Deposits and make-up

Question:

View PDF 

Dr Cécile Maissa replies: Several material and patient-related factors have been shown to influence the deposition of tear film components on contact lens materials. In addition to the patient's tear film composition, contact lens material ionicity, water content, pore size and hydrophobicity influence the interaction between the patient tear film components and the contact lens.

Silicone hydrogel materials with the incorporation of siloxane moieties have greater hydrophobic properties than traditional hydrogel materials. Overall, SiHs have a propensity to attract lipids. They adsorb more lipids than traditional hydrogel lenses in in vitro and in ex vivo studies; however, the level of absorption varies between materials and is more marked for non-surface-coated materials.