Discrimination of Benign and Malignant Lymph Nodes at 7.0T Compared to 1.5T Magnetic Resonance Imaging Using Ultrasmall Particles of Iron Oxide: A Feasibility Preclinical Study

作者：Kinner Sonja^*; Maderwald Stefan; Albert Juliane; Parohl Nina; Corot Claire; Robert Philippe; Baba Hideo A; Barkhausen Joerg

来源：Academic Radiology, 2013, 20(12): 1604-1609.

DOI：10.1016/j.acra.2013.09.004

• Magnetic resonance imaging
• lymphography
• contrast agents
• ultrasmall particles of iron oxide (USPIO)
• 7T MRI

Rationale and Objectives: To investigate the feasibility and performance of 71 magnetic resonance imaging compared to 1.51 imaging to discriminate benign (normal and inflammatory changed) from tumor-bearing lymph nodes in rabbits using ultrasmall particles of iron oxide (USPIO)-based contrast agents. %26lt;br%26gt;Materials and Methods: Six New Zealand White rabbits were inoculated with either complete Freund%26apos;s adjuvant cell suspension (n = 3) to induce reactively enlarged lymph nodes or with VX2 tumor cells to produce metastatic lymph nodes (n = 3). Image acquisition was performed before and 24 hours after bolus injection of an USPIO contrast agent at 1.5T and afterward at 71 using T1-weighted and T2*-weighted sequences. Sensitivities, specificities, and negative and positive predictive values for the detection of lymph node metastases were calculated for both field strengths with histopathology serving as reference standard. Sizes of lymph nodes with no, inflammatory, and malignant changes were compared using a Mann-Whitney U-test. %26lt;br%26gt;Results: All 24 lymph nodes were detected at 1.51 as well as at 71. At 1.51, sensitivity amounted to 0.67, while specificity reached a value of 1. At the higher field strength (71), imaging was able to reach sensitivity and specificity values of 1. No statistical differences were detected concerning lymph node sizes. %26lt;br%26gt;Conclusions: Magnetic resonance lymphography with USPIO contrast agents allows for differentiation of normal and reactively enlarged lymph nodes compared to metastatic nodes. First experiments at 71 show promising results compared to 1.5T, which have to be evaluated in further trials.

• 出版日期2013-12