MR lymphangiography using dendrimer-based contrast agents: A comparison at 1.5T and 3.0T

✍ Scribed by Yukihiro Hama; Marcelino Bernardo; Celeste A.S. Regino; Yoshinori Koyama; Martin W. Brechbiel; Murali C. Krishna; Peter L. Choyke; Hisataka Kobayashi

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 755 KB
• Volume: 57
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.21126

✦ Synopsis

Abstract

Most macromolecular contrast agents (CAs) show lower r~1~ and higher r~2~ relaxivities at 3.0T than at 1.5T. MR lymphangiography in mice using a macromolecular G6 dendrimer‐based CA was serially performed and compared at both 1.5T and 3.0T. The r~1~ and r~2~ relaxivities of the G6 CA were 25 and 78/s/mM at 1.5T and 17 and 82/s/mM at 3.0T, respectively. The lymph node (LN)‐to‐fat ratios (LN signal intensity (SI)/fat SI) of T~1~‐weighted 3D‐fast spoiled gradient‐echo (3D‐FSPGR) were 3.2 ± 0.4 (mean ± standard deviation (SD)) at 1.5T and 2.7 ± 0.3 at 3.0T (P = 0.021), and the LN‐to‐fat ratios of T~2~/T~1~‐weighted 3D‐fast imaging employing steady‐state acquisition with phase cycling (3D‐FIESTA‐C) were 1.8 ± 0.2 at 1.5T and 1.2 ± 0.4 at 3.0T (P = 0.003). Although 3D‐FSPGR successfully delineated the LNs at both 1.5T and 3.0T, 3D‐FIESTA‐C at 3.0T failed to visualize the LNs. Magn Reson Med 57:431–436, 2007. © 2007 Wiley‐Liss, Inc.