|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Experimental Studies |
1 From the Department of Radiology, Division of Pediatric Cardiology, University of California San Francisco, 505 Parnassus Ave, L308, San Francisco, CA 94143-0628. Received May 29, 2001; revision requested July 2; revision received September 7; accepted October 26. Address correspondence to C.B.H. (e-mail: charles.higgins@radiology.ucsf.edu).
PURPOSE: To compare the effects of various stents on magnetic resonance (MR) imaging flow volume measurements and to determine the value of a blood-pool MR imaging contrast medium in assessment of vascular stents.
MATERIALS AND METHODS: In 11 pigs, six nitinol stents (Memotherm), four platinum stents (NuMed), and one elgiloy stent (Wallstent) were placed in the main pulmonary artery under x-ray fluoroscopic guidance. MR imaging was performed 3 months after stent placement before and after injection of NC100150 contrast medium. Blood flow volumes were assessed with velocity-encoded cine MR imaging through and next to the stent. The signal-to-noise ratio and width of susceptibility artifacts of the stents also were determined. Measurements were analyzed with the paired Student t test and Bland-Altman test, where appropriate.
RESULTS: Blood flow volumes measured through the nitinol and platinum stents disclosed no significant difference between velocity-encoded cine MR imaging measurements through and next to the stent. On cine MR images, small susceptibility artifacts were observed around the nitinol and platinum stents. Signal-to-noise ratio in the stent lumen was reduced in nitinol and platinum stents when compared with that next to the stent. The elgiloy stent produced severe susceptibility artifacts, making measurement of flow volumes impossible. NC100150 injection caused no significant effect on flow volume measurements. It improved the signal-to-noise ratio of the pulmonary arterial lumen outside and, to a lesser extent, inside the stent.
CONCLUSION: Assessment of morphology and flow volumes through nitinol and platinum stents is feasible with MR imaging. Blood-pool contrast media provide persistent signal enhancement in the pulmonary artery and, to a lesser extent, in the lumina of nitinol and platinum stents.
© RSNA, 2002
Index terms: Magnetic resonance (MR), artifact, 944.93 Magnetic resonance (MR), cine studies, 944.121419 Magnetic resonance (MR), contrast media, 944.12143 Magnetic resonance (MR), vascular studies, 944.12144 Stents and prostheses, 944.1268
This article has been cited by other articles:
![]() |
T. Kuehne, M. Saeed, C. B. Higgins, K. Gleason, G. A. Krombach, O. M. Weber, A. J. Martin, D. Turner, D. Teitel, and P. Moore Endovascular Stents in Pulmonary Valve and Artery in Swine: Feasibility Study of MR Imaging-guided Deployment and Postinterventional Assessment Radiology, February 1, 2003; 226(2): 475 - 481. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOLOGY | RADIOGRAPHICS | RSNA JOURNALS ONLINE |