An MR-Based Model for Cardio-Respiratory Motion Compensation of Overlays in X-Ray Fluoroscopy

Abstract

In X-ray fluoroscopy, static overlays are used to visualize soft tissue. We propose a system for cardiac and respiratory motion compensation of these overlays. It consists of a 3-D motion model created from real-time MR imaging. Multiple sagittal slices are acquired and retrospectively stacked to consistent 3-D volumes. Slice stacking considers cardiac information derived from the ECG and respiratory information extracted from the images. Additionally, temporal smoothness of the stacking is enhanced. Motion is estimated from the MR volumes using deformable 3-D/3-D registration. The motion model itself is a linear direct correspondence model using the same surrogate signals as slice stacking. In X-ray fluoroscopy, only the surrogate signals need to be extracted to apply the motion model and animate the overlay in real time. For evaluation, points are manually annotated in oblique MR slices and in contrast-enhanced X-ray images. The 2-D Euclidean distance of these points is reduced from 3.85 mm to 2.75 mm in MR and from 3.0 mm to 1.8 mm in X-ray compared to the static baseline. Furthermore, the motion-compensated overlays are shown qualitatively as images and videos.

Dynamic coronary roadmapping via catheter tip tracking in X-ray fluoroscopy with deep learning based Bayesian filtering

“…For cardiac interventions including PCI, the organ motion is mainly affected by respiratory and cardiac motion. Many previous works often built a motion model parameterized by a cardiac signal derived from ECG and a respiratory signal obtained from diaphragm tracking ( [37,42,13]) or automatic PCAbased surrogate ( [15]). Some other works model only the respiratory motion in cardiac-gated images ( [35,21,30]).…”

A Tensor-Based Catheter and Wire Detection and Tracking Framework and Its Clinical Applications

“…With a tracking speed of 16 FPS, the framework can be used for real-time motion compensation, as the average maximum frame rate for modern intervention X-ray systems is 15 FPS. Using the 2D position of the proximal electrode of a CS catheter can recover up to 71% of respiratory motion, which is a similar result compared with [32]. This was compared against the static roadmap and the percentage of motion recovered is calculated as Our solution is not limited to the CS catheter and it could use any wire inserted into heart vessels or chambers as long as it remains stationary and only moves with respiratory and cardiac motions.…”

X‐ray fused with MRI guidance of pre‐selected transcatheter congenital heart disease interventions

“…Multi‐institutional studies, ideally representing all of the available vendor specific overlay software and incorporating use of pre‐acquired clinically indicated MRI scans, would be particularly helpful in capturing enough patients for the assessment of congenital interventions . Registration issues may be partially ameliorated in the future by incorporation of cardiac and respiratory motion but XFM will always be limited by the fact that the overlay is based on imaging that does not change in real‐time with the patient's condition and stage of intervention. Ultimately, if soft tissue visualization is necessary to guide interventions, rather than use a 3D image acquired before the intervention and then overlaid onto live fluoroscopy, it would be ideal to perform cases under real‐time 3D soft tissue MRI‐guidance.…”

“…Multi-institutional studies, ideally representing all of the available vendor specific overlay software and incorporating use of pre-acquired clinically indicated MRI scans, would be particularly helpful in capturing enough patients for the assessment of congenital interventions. 26 Registration issues may be partially ameliorated in the future by incorporation of cardiac and respiratory motion 21,22 but XFM will always be limited by the fact that the over-…”