Time effect on silicone oil emulsion formed in a model of the eye vitreous chamber

Introduction: Silicone oil (SO) is widely used as a long-term intraocular tamponade following pars plana vitrectomy (PPV) for complex retinal conditions. However, its emulsification is associated with serious complications, including intraocular inflammation and glaucoma. While various factors influencing this process have been explored, the role of time in SO emulsification remains unclear. This study investigates the movement time effect on SO emulsification using a physiologically realistic model, with a focus on changes in droplet size distribution and emulsion density. Methods: A 3D-printed, anatomically accurate model of the human vitreous chamber was filled with SO and an albumin-containing aqueous phase, maintained at 35°C. Experiments were conducted with varying albumin concentrations and saccadic eye movements of different amplitudes. Emulsions were sampled and analyzed after 6, 12, and 24 hours, and 6 days. Results: Emulsification was observed under all conditions. Over time, the number of smaller droplets increased, and emulsion density rose sharply within the first 12 hours, followed by a slower progression. Higher albumin levels and larger saccadic amplitudes promoted more extensive emulsification. Conclusion: These findings identify the early postoperative period, particularly the first 12 hours, as critical for SO emulsification.