19F MR Imaging Golden Angle-based Capsule Tracking for Intestinal Transit and Catheter Tracking: Initial in Vivo Experience

Purpose: To combine fluorine 19 (F-19) magnetic resonance (MR) imaging and golden angle radial acquisition and to assess the feasibility of F-19 MR imaging golden angle-based tracking for catheter tracking applications and simultaneous three-dimensional (3D) intestinal tracking of ingested F-19-labeled capsules in vivo. Materials and Methods: Approval from the local ethical committee and informed consent from the subject were obtained. In vitro studies were performed to assess F-19 MR imaging golden angle-based tracking reliability with regard to temporal resolution and different tracking strategies (boundary condition-free tracking, composite image-based tracking, and model-based tracking). In vivo performance of the method was investigated in one healthy volunteer on 2 days. On study day 1, a duodenal catheter incorporating five F-19-labeled capsules was administered nasally, and its 3D movement was tracked inside the stomach and esophagus. On study day 2, three F-19-labeled capsules were swallowed, and intestinal movement was tracked. Results: Simultaneous in vivo 3D tracking of multiple F-19-labeled capsules was successfully performed without incorporation of boundary conditions at a temporal resolution of 252 msec. Incorporation of boundary conditions with composite image-based tracking and model-based tracking increased tracking reliability and enabled temporal resolution as high as 108 msec. Conclusion: Use of F-19 MR imaging golden angle-based capsule tracking enables in vivo tracking of F-19-labeled capsules and catheters at high temporal resolution. The presented method is applicable to physioanatomic studies of the gastrointestinal tract and shows potential for real-time tracking in interventional radiology. (C) RSNA, 2012