Image-guided and -monitored renal artery stenting using only MRI.
OBJECTIVE
To demonstrate the ability of a unique interventional MR system to be used safely and effectively as the only imaging modality for all phases of MR-guided stent-supported angioplasty.


METHODS
An experimental disease model of renal stenosis was created in six pigs. An interventional MR system, which employed previously reported tools for real-time catheter tracking with automated scan-plane positioning, adaptive image parameters, and radial true-FISP imaging with steady-state precession (True-FISP) imaging coupled with a high-speed reconstruction technique, was then used to guide all phases of the intervention, including: guidewire and catheter insertion, stent deployment, and confirmation of therapeutic success. Pre- and postprocedural X-ray imaging was used as a gold standard to validate the experimental results.


RESULTS
All of the stent-supported angioplasty interventions were a technical success and were performed without complications. The average postoperative residual stenosis was 14.9%. The image guidance enabled the stents to be deployed with an accuracy of 0.98 +/- 0.69 mm. Additionally, using this interventional MRI system to guide renal artery stenting significantly reduces the procedure time, as compared to using X-ray fluoroscopy.


CONCLUSIONS
This study has clearly demonstrated the first successful treatment of renal artery stenting in an experimental animal model solely under MRI guidance and monitoring.
Department of Radiology, University Hospitals of Cleveland, Cleveland, Ohio 044106, USA.
Daniel R
DR
Elgort
Claudia M
CM
Hillenbrand
Shaoxiong
S
Zhang
Eddy Y
EY
Wong
Shervin
S
Rafie
Jonathan S
JS
Lewin
Jeffrey L
JL
Duerk
D017130:Angioplasty / Q000379:methods; D000818:Animals; D004195:Disease Models, Animal; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000009:adverse effects / Q000379:methods*; D016343:Monitoring, Intraoperative / Q000379:methods*; D012077:Renal Artery / Q000473:pathology* / Q000601:surgery*; D012078:Renal Artery Obstruction / Q000601:surgery*; D015203:Reproducibility of Results; D015607:Stents; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013552:Swine; D013997:Time Factors