Journal of the Korean Radiological Society  2006;54(6):515-523

doi:10.3348/jkrs.2006.54.6.515

Ferucarbotran-Enhanced MR Imaging of the Radiofrequency Ablation Zones in the Normal Rabbit Liver: Comparison with the Conventional MR Imaging.

Sung Hyun HONG 1 ; Seung Kwon KIM ; Seoung Wan CHAE ; Hyon Joo KWAG ; Min Hee LEE ; Young Rae LEE ; Byung Moon KIM ; Hyun Pyo HONG ; Heon HAN ; Ji Yeon LEE

Affiliations

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Keywords

Radiofrequency (RF) ablation; Liver, MR; Liver, interventional procedure; Experimental study

Country

Republic of Korea

Language

Korean

Abstract

PURPOSE: We wanted to evaluate the findings of ferucarbotran-enhanced MR imaging of the radiofrequency (RF) ablation zones in normal rabbit livers and we compared the findings with the conventional MR imaging. MATERIALS AND METHODS: RF ablation zones were created in the livers of 12 rabbits in vivo by using a 17-gauge internally cooled electrode with 1-cm active tip, and RF energy (maximum power: 30 Watt) was applied for three minutes. Three rabbits were sacrificed immediately and then at three days, two weeks and six weeks after RF ablation. Before sacrifice, the T1- and T2-weighted images (WI) and the ferucarbotran-enhanced T2*WIs were obtained and compared regarding the signal intensity of ablation zone, the laminar pattern of the signal intensity and the contrast-to-noise ratio (CNR) of the ablation zone to the liver parenchyma. RESULTS: On T1- and T2WIs, the RF ablation zones showed two to four laminar patterns of signal intensity according to the time. Meanwhile, on the ferucarbotran-enhanced T2WIs, the RF ablation zones showed high signal intensity without a laminar pattern regardless of time. The CNRs of the ablation zones to the liver parenchyma on the ferucarbotran-enhanced T2*WIs (18.2+/-5.9) were significantly higher than those of the TIWIs (1.6+/-1.5) and T2WIs (2.7+/-1.9) (p < 0.05). CONCLUSION: On the ferucarbotran-enhanced T2*WI, the RF ablation zones showed high signal intensity without a distinct laminar pattern and significantly higher lesion conspicuity than did the conventional T1- and T2WIs. Therefore, the ferucarbotran-enhanced T2*WI shows the RF ablation zone more accurately and clearly than do the conventional T1- and T2WIs.