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Positive visualization of MR-compatible nitinol stent using a susceptibility-based imaging technique
Caiyun Shi1, Guoxi Xie2,3, Dong Liang1
1Shenzhen Key Laboratory for MRI, Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
Quantitative Imaging in Medicine and Surgery
|April 30, 2019
Summary
A new susceptibility-based MRI method improves visualization of metallic stents and assessment of restenosis, outperforming conventional techniques like SUMO and GRASP for better clinical evaluation.
Area of Science:
- Medical Imaging
- Biomedical Engineering
- Radiology
Background:
- Metallic stents are crucial for treating arterial occlusive diseases.
- Conventional MRI faces challenges in stent visualization and restenosis assessment due to artifacts.
- Susceptibility-based MRI shows promise for visualizing metallic devices.
Purpose of the Study:
- To evaluate a susceptibility-based positive contrast MRI method for visualizing nitinol stents.
- To assess the method's efficacy in detecting stent restenosis.
- To compare its performance against established MR techniques (SUMO and GRASP).
Main Methods:
- Employed a susceptibility-based positive contrast MRI technique.
- Visualized nitinol stents and assessed for restenosis.
- Compared results with susceptibility gradient mapping (SUMO) and gradient echo acquisition for super-paramagnetic particles (GRASP).
Main Results:
- The susceptibility-based method demonstrated superior stent visualization and localization compared to SUMO and GRASP.
- Experimental results confirmed the method's feasibility in evaluating stent restenosis.
- Influence of stent orientation and spatial resolution on the method was investigated.
Conclusions:
- The susceptibility-based MRI method offers enhanced visualization and localization of metallic stents.
- This technique is capable of accurately assessing stent restenosis.
- It represents an advancement over existing MR methods for stent evaluation.
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