Steerable Needle Conor James Walsh - Grand Challenge Stories

Conor James WalshOpportunity:Thermal ablation is an emerging cancer therapy that is substantially cheaper and less invasivethan other methods because it uses localized heat to destroy tumor. However, applying heat toa specific location is difficult because of non-uniform heat transfer from an electrode. Thisimprecision frequently results in a failure to destroy a tumor or damage to healthy tissue(Figure 5).Figure 5: On the left, the small burn volume associated with a single radiofrequency ablation probe is shown.While the temperature at the tip is 100 C (cannot exceed this because boiling occurs), it drops off rapidly andthus does not destroy the entire tumor. On the right a larger spherical ablation volume is shown that is generatedwith a multi-probe electrode; however this results in a large amount of damage to healthy tissue.Invention:To address this limitation, I conceived the idea to steer an electrode tip to burn multiple pointsin a tumor and then conceptualized, designed and built the first robot capable of achievingthis 1 .Figure 6: The concept of robotically steering a radiofrequency ablation probe is shown by the three adjacent burnvolumes labeled 1,2 and 3. With smaller burn volumes, much faster and more effective destruction of the tumorcan be achieved without the need to damage the surrounding healthy tissue.1 Walsh, C., Franklin, J., Slocum, A., Guerrero, J., Gupta, R. Image-guided Telerobot for Percutaneous DistalTip Repositioning, IEEE Transactions on Robotics, (in preparation).