Sim4Life V9.4: Refined by Research and Real-World Applications
Sim4Life V9.4 further strengthens its position as the platform of choice for neurostimulation modeling, with targeted improvements to quality, robustness, and usability driven by demanding real-world application work.
Neurostimulation studies often require more than just electric field mapping. Modern workflows typically involve:
• anatomically detailed personalized models,
• highly resolved low-frequency electromagnetic simulation,
• neuron-level response modeling,
• evaluation of safety-relevant quantities, such as induced tissue heating and charge injection.
Sim4Life integrates these components into a single computational framework, enabling controlled in silico studies that connect image-based modeling, physics, and physiology.
Version 9.4 builds on this foundation. Two recent customized research projects – carried out by Z43 partner the IT'IS Foundation for industrial customers with concrete design, regulatory, and translational needs – illustrate both the platform's capabilities and the type of demanding applications that directly informed the refinements in this release.
Application Showcases
Case Study 1
Personalized tPCS Modeling and Neuronal Response Analysis – IT’IS Foundation in Collaboration with AscenZion
Transcranial pulsed current stimulation (tPCS) is an emerging non-invasive neuromodulation approach that aims to modulate brain function and treat conditions such as cerebral palsy and autism using low-intensity pulsatile currents.
As research progresses, central questions remain:
• How does tPCS interact with neurons in the brain, and why is it effective when transcranial alternating current stimulation (tACS) is not?
• What is required to build a personalized tPCS planning tool – one that accounts for tPCS-specific neural responses and improves treatment effectiveness?
To address this, IT’IS executed a customized research study combining:
• highly detailed, personalized anatomical head models,
• low-frequency electromagnetic simulation including electrode-tissue interface effects,
• neuron-level response modeling across cortical cell types,
• population-level analysis of exposure and response variability.
The results revealed fundamental differences in how tPCS and tACS interact with brain neurons, showing that tPCS effectively polarizes pyramidal neurons in the cortex and modulates cerebellar Purkinje cell firing rates, consistent with observed therapeutic responses. Cross-subject comparison confirmed that variability in skull structure and brain folding significantly affects outcomes, establishing requirements for anatomically personalized treatment planning.
Please visit the deep-dive on sim4life.swiss to learn more.
Case Study 2
In Silico Vagus Nerve Stimulator: Design, Optimization, and Safety Evidence Generation – IT’IS Foundation
Implanted peripheral nerve stimulation requires effective recruitment or blocking of target nerve fibers while ensuring safety. The design space is large: electromagnetic exposure, axonal electrophysiology, tissue heating, and their interactions must all be accounted for. Credible in silico regulatory evidence demands both uncertainty quantification and experimental validation.
Key questions include:
• What stimulation current is required to achieve defined recruitment or conduction blocking levels?
• What temperature rise accompanies those currents?
• Which design parameters result in a superior safety and effectiveness profile?
To address these, IT'IS executed a customized research study for a large medical device manufacturer, combining:
• a multi-fascicular cervical vagus nerve model constructed from segmented histological data, with micrometer-scale features and realistic fiber populations,
• electromagnetic, electrophysiological, and thermal simulations using quality-assured models and tissue properties in Sim4Life,
• parameterized modeling and multi-objective optimization (Model Intelligence Hypertools) to identify superior designs, and
• systematic convergence analysis and surrogate model-based uncertainty quantification (Model Intelligence Hypertools).
The results identified designs with superior safety and effectiveness profiles. Key predictions were confirmed by ex vivo experiments.
Please visit the deep-dive on sim4life.swiss to learn more.
From Application Insight to Platform Refinement
Both studies pushed the platform hard – multi-scale meshing with tens of millions of cells, extensive Python scripting, long simulation campaigns, and complex 3D visualization of results across multiple anatomical models. In the process, they exposed practical friction points: places where stability under heavy workloads, interface consistency, scripting–GUI alignment, and discoverability of tools and workflows could be improved.
Sim4Life V9.4 addresses these directly.
