Multimodal imaging and histopathological evaluation in silicone oil keratopathy

Purpose: To describe features in silicone oil keratopathy using multimodal imaging and histopathological examination. Methods: Case report Result: A 21-year-old male developed right corneal decompensation in the heavy SO (HSO)-filled eye. The patient underwent an initial lensectomy, pars plana vitrectomy (PPV) and HSO tamponade due open-globe injury with corneal wound, lens damage and in two retained intravitreal glass foreign bodies, followed by a revisional PPV with HSO tamponade due to tractional detachment associated with proliferative vitreoretinopathy and epiretinal membrane. One month after the removal of HSO, ophthalmic examination of the right eye showed corneal decompensation. The AS-OCT showed corneal thickening, intrastromal scattered hyperreflective dots and large rounded/oval hyporeflective space; the latter were suggestive of emulsified HSO microbubbles and larger bubbles, respectively. In vivo confocal microscopy showed multiple presumed SO-related corneal changes, including hyper-reflective fibrotic changes in the basal epithelium, reduced density ans altered morphology of keratocytes cell population, increased pleomorphism and polymegathism of the endothelium with reduced endothelial cell, and presence of inflammatory cells. The patient underwent a penetrating keratoplasty, pupilloplasty and retropupillary iris-claw IOL implantation. The histopathological examination of the host corneal button showed Descemet's membrane irregularity and thickened corneal stroma with focal intrastromal silicone oil vacuoles, surrounded by macrophages. Conclusion: We described for the first time intrastromal hyperreflective dots as a sign associated with SO-related keratopathy. Moreover, this case report supports the ability of emulsified SO to penetrate the cornea inducing a local low-grade chronic inflammation.