Development of a new manufacturing process and control methods for intraocular lenses from innovative biomaterials

Abstract

Cataract surgery is the most frequently performed ophthalmologic surgery in the world. It consists in replacing the opaque crystalline lens with an intraocular implant. A large number of implants is available to meet the different expectations of patients. These lenses differ by the material used in their synthesis, their design and the optical performance brought to the patients.

PhysIOL is a company specialised in the production of intraocular lenses. In order to increase its production capacity, the company has developed the Sun project. The aim of this project is to develop a new process for manufacturing lenses by semi-moulding. This technique consists in moulding one side of the lens and machining the second one. This new semi-moulding process only concerns the production of hydrophobic intraocular lenses.

This master thesis focuses entirely on this new production process. The objective is to determine whether there are steps in the semi-moulding process that can be improved. Tests, called chemical tests, were performed to study the impact of different parameters on the properties of the polymer and to determine which validation tests are capable of identifying these impacts. Then, so-called mechanical tests were carried out. They focus on the cap removal stage and aim to reduce the rate of rejects. Finally, tests were carried out to remove the polymerised material from the mould. Influences of temperature, immersion in isopropanol and in an ultrasonic bath were studied.