Schisis-like Cystoid Macular Edema in Eyes with Diffuse Laser-treated Scars

Abstract

Purpose:We sought to describe the clinical and imaging characteristics of eyes with schisis-like cystoid macular edema (CME) with diffuse areas of laser scar and determine their relationships. Methods: This was a retrospective cross-sectional review of eight eyes with schisis-like CME with diffuse area of laser scar. Laser treatment was performed during retinal surgery in the same eye. Data were collected from May 2019 (the baseline assessment date) to May 2023. Areas of diffuse laser scarring were evaluated on widefield photographs. Layers of schisis-like lesions were evaluated manually on optical coherence tomography images. Any trends or differences were compared among eyes. Results: All eyes had splitting between the inner nuclear and outer plexiform layers. Three eyes had additional splitting between the outer nuclear and outer plexiform layers. Four eyes achieved CME reductions by intravitreal triamcinolone treatment. Regions of retinal laser scar were infero-temporal in four cases, infero-nasal in one case, supero-temporal in one case, and both infero-nasal and infero-temporal in two cases. The location of schisis-like CME was infero-temporal in four cases, inferior in one case, supero-temporal in one case, infero-nasal in two cases, and of uniform distribution in one case. The locations of diffuse laser scars and the locations of schisis-like CME showed correspondence. Conclusions: A wide area of laser-applied scar on the retina may contribute to the development of schisis-like CME through multiple factors, including tractional force, vascular endothelial growth factors, and inflammation.