TY - JOUR
T1 - Characterization of contrast enhancement in the ablation zone immediately after radiofrequency ablation of renal tumors
AU - Javadi, Sanaz
AU - Ahrar, Judy U.
AU - Ninan, Elizabeth
AU - Gupta, Sanjay
AU - Matin, Surena F.
AU - Ahrar, Kamran
PY - 2010/5
Y1 - 2010/5
N2 - PURPOSE: To characterize the degree of contrast enhancement within the ablation zone immediately after radiofrequency (RF) ablation of renal tumors. MATERIALS AND METHODS: Patients with renal tumors treated with percutaneous RF ablation at one institution between January 2004 and October 2007 were retrospectively reviewed. For each tumor, computed tomography (CT) density measurements were made at four phases (noncontrast, arterial phase, parenchymal phase, and excretory phase) in each of four CT examinations (before ablation, day 0, 1 month, and 6 months). RESULTS: A total of 36 renal tumors in 34 patients were treated with CT-guided RF ablation in 35 sessions. Before RF ablation, all tumors exhibited enhancement after intravenous administration of contrast material. The peak density was reached during the parenchymal phase, with a partial washout of contrast agent in the excretory phase. On CT images acquired immediately after RF ablation (day 0), 28 of the 36 ablated tumors (78%) exhibited clinically significant homogeneous enhancement (ie, density change >10 HU) within the ablation zone. However, contrastenhanced CT studies performed at 1 and 6 months revealed no clinically significant enhancements in any of the 36 treated tumors (mean density changes of 4 HU at 1 month and 3 HU at 6 months). CONCLUSIONS: Contrast-enhanced CT studies revealed a mild, temporary homogenous contrast enhancement of the ablation zone immediately after RF ablation of renal tumors, which should not be mistaken for a residual, unablated tumor. This enhancement in the ablation zone eventually disappears in follow-up contrast-enhanced CT studies.
AB - PURPOSE: To characterize the degree of contrast enhancement within the ablation zone immediately after radiofrequency (RF) ablation of renal tumors. MATERIALS AND METHODS: Patients with renal tumors treated with percutaneous RF ablation at one institution between January 2004 and October 2007 were retrospectively reviewed. For each tumor, computed tomography (CT) density measurements were made at four phases (noncontrast, arterial phase, parenchymal phase, and excretory phase) in each of four CT examinations (before ablation, day 0, 1 month, and 6 months). RESULTS: A total of 36 renal tumors in 34 patients were treated with CT-guided RF ablation in 35 sessions. Before RF ablation, all tumors exhibited enhancement after intravenous administration of contrast material. The peak density was reached during the parenchymal phase, with a partial washout of contrast agent in the excretory phase. On CT images acquired immediately after RF ablation (day 0), 28 of the 36 ablated tumors (78%) exhibited clinically significant homogeneous enhancement (ie, density change >10 HU) within the ablation zone. However, contrastenhanced CT studies performed at 1 and 6 months revealed no clinically significant enhancements in any of the 36 treated tumors (mean density changes of 4 HU at 1 month and 3 HU at 6 months). CONCLUSIONS: Contrast-enhanced CT studies revealed a mild, temporary homogenous contrast enhancement of the ablation zone immediately after RF ablation of renal tumors, which should not be mistaken for a residual, unablated tumor. This enhancement in the ablation zone eventually disappears in follow-up contrast-enhanced CT studies.
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U2 - 10.1016/j.jvir.2009.12.400
DO - 10.1016/j.jvir.2009.12.400
M3 - Article
C2 - 20227295
AN - SCOPUS:77956640936
SN - 1051-0443
VL - 21
SP - 690
EP - 695
JO - Journal of Vascular and Interventional Radiology
JF - Journal of Vascular and Interventional Radiology
IS - 5
ER -