Radiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

DOI: 10.1148/radiol.2293020368
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Meyer, J. M. A.
Right arrow Articles by Günther, R. W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Meyer, J. M. A.
Right arrow Articles by Günther, R. W.
(Radiology 2003;229:847-854.)
© RSNA, 2003

Experimental Studies

Inhibition of Neointimal Proliferation with 188Re-labeled Self-Expanding Nitinol Stent in a Sheep Model1

Julius M. A. Meyer, MD, Bernd Nowak, MD, Karl Schuermann, MD, Arno Buecker, MD, Felix Moltzahn, Arthur Kulisch, Nicole Heussen, Thomas Görgen, Udorich Büll, MD and Rolf W. Günther, MD

1 From the Departments of Diagnostic Radiology (J.M.A.M., K.S., A.B., F.M., A.K., R.W.G.), Nuclear Medicine (B.N., U.B.), Biometry (N.H.), and Textile and Macromolecular Chemistry (T.G.), University of Technology, Pauwelsstrasse 30, Aachen D-52074, Germany. Received April 6, 2002; revision requested June 17; final revision received February 25, 2003; accepted April 7. Supported by the Interdisciplinary Center for Clinical Research in Biomaterials and Tissue-Material Interaction in Implants (BMBF Project No. 01/KS 9503/9). Address correspondence to J.M.A.M.

PURPOSE: To evaluate a self-expanding rhenium 188 (188Re) radiochemically labeled radioactive stent in sheep.

MATERIALS AND METHODS: A self-expanding nitinol stent (30 mm in length, 8 mm in diameter) coated with a functionalized polymer layer was radiolabeled with 188Re. Fifty prostheses, 25 of which were radioactive (mean radioactivity, 20 MBq ± 3.8 [SD]) and 25 of which were nonradioactive, were implanted into the external iliac arteries of 25 sheep. Stent patency was assessed with angiography. Neointimal formation was assessed with intravascular ultrasonography and histologic examination 1 month (in all sheep) and 3 months (in 12 sheep) after implantation. The results were analyzed by using repeated-measures analysis of variance with two repeated factors and paired t tests for comparison at each measuring point.

RESULTS: All stents were placed successfully. Data in one animal had to be excluded from the study. After 3 months, a mean neointimal area reduction of 70 mm2 ± 55 (SD) was observed inside the radioactive stents, and a mean lumen reduction of 126 mm2 ± 39 was observed inside the nonradioactive control stents (P = .022). An edge effect was observed in the radioactive stents in that they showed an amount of neointimal formation at the edges that was similar to that seen in control stents. This neointimal formation accounted for the maximum lumen loss in the vascular segment with the stent.

CONCLUSION: As compared with a nonradioactive stent, a ß particle–emitting stent, through endovascular irradiation, significantly inhibits neointimal formation inside the stent but not at the stent edges.

© RSNA, 2003

Index terms: Animals • Arteriosclerosis, 984.721, 986.721 • Coronary vessels, stents and prostheses, 54.1269 • Dosimetry • Stents and prostheses • Stents and prostheses, radiation