Dedifferentiation of retinal pigment epithelium in a patient with chronic retinal detachment

A 34-year-old woman presented with vision loss in her right eye, which had persisted for approximately 12 months. Funduscopy showed horseshoe retinal tear at the 8-o'clock position and retinal detachment in inferior, nasal, and temporal quadrants, with a pigmented demarcation line in the right eye. Diffuse punctate accumulations were noted on the detached retinal surface and in the vitreous. Fundus autofluorescence imaging detected diffuse punctate accumulations, which produced hyperautofluorescence spots. Cytological examination of a vitreous sample detected CD68-positive and cytokeratin- and CD45-negative macrophages. These findings indicate that epithelial-to-mesenchymal transition occurred in the retinal pigment epithelium of our patient.