Stability, performance, and quality assurance:
Improved robustness under demanding workloads, smoother handling of large models, clearer feedback during long-running operations, and a faster patch delivery cycle help ensure that complex projects remain stable and reproducible.
A cleaner, more consistent user interface:
Streamlined tool organization reduces visual clutter and improves focus during multi-step simulation workflows.
Integrated AI assistant:
Directly accessible from the search bar, the AI assistant answers questions about tools, workflows, solvers, and APIs, helping users navigate modeling tasks, understand concepts, and locate relevant functionality more efficiently.
Stronger scripting and documentation coherence:
Improved alignment between GUI and Python workflows, a clearer API structure, and more accessible documentation support the kind of large-scale, script-driven studies illustrated above.
Sim4Life V9.4 demonstrates how anatomy, physics, and physiology connect within a single, reproducible in silico environment. For research and development teams working on neurostimulation – whether in transcranial brain stimulation or implanted peripheral nerve interfaces – the platform provides the integration, numerical control, and application-tested robustness needed to move from mechanism to design to regulatory evidence.
Now Available
The fully refined power of Sim4Life V9.4 is available as of today for and has been rolled out for all our cloud versions for commercial users, researchers, and students.
The Sim4Life V9.4 Desktop Installer is available here.
If you are interested in collaborating with our experts on specific studies, contact the IT’IS Customized Research team to explore a research solution for your application.
For further information, please email us at s4l-sales@zmt.swiss or call +41 44 245 9765.
Kind regards,
The Sim4Life Team
At the end of January, Z43 colleagues gathered on Mount Pilatus for a two-day retreat to deepen their understanding of the brain and explore strategies to improve focus and efficiency at work.
From January 26–27, 2026, Z43 colleagues gathered for their annual retreat, titled “The Road to a More Brainy Z43 – Rewiring Focus to Combat Distraction”, to deepen their understanding of the brain and to develop a shared understanding of how mobile phones and other common distractions affect attention and performance in today’s workplace. For this purpose, participants made their way up to Mount Pilatus in central Switzerland with clear views across the snow-covered Alps, and just enough distance from day-to-day routines to think without interruption.
The first part of the retreat focused on building a broad, practical understanding of the science of the brain. Sessions covered the basics of functional brain networks, the role of neuroplasticity in rehabilitation and learning, and its relevance for attention, habits, and addiction. Participants also examined how modern technologies intentionally exploit attention and reward mechanisms, contributing to distraction and reduced focus.
The content was structured around short, book-based presentations and discussions, drawing from a curated selection of literature on behavior, intelligence, neuroplasticity, and attention. These included Behave: The Biology of Humans at Our Best and Worst by Robert Sapolsky, How the Mind Works by Steven Pinker, A Brief History of Intelligence: Evolution, AI, and the Five Breakthroughs That Made Our Brains by Max Bennett, The New Science of Consciousness by Paul L. Nunez, Neuroplasticity by Moheb Costandi, In Search of Memory by Eric R. Kandel, Irresistible by Adam Alter, Dopamine Nation by Anna Lembke, and Stolen Focus by Johann Hari. The discussions were complemented by targeted online research and additional reference material.
The second part of the retreat consisted of three structured brainstorming sessions, in which participants explored how ownership, commitment, and efficiency can be strengthened by actively addressing focus deficits – both at the individual level and across the organization. The retreat thus established a shared language and reference framework for understanding how brain function, attention, and behavior affect everyday work. It also created space for focused discussion on how these insights can inform more deliberate and effective ways of working.
The next step is to take these insights back and translate them into concrete practices, structures, and long-lasting habits that support sustained focus and effective collaboration in daily operations.
Thanks to all participants for maintaining focus over two dense days – despite the altitude, the views, and the traditional cheese fondue in the evening!
Participants of the Zurich43 Retreat 2026
From December 8 – 12, 2025, ZMT and Z43 partner Schmid & Partner Engineering AG (SPEAG) together hosted our Annual Strategic Sales Meeting at our headquarters in Zurich, bringing together our regional sales teams, sales agents, and representatives from around the world to share insights, strategize, and align for future growth.
