Surfaces of silicone hydrogel contact lenses

The level of deposition usually found on silicone hydrogel lenses is minimal and deposition is more common toward the end of the 30-night wearing cycle. This is independent of whether the lenses are worn on a continuous or daily-wear schedule. However, some patients may be predisposed to develop higher levels of deposition more rapidly. We believe this may be due to the interaction of factors such as tear-film composition, ocular surface, environment, the lens material, and the relative stiffness of the lenses.