Cilioretinal vessels in adult twins

Abstract

Abstract: : Purpose: Cilioretinal vessels are a common anatomical variant connecting the ciliary with the retinal circulation. Their presence may influence the clinical severity of diseases such as retinal artery occlusion, retinal vein occlusion or glaucoma. Little is known about the heritability of vascular branching patterns. Twin studies of the retinal vasculature provide an opportunity to estimate the relative importance of genes and environment in the development of vascular branching patterns. Methods: We studied 104 sets of adult twins from the Twins Eye Study in Tasmania who had optic disc stereo photographs available. Results: 49 MZ pairs and 55 DZ pairs were evaluated. 85 of 208 eyes had a cilioretinal vessel. For the MZ pairs, 27 had normal vasculature, 14 had ¼ eyes affected, 1 had the same eye affected, 3 had mirrored eye affected, 3 had both eyes of only one twin affected, 1 had 3 eyes affected and none 4 eyes affected. For the DZ pairs, 21 had normal vasculature, 18 had ¼ eyes affected, 4 had the same eye affected, 2 had mirrored eye affected, 7 had both eyes of only one twin affected, 2 had 3 eyes affected and 1 had 4 eyes affected. Conclusions: There does not seem to be a major heritable component to the presence of cilioretinal vessels. However, when a solitary cilioretinal vessel was present, the eye of the identical twin often had a matching retinal vessel.

Keywords: retina • genetics • blood supply