This year’s theme was success stories, with each agent and representative, as well as Z43 members, sharing examples of how a customer need was met by a hardware, software, support, or service solution – often a combination thereof. A frequent theme was the complexity of the customer’s challenges, with many technical, production or regulatory goals requiring extensions of current methodologies or even novel solutions. ZMT and SPEAG are uniquely capable of meeting these needs with their focus on cutting-edge hardware and software tools, backed by the latest research and regulatory science. These stories also highlighted that customers become confident in using these powerful tools correctly thanks to the strong scientific and technical support offered with our products. Lost opportunities were also discussed with an eye towards continuous improvement of both products and sales, and the product roadmaps for 2026 were presented by Z43’s product heads.
On Monday evening, the guests enjoyed a seasonal traditional fondue dinner under a transparent globe overlooking the Zurich Opera House, the city lights, and the nearby Christmas market. They were then surprised by a rare private performance from a traditional Zäuerli group from the Kanton Appenzell Ausserrhoden, who scare away bad spirits with their bells and bring good cheer with their traditional distinctive style of ‘natural’ yodeling. Check out the video here!
A big thank you to everyone involved for a very productive week!
The IT’IS Foundation proudly announced the release of six new Virtual Population (ViP) models with advanced posing capabilities — and fully compatible with Sim4Life. The improvements include more realistic deformations in extreme postures –such as arms raised overhead – and additional spinal joints that enable natural neck and back bending.
These upgrades increase anatomical realism and provide greater application-specific flexibility, making them particularly valuable for simulations in areas like magnetic resonance safety assessments and wireless power transfer. The added spinal joints allow postures to be adapted more precisely to a variety of use cases.
This release marks the beginning of a phased upgrade of the entire ViP library, with more models to follow soon. All upgraded models remain fully compatible with Sim4Life and continue to adhere to ViP quality standards.
Sim4Life.web V9.2: The Beginning of Modeling Intelligence
Sim4Life.web V9.2 debuts Modeling Intelligence, marking the start of a powerful toolset that turns simulation data into actionable insights.
Its upgraded multi-objective optimizer enables engineers and scientists to visualize competing goals—for example, safety limits, therapeutic efficacy, and power efficiency—through interactive Pareto plots for a wide range of applications, including deep brain and cardiac stimulation, magnetic resonance imaging (MRI) coil design, and implant antennas.
This is demonstrated in a recent spinal cord stimulation study resulting in an optimized pulse shape that achieved the same recruitment using 5× less energy—boosting implant longevity and safety. Take a deep dive and read more here.
Beyond optimization, V9.2 accelerates your daily work with:
- Artificial intelligence (AI)-driven segmentation and meshing for trunk (new) and head regions, with a 2× speedup,
- a new OpenFOAM plugin for one-click fluid flow and structural mechanics simulations in Sim4Life,
- numerous refinements across solvers, developer tools, and usability.
What’s New & Why It Matters
Modeling Intelligence — Turning Trade-Offs into Design Insights
The upgraded optimizer in Modeling Intelligence combines advanced surrogate modeling with a multi-objective genetic algorithm (MOGA) to turn demanding parameter sweeps into interactive, data-driven explorations.
It visualizes Pareto fronts that illustrate how, e.g., safety, efficacy, and energy efficiency interact, helping users identify the right design solution for their application.
In a recent spinal cord stimulation study, this workflow uncovered pulse shapes that achieve equal recruitment with up to 5× lower energy use, demonstrating how Modeling Intelligence can directly improve device longevity and safety margins.
In Sim4Life.web V9.2, users can take Sim4Life’s advanced modeling and simulation setups to the next stage – exploring large parameter spaces and leveraging advanced surrogate modeling techniques for interactive, informed design decision-making. Learn in this Deep Dive how the Multi-Objective Genetic Algorithm (MOGA) Optimizer was utilized to optimize stimulation pulses for spinal cord injury neurorehabilitation, maximizing efficacy while minimizing energy consumption - thereby advancing patient safety and implant longevity.
