By Crystal Mackay, MA'05
It’s an uncommon surgery – one that involves using a surgical microscope to very precisely cut into, and then repair the lining that covers the spinal cord. Of more than 1,500 surgeries they will experience during their residency, most neurosurgery residents will only perform about a dozen or so of these spinal dural repairs throughout their entire training.
So how can they become efficient, competent and confident performing this delicate surgical technique before they complete their residency training?
Dr. Jonathan Lau, a neurosurgery resident now working on his PhD, found himself asking this exact question during his training. Teaming up with Terry Peters, PhD, Elvis Chen, PhD, and the Virtual Augmentation and Simulation for Surgery and Therapy Lab at Robarts Research Institute, Dr. Lau has developed a surgical simulation training tool that mimics what a surgeon would see, feel and experience during one of these procedures.
“The old school thinking around surgery training is to ‘see one, do one, teach one,’” Chen said. “Now we’ve developed fairly sophisticated models that residents can use outside of the OR, to both train and then assess how well they’ve done.”
The simulator, currently being integrated into the neurosurgery curriculum at Schulich Medicine & Dentistry, uses a combination of 3D printing to mimic the spine, synthetic materials to recreate the fat and tissue, and a water pump to provide a realistic experience of the pulsating spinal fluid inside the spinal covering, called the dura.
The simulator recreates the dura with the pericardium from a pig. Water inside the pump also allows surgeons-in-training to experience the actual haptics of the surgery and also to be sure that their repair is water-tight and not leaking. The simulator is part of the Drake-Hunterian Surgical Skills Laboratory, managed by Dr. Stephen Lownie and Lynn Denning, a training facility equipped with a surgical microscope and microsurgical instruments.
“Beyond developing competency, once you have this framework, you can also look at ways in which to improve the procedure. You now have a way of testing all these things without performing the procedure on a patient,” said Dr. Lau, predicting how it can also be used to enable surgeons to develop new more minimally invasive techniques to remove tumors inside the dura or repair a tear.
The other benefit of surgical simulators like this one, is that it allows the surgeon to practise a specific patient-case in a realistic manner before entering the OR. The lab can use CT images to make an exact 3D-printed replica of the patient’s spine, so that if there is an anomaly or a difficult aspect to that specific surgery, they can hone their technique on the simulator before they ever pick up a scalpel.
The simulator won best resident poster prize from the Canadian Neurosurgical Society at the CNSF Congress this past year.
This is just the latest tool to be developed and commercialized in the lab at Robarts. Through a newly formed company called, Archetype Medical Inc., Peters, Chen and company president John Moore, have created similar heart and kidney phantoms that are now being used worldwide.
The advent of 3D printing has been instrumental in moving this new type of simulation forward. Peters says there was a time when it seemed computer simulation would be the way of the future, but the lack of haptic feedback was a barrier to its success.
“With the advent of 3D printing, it’s become clear that replicating the look and feel that you can really touch is really important, and not through a stick that’s attached to a computer,” Peters said. “With the type of simulator we are creating now, you are actually using the instruments that the surgeons would use in the operating room on these physical phantoms that really look and feel like a real one.”
Much like the spinal dural simulator, the imaging fabrication lab's heart phantom has a working heart valve that mimics what a surgeon would experience during a mitral valve repair. This simulator has been commercialized and sold for use around the world including to Harvard Medical School and University College London in the UK.