Wide-Field Spectral-Domain Optical Coherence Tomography in Patients and Carriers of X-linked Retinoschisis

Abstract

To evaluate macular and extramacular retinal anatomy in patients and carriers of X-linked retinoschisis (XLRS) using a wide-field spectral-domain optical coherence tomography (SD-OCT) imaging technique. Case series. Six XLRS-affected male subjects and 3 XLRS female carriers. The subjects prospectively underwent XLRS DNA genotyping and comprehensive ophthalmic examination, including visual acuity, 30-2 Humphrey visual field, fundus photography, and wide-field SD-OCT, a montage technique to generate SD-OCT images spanning approximately 50 degrees horizontally and 35 degrees vertically of the posterior pole. Distribution and location of schisis cavities. Among male subjects affected by XLRS, asymmetric bilateral schisis was seen in all eyes imaged with montage SD-OCT (11 eyes). Wide-field OCT images demonstrated schisis cavities only in the central macula in 6 eyes (55%), throughout the macula extending to the outside of the temporal arcades in 3 eyes (27%), and throughout the macula extending nasal to the optic nerve in 2 eyes (18%). Cystoid spaces accounting for macular splitting were present in the inner nuclear layer (INL) in all 11 eyes and in the outer nuclear layer (ONL) in 4 eyes. A few small cysts were seen parafoveally in the ganglion cell layer (GCL) or nerve fiber layer (NFL) in 4 eyes. Subclinical extramacular schisis spaces were seen (n=5 eyes) within the INL in 1 eye, the ONL in 1 eye, the INL/GCL/NFL in 1 eye, the ONL/GCL/NFL in 1 eye, and the INL/ONL/GCL/NFL in 1 eye. Schisis was rarely seen nasal to the optic nerve (2 eyes). Central/paracentral visual field defects were seen in 9 eyes. Female carriers did not show schisis on examination or OCT. Wide-field SD-OCT is a useful tool for evaluating complex retinal anatomy. In patients with XLRS, the foveomacular schisis was seen most frequently in the INL. Subclinical extramacular schisis was seen in 45% of eyes and was equally prevalent in the INL, ONL, and GCL/FNL. The GCL/FNL cystoid spaces were small and seen near the fovea and the arcades only. Carriers were schisis-free. The author(s) have no proprietary or commercial interest in any materials discussed in this article.