Zusammenfassung
Ziel: Darstellung der Lymphknotenfeinstruktur inguinaler Lymphknoten (LK) mittels hochauflösender MR-Lymphographie nach interstitieller Applikation von Gadomer-17. Material und Methoden: Die hochauflösende MR-Lymphographie erfolgte nach subkutaner Injektion von 10 μmol/kg Körpergewicht Gadomer-17 in die Hinterextremitäten von zehn Hausschweinen (39 bis 46 kg) in einem 1,5-Tesla-MR-Gerät unter Verwendung einer ringförmigen Oberflächenspule. Es wurden insgesamt 20 inguinale Lymphknoten mit zwei verschiedenen hochauflösenden 3-D-Gradientenechosequenzen untersucht und zusätzlich Maximumintensitätsprojektionen nachberechnet. Die Befunde der hochauflösenden MR-Lymphogramme wurden mit den histologischen Schnitten der exzidierten Leistenlymphknoten korreliert. Ergebnisse: Die koronaren T1-gewichteten MR-Lymphogramme (TR = 20 msek, TE = 6,1 - 8,3 msek, FA = 200 ) mit einer Schichtdicke von 1 mm, einem FOV von 120 mm und einer Bildmatrix von 256 × 256 Bildpunkten, rekonstruiert auf 1024 × 1024 Bildpunkte (rekonstruierte Auflösung: 117 × 117 µm2 ) waren für die hochauflösende interstitielle MR-Lymphographie mittels Gadomer-17 zur Differenzierung von hypointensem Parenchym, hyperintensen Sinus und dilatierten Lymphgefäßen am besten geeignet. Schlussfolgerung: Die hochauflösende interstitielle MR-Lymphographie mittels Gadomer-17 erlaubt die Differenzierung verschiedener Gewebekompartimente in inguinalen LK unter Verwendung eines konventionellen 1,5-Tesla-MR-Tomographen.
Abstract
Purpose: To evaluate the microstructural anatomy of inguinal lymph nodes in pigs after interstitial MR-lymphography with the dendritic contrast agent Gadomer-17. Material and Methods: High-resolution T1-weighted MR-lymphography was performed in inguinal lymph nodes of 10 domestic pigs (39 - 46 kg) after subcutaneous injection of 10 μmol/kg body weight Gadomer-17 in the hind legs of the animals. A 1.5T MR scanner and a ring-shaped surface coil were used. Two different high-resolution gradient-echo sequences with additionally reconstructed maximum-intensity projections were evaluated in a total of 20 lymph nodes. The high-resolution MR-findings were correlated with the histologic sections of the excised inguinal lymph nodes. Results: Coronal T1-weighted 3D gradient-echo images (TR = 20 msec, TE = 6.1 - 8.3 msec, FA = 20°) with a slice thickness of 1 mm, a field-of-view of 120 mm and a matrix size of 256x256 (reconstructed to 1024x1024 voxels) yielding a reconstructed in-plane resolution of 117x117 µm2 were best suited for the high-resolution MR lymphography of inguinal lymph nodes and enabled the differentiation of the hyperintense lymph node sinuses and hypointense lymphoid parenchyma of each lymph node (100 %). Even dilated lymphatic vessels evident in the histologic specimen were best demonstrated on the MIP images. Conclusion: High-resolution interstitial MR lymphography with Gadomer-17 allows the visualization of different tissue compartments of inguinal lymph nodes. This new technique is feasible on a routine 1.5T scanner and may offer potential for the detection of micrometastases in lymph nodes of cancer patients.
Key words
Magnetic resonance (MR), contrast enhancement - lymphatic system, MR - lymphography - magnetic resonance (MR), experimental
Literatur
1
Staatz G, Nolte-Ernsting C CA, Adam G B. et al .
Interstitial T1-weighted MR-Lymphography: lipophilic, perfluorinated Gadolinium-chelates in pigs.
Radiology.
2001;
220
129-134
2
Staatz G, Nolte-Ernsting C CA. et al .
Interstitielle T1-gewichtete MR-Lymphographie mit dem neuen polymeren Kontrastmittel Gadomer-17.
Fortschr Röntgenstr.
2001;
173
1131-1136
3
Herborn C U, Vogt F M, Lauenstein T C. et al .
Assessment of normal, inflammatory, and tumor-bearing lymph nodes with contrast-enhanced interstitial magnetic resonance lymphography: preliminary results in rabbits.
J Magn Reson Imaging.
2003;
18
328-335
4
Misselwitz B, Platzek J, Weinmann H J.
Early MR lymphography with gadofluorine M in rabbits.
Radiology.
2004;
231
682-688
5
Ruehm S G, Corot C, Debatin J F.
Interstitial MR lymphography with a conventional extracellular gadolinium-based agent: assessment in rabbits.
Radiology.
2001;
218
664-669
6
Staatz G, Spuntrup E, Bucker A. et al .
Interstitielle T1-gewichtete MR-Lymphfistulographie mittels Gadomer-17 im Tierexperiment.
Fortschr Rontgenstr.
2003;
175
275-281
7
Ruehm S G, Schroeder T, Debatin J F.
Interstitial MR lymphography with gadoterate meglumine: initial experience in humans.
Radiology.
2001;
220
816-821
8
Clement O, Luciani A.
Imaging the lymphatic system: possibilities and clinical applications.
Eur Radiol.
2004;
14
1498-1507
9
Lee A S, Weissleder R, Brady T J. et al .
