Characterization and diagnosis of retinoschisis and schisis detachments using spectral domain optical coherence tomography.

Purpose: To characterize retinoschisis in a large series using spectral domain optical coherence tomography (SD-OCT), including rates of schisis detachment and macular involvement in cases of peripheral retinoschisis.

Methods: In this retrospective, cross-sectional, descriptive study, consecutive patients with diagnosis of retinoschisis in at least one eye were identified using billing codes between January 2012 and May 2021. Charts were reviewed to verify diagnosis of retinoschisis or schisis detachment. SD-OCT and clinical examination was used to identify frequency of macular schisis, peripheral schisis, and schisis detachment, and characteristics of retinoschisis including frequency of inner and outer wall breaks, distribution of layers split, and location of involvement of peripheral pathology. SD-OCT images of insufficient quality were excluded from the pertinent analysis.

Results: 281 eyes of 191 patients were included. 195 (69.4%) eyes had peripheral retinoschisis, 15 (5.3%) had schisis detachment, 66 (23.5%) had macular retinoschisis alone, and 5 (1.8%) had combined macular and peripheral retinoschisis. Of the eyes without macular retinoschisis, 7.0% had schisis detachment. Of the remainder, 4 (2.1%) had inner wall breaks, and 24 (12.3%) had outer wall breaks. In eyes with peripheral retinoschisis, splitting occurred in the outer plexiform layer in 58.9%, the retinal nerve fiber layer in 8.9%, a combination of layers in 26.8%, and indeterminate in 5.4%. Location of peripheral involvement was inferotemporal in 58.5%, superotemporal in 14.1%, temporal in 13.7%, and inferior in 12.2%.

Conclusion: SD-OCT helped to identify the presence of schisis detachment and breaks, confirmed diagnosis in challenging cases, and demonstrated the layer of splitting within the neurosensory retina. This series represents the largest such study to date.