By Matthew Stock
A prototype surgical tool that combines preoperative CT data with state-of-the-art sensing technology could put the ability to carry out complex operations in the hands of many more doctors, according to its developers.
The hand-held device, called Chimaera, could revolutionize the delivery of miniaturized neurostimulators to specific nerves, and give many more patients access to pioneering new pain management technology.
Different regions of the brain are known to be linked to areas of perception, such as pain. Neurostimulation involves applying an electric impulses to nerves to alter brain activity in a specific area.
"Pain is simply a series of electrical signals as transmitted through the nervous system, whether that's pain from a broken leg or pain from a headache. So by putting an electrical signal directly into target nerves - in a known way, you need to understand the waveforms to put into that nerve - you're able to lessen, override or deliver particular signals which influences how your brain is experiencing things," explained Simon Karger from technology developers Cambridge Consultants.
The main challenge with neurostimulation procedures is safely accessing the correct nerve - which might be deep in the face or behind an eye-socket - and implanting the device without complications for the patient.
Chimaera is designed to make implanting neuromodulators to nerves much easier by integrating surgical, sensing and implant delivery functions in one intelligent device. It uses preoperative CT (computerized tomography) scan data to create a 3D X-ray image of the patient, enabling surgeons to identify critical structures, such as nerves and blood vessels. This combines with the intraoperative data from Chimaera's sensing technology to guide the surgeon to the precise location of a procedure, helping to ensure the surgical device stays on a predetermined safe pathway.
The real-time data generation is designed to be used in conjunction with optical wearable technology, such as Google glass. This means a surgeon can literally 'see' exactly where they are within the body at any point during an operation. Once the target nerve has been reached the sensors also let the surgeon know, and the implant can then be deployed down the device.
Karger said their aim was to figure out how neuromodulators - measuring less than a centimeter in length - could be implanted as simply and quickly as possible. Chimaera, he said, could allow doctors around the world perform a procedure that can currently only be carried out by a handful of people.
"With Chimaera, what we've done is we've combined smart sensing technology, pre-operative planning, we've taken small implant form-factors; and we've combined both implant delivery with surgical tool to provide a completely connected, unified surgical system that has the potential to take a surgery that maybe only four or five people in the world can carry out today and make it accessible to a broad cross-section of general surgeons. By doing that we make it accessible to a much, much broader patient population," he said.
The developers said that while most of today's surgical tools are largely passive, offering surgeons little feedback, Chimaera opens the door to a new generation of neurostimulation implant procedures. It could, they say, enable more surgeons to carry out complex operations at lower risk and with better results for patients.
While it may be some time before a device like Chimaera is in surgeons' hands, Karger said it could pave the way for wireless pain management for patients using, for example, their mobile phone: "Imagine a migraine sufferer who literally as they feel the onset of their migraine, can reach for their cell phone and dial-down the pain. That is a life-changing therapy for that patient. And crucially what it does is it changes that patient from a patient into a consumer; they don't need to feel like a patient anymore."
Developers Cambridge Consultants say Chimaera is the equivalent of a 'concept car' that demonstrates their vision for the next generation of surgery. They say that all of the technologies that are used in Chimaera currently exist, and they are now looking for partners to lead a product development cycle to turn it into a medical device ready for market.