Value of CT Volume Imaging for Optimal Placement of Radiofrequency Ablation Probes in Liver Lesions
Section snippets
MATERIALS AND METHODS
The data of 21 patients who had hepatocellular carcinoma (n = 10), colorectal metastases (n = 9), or metastases of carcinoid tumor (n = 2) were included in this study. The mean age of all patients was 59 years (range, 46 –71 y) and there were 16 men and five women. Thirty-two hepatic lesions (mean size, 3.2 cm; range, 1.9 – 4.8 cm) were treated. Twelve patients presented with one lesion, seven patients with two lesions, and two patients with three lesions. Fourteen patients underwent one
Accuracy of Probe Placement
MPR reformations and VR reconstructions resulted in a reclassification of the needle position in 14 of 32 RF ablation procedures (44%; P = .0034). In 10 cases, probe positions considered “central” on biopsy-mode images were found to be “marginal” with MPR and VR analysis. In these cases, the probe was repositioned after initial RF ablation (Fig 2). In three procedures, probe positions considered “marginal” on biopsy-mode images were found to be “outside” with MPR and VR analysis (Fig 3). In
DISCUSSION
The success of RF ablation is in large part dependent on the correct positioning of the ablation probe (4, 5). Recognition of this relationship emphasizes the need for accurate guidance of the probe into the lesion. This study demonstrates the usefulness of collecting a limited contrast-enhanced CT spiral image data set to verify the probe position. In 13 of 32 procedures (41%), the location of the probe was downstaged based on an analysis of the spiral data set in the MPR mode, which resulted
CONCLUSION
The acquisition of a focused contrast-enhanced spiral CT data set with multiplanar reformations to verify an optimal probe location after conventional axial guidance of the probe is recommended before RF ablation of liver lesions.
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2013, Ultrasound in Medicine and BiologyCitation Excerpt :The most widely used modalities are radiofrequency ablation and microwave ablation. The success of ablative treatment is strongly dependent on complete tumor destruction, which requires both accurate placement of ablative probes in the center of lesions and a thorough understanding of the ablative range (Antoch et al. 2002; Solbiati et al. 2001). However, the local recurrence rates after treatment remain high.
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2010, Journal of Vascular and Interventional RadiologyCitation Excerpt :However, MR-guided RF ablation needs specialized MR and RF ablation equipment, has unproven clinical efficacy, and adds expense to an already costly procedure. Performing contrast-enhanced ultrasound scan or computed tomography during RF ablation provide additional modalities to immediately assess completeness of ablation and guide subsequent electrode placement (22,23), although the presence of peripheral enhancement after RF ablation may mask residual tumor and decrease its accuracy (24). The performance of a temperature-dependent technique of electrode withdrawal may represent an easier and more practical way of guiding needle placement in linear ablations.
None of the authors has identified a conflict of interest.