correlated with BCVA.
Conclusions :
This study provides foveal metrics in a cohort of WBS patients, showing a thinned CFT and quantitatively widened PD in eyes with a qualitatively broad fovea, despite a largely White racial identity and balanced sex representation in the cohort. We postulate this foveal morphology is associated with the WBS microdeletion region, supporting the need for future studies of WBS to help understand the molecular basis of foveal development.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.