Lymph nodes: microstructural anatomy at MR imaging.
Radiology.
1991;
178
519-522
10
Misselwitz B, Schmitt-Willich H, Ebert W. et al .
Pharmacokinetics of Gadomer-17, a new dendritic magnetic resonance contrast agent.
Magma.
2001;
12
128-134
11
Harika L, Weissleder R, Poss K. et al .
MR lymphography with a lymphotropic T1-type MR contrast agent: Gd-DTPA-PGM.
Magn Reson Med.
1995;
33
88-92
12
Misselwitz B, Sachse A.
Interstitial MR lymphography using Gd-carrying liposomes.
Acta Radiol.
1997;
412
51-55
13
Wunderbaldinger P, Weissleder R.
Experimentelle und klinische Ansätze zur Lymphknotenbildgebung.
Radiologe.
2001;
41
121-130
14
Bellin M F, Roy C, Kinkel K. et al .
Lymph node metastases: safety and effectiveness of MR imaging with ultrasmall superparamagnetic iron oxide particles-initial clinical experience.
Radiology.
1998;
207
799-808
15
Hamm B, Taupitz M, Hussmann P. et al .
MR lymphography with iron oxide particles: dose-response studies and pulse sequence optimization in rabbits.
Am J Roentgenol.
1992;
158
183-190
16
Vassallo P, Matei C, Heston W DH. et al .
Characterization of reactive versus tumor-bearing lymph nodes with interstitial magnetic resonance lymphography in an animal model.
Invest Radiol.
1995;
30
706-711
17
Vassallo P, Matei C, Heston W DW. et al .
AMI-227-enhanced MR lymphography: usefulness for differentiating reactive from tumor-bearing lymph nodes.
Radiology.
1994;
193
501-506
18
Weissleder R, Elizondo G, Josephson L. et al .
Experimental lymph node metastases: enhanced detection with MR lymphography.
Radiology.
1989;
171
835-839
19
Weissleder R, Stark D D, Engelstad B L. et al .
Superparamagnetic iron oxide: pharmacokinetics and toxicity.
Am J Roentgenol.
1989;
152
167-173
20
Weissleder R, Elizondo G, Wittenberg J. et al .
Ultrasmall superparamagnetic iron oxide: characterization of a new class of contrast agents for MR imaging.
Radiology.
1990;
175
489-493
21
Clement O, Guimaraes R, De Kerviler E. et al .
Magnetic resonance lymphography: enhancement patterns using superparamagnetic nanoparticles.
Invest Radiol.
1994;
29
226-228
22
Guimaraes R, Clement O, Bittoun J. et al .
MR lymphography with superparamagnetic iron nanoparticles in rats: pathologic basis for contrast enhancement.
Am J Roentgenol.
1994;
162
201-207
23
Harisinghani M G, Saini S, Slater G J. et al .
MR imaging of pelvic lymph nodes in primary pelvic carcinoma with ultrasmall superparamagnetic iron oxide (combidex): preliminary observations.
J Magn Reson Imaging.
1997;
7
161-163
24
Harisinghani M G, Saini S, Weissleder R. et al .
MR lymphangiography using ultrasmall superparamagnetic iron oxide in patients with primary abdominal and pelvic malignancies: radiographic-pathologic correlation.
Am J Roentgenol.
1999;
172
1347-1351
25
Taupitz M, Wagner S, Hamm B. et al .
Interstitial MR lymphography with iron oxide particles: results in tumor-free and VX2 tumor-bearing rabbits.
Am J Roentgenol.
1993;
161
193-200
26
Taupitz M, Schmitz S, Hamm B.
Superparamagnetische Eisenoxidpartikel. Aktueller Stand und zukünftige Entwicklungen.
Fortschr Röntgenstr.
2003;
175
752-756
27
Vassallo P, Matei C, Heston W DH. et al .
Characterization of reactive versus tumor-bearing lymph nodes with interstitial magnetic resonance lymphography in an animal model.
Invest Radiol.
1995;
30
706-711
28
Anzai Y, Blackwell K E, Hirschowitz S L. et al .
Initial experience with dextran-coated superparamagnetic iron-oxide for detection of lymph node metastases in patients with head and neck cancer.
Radiology.
1994;
192
709-715
29
Mack M G, Balzer J O, Straub R. et al .
Superparamagnetic iron oxide-enhanced MR imaging of head and neck lymph nodes.
Radiology.
2002;
222
239-244
30
Nguyen B C, Stanford W, Thompson B H. et al .
Multicenter clinical trial of ultrasmall superparamagnetic iron oxide in the evaluation of mediastinal lymph nodes in patients with primary lung carcinoma.
J Magn Reson Imaging.
1999;
10
468-473
31
Taupitz M, Wallis F, Heywang-Koebrunner S H. et al .
Axillary lymph node MR imaging with Sinerem® in patients with suspected breast cancer. Proceedings of the Radiological Society of North America, Chicago.
Radiology.
1999;
213
369
32
Staatz G, Spüntrup E, Bücker A. et al .
T1-weighted MR-Lymphography after intramammary administration of Gadomer-17 in pigs.
Fortschr Röntgenstr.
2002;
174
29-32
PD Dr. Gundula Staatz
Klinik für Radiologische Diagnostik, Universitätsklinikum der RWTH Aachen
Pauwelsstraße 30
D-52074 Aachen
Phone: 02 41/8 08 85 23
Fax: 02 41/8 08 24 80
Email: staatz@rad.rwth-aachen.de