Quicker Setup of Personalized Models
Our third-generation deep learning model labels head, neck or torso tissues directly from magnetic resonance imaging (MRI)/computed tomography (CT) scans and automatically pre-meshes them, reducing most neuro-stimulation projects from raw images to a “solver-ready” state in about half the clicks and minutes** compared to earlier versions.
In Sim4Life.web V9.2, users can apply AI-powered segmentation to medical images (either MRI or CT) of the entire trunk region and quickly generate corresponding 3D models without the need for manual segmentation. The tool can segment all major internal organs, vertebrae, and other bones, as well as several individual arteries, veins, and muscles. Upon assigning tissue properties, the models are ready for simulations.
Click‑to‑Install OpenFOAM Plugin
OpenFOAM’s industry-standard solvers now launch straight from Sim4Life’s Plugin Manager: import your meshed anatomy, choose a fluid- or small-strain-mechanics solver, set boundary conditions, and press “Run”. All dictionaries, solver logs, and post-processing views are stored within the Sim4Life project, ensuring that studies are fully reproducible and shareable—requiring no command-line tools, no external dependencies, and preventing broken links.
Using Sim4Life.web V9.2, a 500 kHz transcranial focused ultrasound device is modeled to target the left hippocampus of Duke’s (Virtual Population) head, with CT-based maps capturing skull heterogeneity. PEGylated thermosensitive liposomes (100 nm) loaded with doxorubicin circulate in the vasculature. Focused ultrasound induces pressure-dependent release, described in OpenFOAM as a convection–reaction–diffusion process with subsequent drug diffusion into brain tissue. The coupled workflow in Sim4Life integrates acoustic propagation, vascular transport, and drug kinetics, enabling the joint simulation of liposome and drug concentration dynamics.
Broadband Skin Power Absorption Model – mmWave Compliance
Sim4Life.web V9.2 offers a highly efficient implementation of the latest broadband skin model, recently published [Christ et al. (2025)] and adopted in the latest draft of the IEC/IEEE TR APD and other upcoming national regulations. It enables determination of absorbed power density for any device operating at frequencies between 10 and 110 GHz, across all use cases and human models.
Sim4Life.web V9.2 was used to simulate a 28 GHz smartphone antenna in close proximity to a SPEAG Absorbed Power Density (APD) phantom, using the new Human Skin (Coated, mmWave) model. The visualization highlights the realistic interaction of the antenna’s near-field with the coated-skin formulation, showing the spatial distribution of absorbed power density across the phantom surface. The example illustrates how the model captures reflection and absorption at the air/skin interface, enabling accurate and efficient compliance and performance assessments without explicit meshing of the thin-film coating.
Expanded Libraries & Templates
Sim4Life.web V9.2 introduces a deep brain stimulation (DBS)/stereoelectroencephalography (sEEG) electrode generator, a wizard for the rapid creation of parameterized implants used in these technologies. Electrode geometry—including diameter, contact length, spacing, arc angle, segmentation, and tip offset—can be customized interactively or scripted via the Python-based application programming interface. This streamlines the setup of stimulation and recording electrodes, supporting applications from DBS therapy planning to implant safety assessments. By reducing manual modeling effort, the new tool shortens setup time and enhances reproducibility across neurostimulation and implant safety studies.
In Sim4Life.web V9.2, our library of templates now includes two new tools for accelerating electrode development, DBS/sEEG and paddle electrode generators—which allow users to generate designs in just a few clicks, with all aspects of the geometry fully parametrized.
Hands-On Help, When You Need It
In Sim4Life.web V9.2, the integrated Help Center allows users to easily connect with Application Support and share logs and screenshots (opt-in) to accelerate troubleshooting. This streamlined communication makes it easier to get support when needed and helps new users get onboarded more quickly and confidently.
