BACKGROUND: It is tedious and difficult to position a flexible catheter in a target vessel branch within complicated-shaped vessels owing to the lack of real-time visual feedback. Digital subtraction angiography and fluoroscopic guidance are currently used for catheter placement. METHODS: The proposed method employs an electromagnetic (EM) tracking system to track a sensor-attached catheter. Vessel centerlines are extracted from the CT angiography image, based on which a navigational information tree is built to facilitate catheter manipulation. A virtual endoscopy technique is adopted to generate virtual intravascular video as visual feedback. Unscented Kalman filtering based image registration is performed to align the EM tracker frame with the anatomical atlas and to envision the target registration error. RESULTS: Preliminary experimental results showed the feasibility and effectiveness of the new method, with navigation accuracy of 1.80 ± 0.85 mm. CONCLUSIONS: The proposed method can provide continuous virtual visual feedback to facilitate catheter placement and has the potential for clinical use, with significant reduction in X-ray radiation exposure and doses of contrast agents.
BACKGROUND: It is tedious and difficult to position a flexible catheter in a target vessel branch within complicated-shaped vessels owing to the lack of real-time visual feedback. Digital subtraction angiography and fluoroscopic guidance are currently used for catheter placement. METHODS: The proposed method employs an electromagnetic (EM) tracking system to track a sensor-attached catheter. Vessel centerlines are extracted from the CT angiography image, based on which a navigational information tree is built to facilitate catheter manipulation. A virtual endoscopy technique is adopted to generate virtual intravascular video as visual feedback. Unscented Kalman filtering based image registration is performed to align the EM tracker frame with the anatomical atlas and to envision the target registration error. RESULTS: Preliminary experimental results showed the feasibility and effectiveness of the new method, with navigation accuracy of 1.80 ± 0.85 mm. CONCLUSIONS: The proposed method can provide continuous virtual visual feedback to facilitate catheter placement and has the potential for clinical use, with significant reduction in X-ray radiation exposure and doses of contrast agents.