Towards Cognition-Guided Patient-Specific Numerical Simulation for Cardiac Surgery Assistance

Motivation. Patient-specific, knowledge-based, holistic surgical treatment planning is of utmost importance when dealing with complex surgery. Surgeons need to account for all available medical patient data, keep track of technical developments, and stay on top of current surgical expert knowledge to define a suitable surgical treatment strategy. There is a large potential for computer assistance, also, and in particular, regarding surgery simulation which gives surgeons the opportunity not only to plan but to simulate, too, some steps of an intervention and to forecast relevant surgical situations. Purpose. In this work, we particularly look at mitral valve reconstruction (MVR) surgery, which is to re-establish the functionality of an incompetent mitral valve (MV) through implantation of an artificial ring that reshapes the valvular morphology. We aim at supporting MVR by providing surgeons with biomechanical FEM-based MVR surgery simulations that enable them to assess the simulated behavior of the MV after an MVR. However, according to the above requirements, such surgery simulation is really beneficial to surgeons only if it is patient-specific, surgical expert knowledge-based, comprehensive in terms of the underlying model and the patient’s data, and if its setup and execution is fully automated and integrated into the surgical treatment workflow. Methods. This PhD work conducts research on simulation-enhanced, cognition-guided, patient-specific cardiac surgery assistance. First, we derive a biomechanical MV/MVR model and develop an FEM-based MVR surgery simulation using the FEM software toolkit HiFlow3. Following, we outline the functionality and features of the Medical Simulation Markup Language (MSML) and how it simplifies the biomechanical modeling workflow. It is then detailed, how, by means of the MSML and a set of dedicated MVR simulation reprocessing operators, patient-individual medical data can comprehensively be analyzed and processed in order for the fully automated setup of MVR simulation scenarios. Finally, the presented work is integrated into the cognitive system architecture of the joint research project Cognition-Guided Surgery. We particularly look at its semantic knowledge and data infrastructure as well as at the setup of its cognitive software components, which eventually facilitate cognition-guidance and patient-specifity for the overall simulation-enhanced MVR assistance pipeline. Results and Discussion. We have proposed and implemented, for the first time, a prototypic system for simulation-enhanced, cognition-guided, patient-specific cardiac surgery assistance. The overall system was evaluated in terms of functionality and performance. Through its cognitive, data-driven pipeline setup, medical patient data and surgical information is analyzed and processed comprehensively, efficiently and fully automatically, and the hence set-up simulation scenarios yield reliable, patient-specific MVR surgery simulation results. This indicates the system’s usability and applicability. The proposed work thus presents an important step towards a simulation-enhanced, cognition-guided, patient-specific cardiac surgery assistance, and can – once operative – be expected to significantly enhance MVR surgery. Concluding, we discuss possible further research contents and promising applications to build upon the presented work

Integrated Design, Design Management and the Delivery of Major Hospitals

There is a failure to fully achieve client expectations and to deliver integrated hospital building solutions that function to all spatial and equipment requirements. Often this is because the construction of hospitals is based on designs established several years before the start on site. A retrospective abductive, auto-ethnographic case study approach has been taken in the examination of four major hospital projects over a period of 30 years. The level of design integration and effect of design management and coordination issues relating to stakeholder engagement, roles and responsibilities, static and dynamic briefing and the integration of major medical equipment has been explored at a project level, then contextualised within a wider delivery model to understand the impacts of these on integrated delivery and systems integration. Five temporal periods were observed, four of them relating to the retrospective case studies these were: (1) prescriptive integration – where traditional procurement with Design, Bid, Build delivery was combined with standards and guidance; (2) dysfunctional integration – where the adoption of Private Finance Initiative (PFI) with Design and Build delivery transferred traditional roles and reduced standardisation; (3 and 4) adaptive integration 1 and 2 – which saw both a gradual deregulation of standards; and, an understanding for standards, and (5) the fifth temporal disintegration period – where guidance from the wider delivery model ceased to be updated due to top down policy reorganisation and lack of centralised control and includes a current case study. Throughout these temporal periods, it was found that the national delivery models have had a significant influence on hospital project delivery and particularly systems of systems integration. A new model based on layering principles that shows the impact of wider delivery models on systems integration is proposed to improve the provision of ‘state of the art’ facilities at project completio