Behind The Scenes of Medical Device Development

If you’ve ever gotten a vaccination or given blood, you’ve been on the receiving end of one of the world’s most widely used medical devices: the syringe. Billions of syringe injections are given worldwide each year, so you can imagine the importance of producing these high-volume disposable products in a way that ensures they function safely and effectively.

Computational modeling and simulation is one way syringe and other medical device manufacturers can meet the need for reliably safe and effective products. Computational modeling and simulation is a virtual way of evaluating product performance, manufacturability and robustness. Through this approach, manufacturers can virtually verify and validate new design concepts. For example, a medical device manufacturer can use:

• Injection molding simulation to explore how plastic flows when it is injected into high-volume molds; based on the simulation, the manufacturer can then determine not only the ease of manufacturing a given design but also the likely quality of the manufactured part.
• Structural analysis or finite element analysis (FEA) to simulate the intended use of a product, or its misuse, and ensure a part will have the desired functionality and structural integrity. This type of simulation can include the effects of nonlinear materials, large deformations, fracture and damage, and contact between multiple components.
• Computational fluid dynamics to predict fluid flow through products and the human body for optimal drug delivery.  

BD, a medical device manufacturer, recently used computational modeling and simulation in their efforts to help tackle a global public health concern: the spread of disease through the reuse of syringes. The goal was to develop a reuse-prevention syringe, that is, a syringe with a “passive disabling system” that would make it unusable after a single use. The product development team evaluated hundreds of virtual design iterations. Based on these simulations, they found that the optimal design had a low activation force, where the plunger of the syringe was easily pressed to deliver medication. At the same time, the syringe had a high disengagement force, where the plunger could not be easily retracted without disabling it in order to prevent reuse. BD products housing this reuse prevention mechanism have been successfully launched worldwide with significant user acceptance and reduced development time and cost.

As the above examples show, computational modeling and simulation has an important role to play in medical device development. The ASME Verification and Validation (V&V) 40 Committee in Computational Modeling of Medical Devices is working to foster that role by developing a standard for quantifying the accuracy and credibility of computational models and simulations. The standard, called ASME V&V 40, will help medical device manufacturers generate credible digital evidence that verifies and validates the designs they submit for approval to regulatory agencies such as the U.S. Food and Drug Administration (FDA). The purpose of using computational simulation and modeling as “regulatory-grade” evidence is to minimize the reliance on other forms of evidence, including physical bench testing, preclinical animal testing, and human clinical trials. Given the active participation of the medical industry, software developers and the FDA in ASME’s efforts, computational modeling and simulation promises to become an increasingly significant part of the product development and regulatory process.