Ocular cytotoxicity evaluation of medical devices such as contact lens solutions and benefits of a rinse step in cleaning procedure

Contact lens care solutions are known to have toxic effects on the ocular surface. The ISO 10993-5 standard describes test methods to assess the cytotoxicity of medical devices, but it needs some improvements to discriminate contact lens care multipurpose solutions. First we evaluated the biological hazards associated with the use of ophthalmic solutions, running a collaborative study with the French medical agency to propose adapted tools to study contact lens care solutions' ocular cytotoxicity (human cell line, short incubation times, and no dilution of solutions to test). Then we took into account the potential risk of these ophthalmic solutions adsorbed on contact lenses and released on the ocular surface, highlighting the addition of a rinse step with unpreserved marine solution in the contact lens cleaning procedure to avoid side effects of contact lens care solutions.