Now accessible via our Help Center in Sim4Life.web V9.2, users can start a chat with our Support Team for live assistance with simulations. During the chat, directly share projects with a single click or book a call for more tailored assistance or general training sessions.
**Benchmark figures reflect typical in-house test cases; actual gains depend on model size and solver settings.
Choose Your Path
| You are... | Next Step |
| Medical Device R&D | Book a private Onboarding session |
| Academic / Student | Activate Sim4Life.science free cloud credit |
| Plugin Developer | Get the SDK & join the community |
Sim4Life.web V9.2 is now available and has been rolled out on all our cloud platforms for commercial users, academics, and students.
For further information, please email us at s4l-sales@zmt.swiss or call +41 44 245 9765.
Kind regards,
The Sim4Life Team
Z43 and DYMSTEC welcomed over 100 participants from academia, industry, and governmental agencies to their annual joint workshop in Seoul, South Korea, on September 18, 2025.
On September 18, 2025, Z43 and DYMSTEC welcomed over 100 participants from academia, industry, and governmental agencies to their annual joint workshop in Seoul, South Korea. This year’s event, hosted at the Gachon Convention Center in Sungnam-si, Gyeonggi-do, once again served as a hub for knowledge sharing, networking, and showcasing Z43’s latest technological innovations.
Unlike the workshops of previous years that featured multiple parallel tracks, this year’s workshop centered on a single, focused program. The morning sessions were concentrated on the wireless industry, highlighting the latest developments in measurement and compliance solutions, while the afternoon sessions shifted to medical and life-sciences applications, showcasing advances in simulation and neurostimulation research. This streamlined format enabled participants to become immersed in both fields through in-depth presentations and live demonstrations, all during one intensive and inspiring day.
ZMT showcased the recently released Sim4Life V9.0, a universal tool for computational life and health sciences. With full o²S²PARC integration, a plugin framework for third-party solvers, artificial intelligence (AI-) driven anatomical modeling, and new “Hypertools” to address, e.g., response surfaces and uncertainty quantification. Participants were also treated to a sneak preview of Sim4Life.web V9.2, due for release in early October, which introduces a multi-objective optimizer with live Pareto plots, full OpenFOAM integration, next-generation AI segmentation, and additional features – all designed to make simulations more efficient, powerful, and accessible. To further support users, Sim4Life.web V9.2 will also feature integrated interactive chat/support tools for direct assistance and faster troubleshooting.
SPEAG provided comprehensive updates on its latest innovations in measurement and simulation technologies. Attendees learned about several enhanced modules of the DASY8 platform, including the upcoming updates for testing proximity sensors with Module SENS V1.10, the updated DASY8/6 Module WPT V3.0 for characterization and compliance testing of inductive wireless power transfer (WPT) systems, and the soon-to-be-released DASY8/6 Module mmWave V4.0 and Module APD V2.0 for assessing incident and absorbed power densities from millimeter wave transmitters. The new DAK-R for precision low-loss material characterization was featured, alongside demonstrations of MAGPy3 V3.0 for in situ low-frequency magnetic field exposure assessment, as well as SPEAG’s latest generation of OTA phantoms for over-the-air (OTA) performance, including novel phantoms for proximity sensor testing.
TI Solutions AG presented the latest version of its Temporal Interference Brain Stimulator for Research (TIBS-R V3.2), now compatible with 3T and soon 7T magnetic resonance imaging (MRI) scanners, as well as the new temporal interference (TI) planning tool, TIP V4.0, developed by the IT’IS Foundation. A preview of the upcoming TIBS-R HOME V1.0 system, a portable closed-loop TI stimulation device designed for clinical and home use, sparked particular interest among attendees.
Lively discussions, hands-on product demonstrations, and casual networking over coffee rounded off the event. According to tradition, the day ended with the much-anticipated raffle featuring iconic Swiss gifts, including a gold bar, an exclusive special edition Snoopy MoonSwatch, Freitag bags, Swiss tools, and, of course, delectable Swiss chocolate.
