PURPOSE-To assess the feasibility of the use of preprocedural imaging for guide wire, catheter, and needle navigation with electromagnetic tracking in phantom and animal models.
MATERIALS AND METHODS-An image-guided intervention software system was developedbased on open-source software components. Catheters, needles, and guide wires were constructed with small position and orientation sensors in the tips. A tetrahedral-shaped weak electromagnetic field generator was placed in proximity to an abdominal vascular phantom or three pigs on the angiography table. Preprocedural computed tomographic (CT) images of the phantom or pig were loaded into custom-developed tracking, registration, navigation, and rendering software. Devices were manipulated within the phantom or pig with guidance from the previously acquired CT scan and simultaneous real-time angiography. Navigation within positron emission tomography (PET) and magnetic resonance (MR) volumetric datasets was also performed. External and endovascular fiducials were used for registration in the phantom, and registration error and tracking error were estimated.
RESULTS-The CT scan position of the devices within phantoms and pigs was accurately determined during angiography and biopsy procedures, with manageable error for some applications. Preprocedural CT depicted the anatomy in the region of the devices with real-time position updating and minimal registration error and tracking error (<5 mm). PET can also be used with this system to guide percutaneous biopsies to the most metabolically active region of a tumor.CONCLUSIONS-Previously acquired CT, MR, or PET data can be accurately codisplayed during procedures with reconstructed imaging based on the position and orientation of catheters, guide wires, or needles. Multimodality interventions are feasible by allowing the real-time updated display of previously acquired functional or morphologic imaging during angiography, biopsy, and ablation.Address correspondence to B.J.W.; E-mail: bwood@nih.gov. B.J.W. and K.C. are coinventors on related US Patent Application #10/377,528, "Interstitial Magnetic Position Sensor System and Needle for Surgical and Image-guided Therapy Navigation." B.J.W. and N.G. are coinventors on US Patent Application: "Design for Guiding and Electromagnetic Tracking of Radiofrequency Ablation Needle" (US Provisional Patent Application # 60/625,186). Philips owns intellectual property and has market interest in this area. J.K., J.B., and S.K. are salaried employees of Philips Electronics. The mention of commercial devices or products, their source, or their use in connection with material reported herein is not to be construed as either an actual or implied endorsement of such products by the National Institutes of Health, the Department of Health and Human Services, or the Public Health Service. N.G. is President and a major shareholder of Traxtal, Inc. DEVICE navigation in angiography and interventional radiology has traditionally relied on real-time imaging to monitor anatomic position...
