Effect of heparin surface modification in reducing silicone oil adherence to various intraocular lenses

Purpose: To evaluate surface properties of various intraocular lenses (IOLs ), including a newly fabricated heparin-surface-modified (HSM) silicone IOL , with special reference to their efficiency in reducing potential silicone oil adherence to the IOL optics. Setting: Center for Research on Ocular Therapeutics and Biodevices, Departm ent of Ophthalmology, Storm Eye Institute, Medical University of South Caro lina, Charleston, South Carolina, USA. Methods: Five groups of rigid and foldable IOLs were analyzed in an in vitr o test for the percentage of silicone oil adherence: a single-piece foldabl e hydrophilic-acrylic IOL (n = 9); a single-piece rigid poly(methyl methacr ylate) (PMMA) IOL with HSM coating of the lens optic (n = 9); a 3-piece fol dable silicone optic IOL with HSM coating of the optic (n = 10); a single-p iece standard rigid PMMA IOL (n = 7); and a standard 3-piece foldable silic one optic IOL (n = 9). After the IOLs were immersed in water and then in si licone oil, gross photographs taken. Image analysis was performed to evalua te the percentage of silicone oil coverage of the anterior and posterior su rfaces of each IOL optic. Results: The mean silicone oil coverage of the hydrophilic-acrylic IOLs was 5.6% +/- 2.5% (SID); of the HSM PMMA IOLs, 6.2% +/- 4.3%; of the HSM silic one optic IOLs, 6.7% +/- 3.2%; and of the standard PMMA IOLs, 20.3% +/- 13. 3%. The mean silicone oil coverage was greatest on the standard silicone op tic IOLs, 98.2% +/- 3.1 %. Conclusions: Intraocular lenses with a hydrophilic optic have less tendency toward adherence to silicone oil than more hydrophobic designs. A foldable silicone IOL with heparin surface modification can significantly reduce po tential silicone oil adherence, comparable to the level achievable with the rigid HSM PMMA designs. Two new foldable IOL styles, the HSM silicone IOL and IOLs in the general class of hydrophilic-acrylic, were highly efficacio us in reducing silicone oil adherence. There is now a real choice of foldab le lenses for patients with actual or potential vitreoretinal diseases. (C) 2001 ASCRS and ESCRS.