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.
Elgort
Daniel R
DR
Department of Radiology, University Hospitals of Cleveland, Cleveland, Ohio 044106, USA.
Hillenbrand
Claudia M
CM
Zhang
Shaoxiong
S
Wong
Eddy Y
EY
Rafie
Shervin
S
Lewin
Jonathan S
JS
Duerk
Jeffrey L
JL
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