Analysis of the Time and Location of the Silicone Oil Emulsification by Spectral-Domain Optical Coherence Tomography after Silicone Oil Tamponade

Purpose. To estimate localization and the period up to the appearance of small hyperreflective round-shaped droplets using spectral-domain optical coherence tomography (SD-OCT) after pars plana vitrectomy with silicone oil tamponade. Methods. A retrospective observational study included 24 patients who had undergone pars plana vitrectomy with silicone oil tamponade for proliferative vitreoretinopathy (PVR) retinal detachment. SD-OCT analysis was performed 1, 3, and 6 months after surgery. We characterized the emulsified silicone oil in the SD-OCT as the small hyperreflective round-shaped droplets. Results. In SD-OCT examination, none of the patients had hyperreflective round-shaped droplets visible one month after vitrectomy with silicone oil tamponade. The hyperreflective droplets were found three months after surgery—in one patient above the optic nerve and in five patients intraretinally (in the cystoid spaces). Six months after vitrectomy, the hyperreflective round-shaped droplets were still present in the aforementioned patients' eyes and additionally in 3 eyes above the optic disc. Conclusions. Hyperreflective round-shaped droplets were found in a SD-OCT examination 3 months after silicone oil tamponade. The authors suggest that they are most likely the emulsified silicone oil droplets. The authors hypothesize that emulsification and migration of silicone oil begin within 3 months after surgery.