From Physics-Based Simulation to Surgical Robots| Show Me The Evidence E8- Dr Dwight Meglan

Show Me the Evidence, Episode 8 Guest: Dr Dwight Meglan Topic: Physics-Based Simulation, Surgical Robotics and Why Simulators Still Don't Measure What Matters Episode Summary In this episode, Professor Tony Gallagher is joined by Dr Dwight Meglan, the engineer who developed one of the first physics-based virtual reality simulators for endovascular procedures in the late 1990s, and who has spent the last two decades building surgical robots. Together they trace 30 years of simulation-based training and ask why so little has changed: simulators are still not verified against real-world physics, the field still measures process rather than skill, and device manufacturers, not educators, still set the agenda. The conversation ranges from haptics and instrumented torquers to Likert scales, credentialing committees, telesurgery risk, and why autonomous surgical robots are a regulatory and financial impossibility rather than a technical one. It closes with the evidence for Proficiency-Based Progression (PBP) and the leadership needed to adopt it. Key Topics Covered 1. Building the first physics-based VR simulators | 0:00 Meeting at Medicine Meets Virtual Reality in the late 1990s Real-time physics of tool and tissue interaction, fluoroscopy and haptic feedback Why the goal was to replicate reality, not design a user experience Physics tests to verify simulator correctness still do not exist, 25 years on 2. Who really drives simulation: the device manufacturers | 2:24 Manufacturers pay for simulation, so manufacturers shape it Training to use the device versus training to perform the procedure Simulators in exhibition booths: marketing tools first, training tools second 3. Haptics and the sensory threshold problem | 3:55 The instrumented torquer: measuring what cardiologists actually feel Just noticeable difference thresholds vary between clinicians Still no published datasets on the forces a cardiologist feels during catheterisation Clinicians praising the haptics on simulators where the haptics were switched off 4. Using devices safely: the stapler and the defibrillator | 8:52 A stapling device with a 6 to 27 per cent leak rate, where one third of patients who develop a leak die Training to the instructions for use is device safety training, not surgical skills training Cardiac defibrillator implantation: clinicians departing from the instructions for use Construct validity findings: some very senior clinicians perform worse than the worst trainee when assessed with objective, peer-derived metrics 5. What should a simulator measure? | 13:19 The original approach: record everything, then find the measures that matter Metrics for mechanical thrombectomy for acute stroke, developed from the human procedure with Mentice How clinician-led metrics forced a redesign of contrast injection, later patented It works when you insist on it, but you must start with the metrics 6. The state of simulation metrics today | 17:35 At a recent conference, almost none of the exhibited simulators had any metrics at all Some manufacturers avoid measurement deliberately: plausible deniability Validated metrics as a purchasing condition: if you cannot build them in, we will not buy 7. From simulation to surgical robotics | 21:52 Why simulation felt like a capped market and robotics did not The analogous DNA of simulators and robots as real-time information processing systems Verification versus validation: robots are bench-tested against dozens of specifications, simulators almost never are 8. Measuring process, not skill | 26:49 Motion tracking and path length: lessons not learned from laparoscopic surgery AI-driven pattern hunting as a fishing expedition without a hypothesis Suturing as the test case: the physics of tissue apposition has never been published Physical intelligence and humanoid robotics will improve simulation from the outside in 9. Likert scales are not measurement | 36:47 Binary, procedure-specific metrics require scoring the entire video, reliably, in pairs One-to-five ratings after watching a few minutes of video are hand waving, not assessment Ring exercises on robotic simulators have never been verified against real forces 10. Whose job is it? Credentialing and privileging | 39:27 Manufacturers certify device use; professional societies and hospitals grant privileges Per-procedure privileging in the United States versus broad qualification in Europe The credentialing committee problem: standards set by the least experienced member Case volume, fellowship length and reputation are social proof, not evidence of competence 11. A jumbo jet a day: the human cost | 44:43 Deaths from surgical skills deficits estimated as equivalent to a full jumbo jet crashing every day, consistent with evidence that around 4.2 million people die within 30 days of surgery each year (Nepogodiev et al., The Lancet, 2019) Why one death at a time never makes headlines the way one crash does The Bristol Royal Infirmary case: peers knew for a decade before the front pages forced action (The Bristol Royal Infirmary Inquiry, Kennedy Report, 2001) Telesurgery at scale: how one underperforming surgeon could soon harm many patients quickly 12. The PBP evidence and the leadership gap | 47:47 Systematic review and meta-analysis evidence: PBP-trained clinicians make approximately 60 per cent fewer objectively assessed intraoperative errors Training to proficiency in one third of the time and at less than half the cost of conventional training "A failure of leadership": adoption at ORSI Academy, AANA, ERUS under Alberto Breda, and increasingly Medtronic cardiovascular came from senior leaders making it non-negotiable The aviation lesson: flight simulation was mandated by government before the evidence existed, while surgery has the evidence and no mandate Publication: Mazzone, E., Puliatti, S., Amato, M., Bunting, B., Rocco, B., Montorsi, F., Mottrie, A. and Gallagher, A.G. (2021). A Systematic Review and Meta-analysis on the Impact of Proficiency-based Progression Simulation Training on Performance Outcomes. Annals of Surgery, 274(2), 281-289. DOI: 10.1097/SLA.0000000000004650 Publication: Puliatti, S., Rodriguez Peñaranda, N., Amato, M., De Groote, R., Farinha, R., Bunting, B., van Cleynenbreugel, B., Mottrie, A. and Gallagher, A.G. (2026). Randomised trial on the economic impact of proficiency-based progression vs conventional robotic surgical training. BJU International, 137, 493-501. https://doi.org/10.1111/bju.70130 13. The next 10 years: AI, automation and the autonomy myth | 54:08 AI will lower the barrier to building simulators and add semi-automated instruction Part-task automation, such as a supervised stapler, is plausible; autonomous procedures are not The barrier is financial and regulatory: manufacturers will not accept liability for practising medicine The self-driving analogy: millions of hours of verified synthetic data would ...