Retinoschisis in eyes with pachychoroid and retinal pigment epithelial atrophy

Purpose: To describe the clinical characteristics and courses for eyes with retinoschisis associated with pachychoroid. Methods: A retrospective interventional case series study. Twenty-one eyes (18 patients) with pachychoroid that showed retinoschisis without evidence of neovascularization that had been followed for 1 year were included. Multimodal imaging, including fundus photography, spectral-domain optical coherence tomography (OCT) with an enhanced depth protocol, fluorescein angiography (FA), and indocyanine green angiography (ICGA), was provided and treatment outcomes were analyzed. Results: Focal RPE atrophy was present below or adjacent to the schisis in all eyes, and the mean atrophy area was 1.38 ± 1.37 mm². Intraretinal fluids of the schisis originated from the atrophy area and involved the retinal layer which was correlated with the extent of outer retinal defect. Dilated Haller layer vessel and choroidal vascular hyperpermeability were observed under the area with atrophy in all eyes. After 1 year of treatment, 11 eyes (52%) still had fluid and 7 of them had fluid at the macula. Nonetheless, the mean central macular thickness decreased (144.4 to 121.8, P < 0.001), visual acuity improved (0.65 to 0.47, P = 0.026), and subfoveal choroidal thickness decreased (442.2 μm to 394.9 μm, P < 0.001). Conclusion: Atrophy of RPE can cause retinoschisis in eyes with pachychoroid. The intraretinal fluid that originated from underlying choroid and choroidal thickness decreased as intraretinal fluid diminished.