Catadioptric Stereo Tracking for Three Dimensional Shape Measurement of MRI Guided Catheters.

The recent introduction of Magnetic Resonance Imaging (MRI)-actuated steerable catheters lays the ground work for increasing the efficacy of cardiac catheter procedures. The MRI, while capable of imaging the catheter for tracking and control, does not fulfill all of the needs required to identify and develop a complete catheter model. Specifially, the frequency response of the catheter must be identified to ensure stable control of the catheter system. This requires a higher frequency imaging than the MRI can achieve. This work uses a catadioptric stereo camera system consisting of a mirror and a single camera in order to track a MRI actuated catheter inside a MRI machine. The catadioptric system works in parallel to the MRI and is capable of recording the catheter at 60 fps for post processing. The accuracy of the catadioptric system is verified in imaging conditions that would be found inside the MRI. The stereo camera is then used to track a catheter as it is actuated inside the MRI.