Biomechanical Modelling of the Human Eye

The goal of this work was the development of a biomechanical model of the human eye. An interactive software system was implemented, called „SEE++“ which allows also physicians to obtain a better understanding of the mechanics of eye movements. This software visualizes and simulates pathologies and eye muscle surgeries, based on the biomechanics of the eye. It can be used in preoperative planning, medical training and basic research, and shows how MedicalInformatics can improve the diagnosis and treatment of patients. The interdisciplinary nature of the project required contributions from very different fields. Anatomical studies, in cooperation with researchers as well as practicing physicians, provided data for defining a mathematical representation of human eye movements. The biomechanical model included a geometrical representation of eye movements, a muscle force prediction model, and a kinematic model that balances muscle forces by using mathematical optimization methods. High-resolution magnetic resonance imaging studies were carried out to visualize eye muscle morphology, and image processing methods used to reconstruct three dimensional approximation models of human eye muscles. Modern software engineering methods provided the basis for an extensible object-oriented software design. Three dimensional interactive visualization and a user interface optimized for medical use were combined into a unique software simulation system for the clinic and for teaching. The „SEE++“ software system is currently the most advanced biomechanical representation of the human eye, with respect to simulating eye movements and eye muscle surgeries. The extensive possibilities for parametrization of the human eye model allow interactive simulations of pathological cases and surgical corrections, and the predictions correspond well with clinical data. This system is used in various clinical facilities as computer aided decision support for strabismus (squint) surgeries. In medical training and education, it substantially improves the functional understanding of human eye movements.