: Patient-adaptive pressure monitoring and treatment system for glaucoma therapy

An important aspect of the surgical technique of the novel implant system designed here is a low-complication and safe execution: The microsurgical implantation and fixation of an ophthalmological implant are demanding and require a high level of skill on the surgeon's part. Immediately after the operation, phases of hypotony can occur due to a lack of tightness of the connection between the implant and the tissue. Above all, in addition to a secure fixation through a sustainable integration into the tissue, a function undisturbed by cell growth must be guaranteed at the same time. With the planned project, it should be possible to regulate the dynamics of the intraocular pressure individually for each patient on the basis of current measurements accompanying the therapy.

The IFUM sub-project is concerned with the construction of a numerical model based on the finite element method (FEM), which enables numerical investigations of the implant-eye system. To carry out the simulation, information is needed that describes the system to be modelled. In the case of the glaucoma implant, a model must be generated that approximately accurately captures the anatomy of the eye with the glaucoma implant inserted by trabeculectomy. For this purpose, data must be available in advance as input variables. These data are determined by the project partners through tomographic analyses of the eye bulb to create a collection of information on the various chambers and tissue components, and are supplemented by tonometric measurements. These data are provided in digitised form for the FE modelling.

Furthermore, for the numerical modelling of the implant-eye system, the most accurate possible physical description of the materials of the implant as well as the different scleral layers is essential. In particular, the material description of the actuator made of a shape memory alloy in the glaucoma implant requires cooperation with the project partners, who provide the experimental data as a basis for the numerical modelling through a material characterisation. The validation of the generated material model or simulation model is also carried out in collaboration with the project partners on a functional model, the development of which is carried out by them in parallel.