Purpose Large relaxing retinectomies have become increasingly used in the repair of retinal detachment related to proliferative vitreoretinopathy (PVR). Retinectomies expose the retinal pigment epithelium (RPE) to the vitreous cavity; the direct effects of silicone oil on the RPE are only beginning to be understood. Design Retrospective case series. Participants Twelve patients noted to develop pigmented epiretinal deposits at regularly scheduled follow-up visits after repair of complex retinal detachments using silicone oil tamponade and retinectomy. Methods Epiretinal pigment deposits were characterized clinically by wide-field color photography, fundus autofluorescence imaging, and spectral-domain optical coherence tomography (SD OCT). At the time of silicone oil removal, the pigmented membranes were preserved in fixative and analyzed by light microscopy/immunostaining or electron microscopy for histologic characterization. Main Outcome Measures Not applicable. Results We describe the development of diffuse preretinal pigmentary deposits in 12 eyes after surgery for complicated PVR detachments using retinectomies with oil, with an average onset of 3.2 months postoperatively. These pigment clumps produced a striking leopard-spot pattern on fundus autofluorescence imaging. Histopathologic and ultrastructural analysis of these epiretinal proliferations peeled at the time of silicone oil removal revealed RPE cells with intracellular silicone oil droplets, singly dispersed membrane-bound melanin granules, glial tissue (1 case), and a fibrous stroma. Conclusions Although in vitro studies have suggested that RPE cells can phagocytose emulsified oil droplets, this report represents the first in vivo documentation by electron microscopy of this phenomenon in patients. These findings underscore that direct contact with silicone oil may affect the behavior of the RPE, which may be clinically relevant in patients who have undergone large relaxing retinectomies with silicone oil tamponade for PVR-related retinal detachments.
ASJC Scopus subject areas