Purpose: To compare the ocular toxicity caused by the use of highly purified silicone oil to less purified silicone oil in humans.
Methods: Fifty-six eyes received 2,000 centistokes (cs) purified silicone oil (group 1) and 42 eyes received 2,000 cs fractionated (highly purified) silicone oil (group 2) after pars plana vitrectormy. Follow-up ranged from 6 to 48 months.
Results: Six months after injection, the following complications were found in groups 1 and 2, respectively: ocular hypotension (< 13 mmHg), 39.3% and 31%, sustained ocular hypertension (> 23 mmHg), 19.6% and 19%; acute hypertensive peaks (> 30 mmHg), 23.2% and 11.9%; corneal alterations, 19.6% and 14.3%; emulsification, 1.8% and 2.4%; silicone oil cloudiness, 28.6% and 0%; preretinal reproliferation, 14.3% and 4.8% and total or partial retinal reattachment, 78.6% and 90.5%.
Conclusions: Highly purified silicone oil was better tolerated than the less purified oil and caused fewer complications. Poorly purified silicone oils should be avoided in clinical practice.