Cellular-Level Assessment of Macular Development in Patients With Familial Exudative Vitreoretinopathy Using Multimodal Imaging: A Prospective Cohort Study.

Abstract

To investigate the multimodal characteristics of macula in patients with familial exudative vitreoretinopathy (FEVR) at a cellular level. Prospective cohort study. A total of 46 FEVR-affected and healthy eyes were enrolled from July to October 2024 and underwent multimodal examinations. Participants with conditions such as foveal hypoplasia (FH), a history of ocular surgery, or trauma in both the control and FEVR groups were excluded. All participants underwent examinations of scanning laser ophthalmoscopy (SLO), ultra-wide-field swept source optical coherence tomography angiography (UWF SS-OCTA), and adaptive optics (AO)-SLO to acquire metrics of multimodal macular characteristics such as macular appearance, layered structure, vasculature, and photoreceptor distribution. The baseline information such as best-corrected visual acuity (BCVA), spherical equivalent (SE), and axial length (AL) were also measured. Compared with age- (9.76 years on average), gender- (52% female), SE- (-1.01 D on average), and AL-matched (23.66 mm on average) healthy eyes, FEVR-affected eyes without FH had increased foveal avascular zone (FAZ) perimeter in deep capillary plexus (DCP), partly thickening inner retina layers and thinning outer nuclear layer, as well as partly lower vessel density of DCP (P < .05). At the cellular level, eyes with FEVR showed numerically lower cone density and larger cone spacing in fovea, but significantly higher cone density (P = .03) and smaller cone spacing (P = .02) in the parafovea, as well as higher cone dispersion and lower regularity (P < .05). Foveal and parafoveal cone density in participants with low BCVA were numerically higher. Patients with FEVR without FH may be characterized by irregular FAZ morphology and cone distribution, exhibiting lower foveal and higher parafoveal cone densities, which was not correlated with their BCVA and may serve as clinical biomarkers for diagnostic assistance in FEVR. Participants with low BCVA but morphologically normal macular structure may harbor underlying cone abnormalities, underscoring the necessity for more thorough assessment, warranting greater caution in diagnosing amblyopia until exclusion of the influence of cellular-level abnormalities.