MODELLING AND SIMULATION
device designers are also collaborating at a growing rate. Such cross-discipline work is facilitated
through simulation applications, according to Marra, who added: ‘Such apps allow the users to input the parameters needed to get the information they need, the stress in a bone structure or the temperature rise during an ablation process, without having to deal with the complexity of a multiphysics model, something their fellow simulation specialists took care of for them.’
SimScale has also developed a
production-ready SaaS application for engineering simulation. It provides instant access to computational fluid dynamics and finite element analysis via a user- friendly web application. Mafi explained: ‘In general, our users use simulation with SimScale to test cardiovascular stents, hip joint or arm prostheses, disposable pumps, in vivo blood flow or laboratory equipment.’
Multiphysics simulation of tumour ablation. The localised heating of malignant tissue is achieved through the insertion of a four-armed electric probe. This model couples the bioheat and electric field equations, and models the temperature field in the tissue
ensure we fully understand the limitations of the current models.’ The human body is also a very
different environment compared to the systems regularly simulated in established industries, such as aerospace or automotive. Milad Mafi, product marketing manager at SimScale, said: ‘The biggest challenge from a simulation setup perspective is definitely geometry modelling. Simulation has its roots in classical mechanical engineering and all concepts and processes developed in recent years are designed for technical geometries and materials.’ A good example is the material
characterisation of steel compared to bone. Mafi explained: ‘While metallic materials can be described by isotropic material models, this is often not possible with biological materials. The bone gains high stiffness from the complex microstructures, which move in geometric scales of a few micrometres and cannot be resolved with current methods. It is, therefore, necessary to supply replacement models that are both technically and medically suitable.’
Restrictive regulations These models also need to be validated to demonstrate that the model does accurately predict what will happen in the human body for various patients. Ansys
www.scientific-computing.com | @scwmagazine
“While system-level modelling is something that companies in other industries such as aerospace and automotive have been using for decades, it is becoming a more popular tool in the medical device market”
recently collaborated with medical device companies, under the guidance of the FDA and ASME regulatory bodies, to address this point and develop new standards for the verification and validation of medical devices.
Such close collaboration between simulation companies and regulatory authorities could help accelerate adoption in the medical devices market. Ansys has also collaborated with numerous hospitals around the world and regulatory authorities in Europe, the USA and Asia. Marchal said: ‘This [collaboration with regulators] is helping us understand what these local agencies and European Notified Bodies require in terms of model validation and results format to accept simulation results as evidence for their respective regulatory approval.’ It’s not just collaboration with regulators that will help drive further adoption of simulation and modelling in the medical devices arena. Simulation experts and
Abundant applications A wealth of application areas are now emerging in the medical devices sector. Mafi added: ‘In my opinion, the leading star is the availability of patient-specific implants. Especially in the treatment of diseases of the cardiovascular system, such as arteriosclerosis but also in the treatment with joint replacement, simulation offers an unbelievable potential. FEA and CFD analysis play a decisive role in this context and will increasingly act as a catalyst in the coming years.’ Simulation and modelling are also helping the healthcare industry develop artificial biocompatible organs, such as an artificial heart, kidney and pancreas. Marchal explained: ‘These devices are expected to be implanted into patients for an extended time. Thanks to simulation, their size, weight and necessary energy to support them are now compatible with patients’ and medical professionals’ expectation. This solution may soon solve the problem of lacking organ donors.’ Another emerging area is the adoption of simulation in surgical planning. Marchal explained: ‘Creating a computer model of part of a patient gives the surgeon the luxury to test different surgical approaches, identify potential problems and select the best method before entering the operating room. ‘This new approach is greatly relieving
the stress from the surgeons, who can now quietly investigate various solutions without the stress of the patient waiting on the table. ‘This also improves the outcome of
the surgery, helping reduce the recovery g December 2018/January 2019 Scientific Computing World 19
Simulation example made using Comsol Multiphysics software, courtesy of Comsol
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28