A warm THANK YOU goes out to the DYMSTEC team, led by CEO Peter Song, for once again orchestrating a highly successful and engaging event. Together, Z43 and DYMSTEC continue to foster innovation and collaboration across Korea’s key wireless and medical technology players.
Dymstec CEO Peter Song delivering his welcome speech at the workshop in Seoul to kick off the event.
Dr. Nik Chavannes presenting Z43's opening address at the 2025 Korea workshop.
Dr. Sven Kuehn sharing the latest updates on MAGPy3 / DASY8/6 Module WPT V3.x with the workshop participants.
At an exhibit at the back of the venue, attendees had the opportunity to explore the latest products firsthand and enjoy live demonstrations during the breaks.
Dr. Sylvain Reboux outlining the latest advances of Sim4Life V9.0 and V9.2 and ZMT’s cloud-native simulation platform Sim4Life.web during the "Medical Industry" session in the afternoon
MSc Susana Castanheira handing over a “good amount” of delicious Toblerone chocolate to a lucky raffle winner.
“Mission Accomplished!” – a big THANK YOU to the entire Dymstec team for pulling off another outstanding workshop this year.
Congratulations to the IT’IS Foundation! The newly released versions of the neuro-functionalized Virtual Population (ViP) models, Yoon-sun V4.1 and Jeduk V4.1, are now available to Sim4Life users. These next-gen phantoms provide more than 2,200 individual nerve trajectories and a dedicated spinal canal label, supporting high-resolution simulation of full-body neurostimulation. Both models remain fully compatible with Sim4Life NEURO.
These releases allow researchers to compare male and female model outputs, optimize implant positioning, and validate safety scenarios with unprecedented anatomical detail.
Find more about the release and accompanying media on the IT’IS website. A big thank-you to the team for this outstanding achievement!
IT’IS has expanded its Virtual Population (ViP) library with two new obese models, based on the male phantom Eddie V3.2. Using a validated morphing technique, the models were modified to represent body mass indices of 39 kg/m² and 46 kg/m², respectively. The deformation strategy ensures biological plausibility by increasing adipose and muscular tissue while preserving internal anatomical structures.
These additions expand demographic coverage, enable more comprehensive evaluations – such as magnetic resonance imaging safety assessments – for larger body types. Both models adhere to the stringent ViP quality standards and are fully compatible with the Sim4Life simulation and posing framework.
To obtain a ViP license for Sim4Life, contact us at info@zmt.swiss.
ZMT’s partner organization, the IT’IS Foundation, announces the release of its Tissue Properties Database V5.0.
This update introduces water content data – a crucial parameter for accurate thermal modeling – for all major tissues. The new data will enable an update to tissue-specific thermal properties in an upcoming release of the database.
Additionally, the IT’IS Virtual Population team corrected an underestimated blood perfusion constant for lung tissue, which previously excluded pulmonary blood flow. Many thanks to the vigilant Sim4Life user who identified and reported this issue and helped to resolve it!
This new version of the Tissue Properties Database – already included in the latest version Sim4Life V9.0 – offers users enhanced precision and reliability in their modeling results.
Sim4Life.lite Student Competition 2025
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Enter the Sim4Life Student Competition and win one of our exciting prizes! This year’s Sim4Life Student Competition gives us an opportunity to recognize outstanding work in numerical simulations in a variety of research areas. Students are encouraged to enter the competition by submitting original simulation projects developed with Sim4Life.
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| Who can participate? |
Bachelor’s, Master’s, and PhD students |
| How to participate? |
Each participant must:
Successful submission of a project will be confirmed by email. |
| Evaluation criteria |
The submitted projects will be evaluated by a panel of experts according to the following criteria:
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| Winners |
The winners will be notified individually via email between 1 and 15 of December 2025, and prizes will be officially announced by ZMT thereafter. |
| Awards | 1st Prize USD 3,000 2nd Prize USD 2,000 3rd Prize USD 1,000 |
If you have any questions, please contact the Sim4Life Team at s4l-support@zmt.swiss.
Your Sim4Life Team