Related Experiment Videos
Passive tracking exploiting local signal conservation: the white marker phenomenon.
Jan-Henry Seppenwoolde1, Max A Viergever, Chris J G Bakker
1Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands. janhenry@isi.uu.nl
Magnetic Resonance in Medicine
|October 3, 2003
Summary
This study introduces "white marker tracking," a new method for passively tracking paramagnetic markers during endovascular interventions. It achieves reliable marker visualization by enhancing their positive contrast against background signals.
Area of Science:
- Medical Imaging
- Biophysics
- Interventional Radiology
Background:
- Endovascular interventions require precise tracking of medical devices and markers.
- Current tracking methods may have limitations in contrast or robustness.
- Paramagnetic markers offer potential for enhanced visualization.
Purpose of the Study:
- To present a novel passive tracking technique for paramagnetic markers.
- To exploit positive contrast for improved marker visualization during endovascular procedures.
- To demonstrate the feasibility and reliability of the proposed tracking method.
Main Methods:
- Theoretical investigation of signal dephasing and compensation by marker dipole fields.
- Experimental validation using varying marker strengths, echo-times, slice thicknesses, and gradient strengths.
- Demonstration in flow phantom and in vivo pig models.
Main Results:
- The "white marker tracking" technique relies on background signal dephasing and local gradient compensation.
- Marker appearance is predictably influenced by marker strength, echo-time, slice thickness, and gradient strength.
- Successful tracking demonstrated reliable positive contrast and significant background suppression in phantom and animal studies.
Conclusions:
- The developed white marker tracking method offers a robust and reliable approach for endovascular interventions.
- This technique enhances visualization of paramagnetic markers by achieving positive contrast and background signal suppression.
- The findings support the clinical potential of this novel passive tracking method.