X-linked retinoschisis: OCT-angiography in two brothers from a four-generation family with a p.Arg197Cys pathogenic variant in the RS1 gene.

Abstract

X-linked juvenile retinoschisis (XLRS) is a rare genetic disease causing retinal splitting. The aim of this work is to describe the optical coherence tomography angiography (OCTA) features in two brothers affected by an hemizygous c.589C>T (p.Arg197Cys) pathogenic variant in exon 6 of the RS1 gene. Each patient underwent a complete ophthalmological examination, including measurement of best corrected visual acuity, slit-lamp biomicroscopy, fundus color photographs, fundus autofluorescence and infrared imaging, fluorescein angiography, spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA). En Face SD-OCT and OCTA revealed the presence of two different pattern of cystic lesions, fusiform and oval, disposed on a petaloid or irregular manner in the perifoveolar area. A widening of the foveal avascular zone with interruption of the vascular arcades was clearly evident. Furthermore, a capillary drop-out was observed in the superficial plexus of the central retina, other than capillary ectasia in the deep capillary plexus. Straight gray lines were visible among the cysts. OCTA data herein described allow a detailed morphological evaluation of XLRS other than a quantitative assessment of retinal capillary flow in this disease. The retinal alterations that we have reported may be helpful to better understand this rare condition with OCTA being a sensitive technique to monitor the evolution of the disease and the response to potential future therapeutic approaches aimed to restore vision.