Premium
Positive contrast MR‐lymphography using inversion recovery with ON‐resonant water suppression (IRON)
Author(s) -
Korosoglou Grigorios,
Tang Lijun,
Kedziorek Dorota,
Cosby Kenyatta,
Gilson Wesley D.,
Vonken EvertJan,
Schär Michael,
Sosnovik David,
Kraitchman Dara L.,
Weiss Robert G.,
Weissleder Ralf,
Stuber Matthias
Publication year - 2008
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.21337
Subject(s) - lymph , nuclear medicine , ferumoxytol , magnetic resonance imaging , paraaortic lymph nodes , medicine , nuclear magnetic resonance , materials science , radiology , pathology , cancer , physics , metastasis
Purpose To investigate the utility of inversion recovery with ON‐resonant water suppression (IRON) to create positive signal in normal lymph nodes after injection of superparamagnetic nanoparticles. Materials and Methods Experiments were conducted on six rabbits, which received a single bolus injection of 80 μmol Fe/kg monocrystalline iron oxide nanoparticle (MION‐47). Magnetic resonance imaging (MRI) was performed at baseline, 1 day, and 3 days after MION‐47 injection using conventional T 1 ‐ and T 2 *‐weighted sequences and IRON. Contrast‐to‐noise ratios (CNR) were measured in blood and in paraaortic lymph nodes. Results On T 2 *‐weighted images, as expected, signal attenuation was observed in areas of paraaortic lymph nodes after MION‐47 injection. However, using IRON the paraaortic lymph nodes exhibited very high contrast enhancement, which remained 3 days after injection. CNR with IRON was 2.2 ± 0.8 at baseline, increased markedly 1 day after injection (23.5 ± 5.4, P < 0.01 vs. baseline), and remained high after 3 days (21.8 ± 5.7, * P < 0.01 vs. baseline). CNR was also high in blood 1 day after injection (42.7 ± 7.2 vs. 1.8 ± 0.7 at baseline, P < 0.01) but approached baseline after 3 days (1.9 ± 1.4, P = NS vs. baseline). Conclusion IRON in conjunction with superparamagnetic nanoparticles can be used to perform ‘positive contrast’ MR‐lymphography, particularly 3 days after injection of the contrast agent, when signal is no longer visible within blood vessels. The proposed method may have potential as an adjunct for nodal staging in cancer screening. J. Magn. Reson. Imaging 2008;27:1175–1180. © 2008 Wiley‐Liss, Inc.