Objective:

To investigate the characteristics of low-power radiofrequency ablation in in vitro tissues.

Methods:

Thirty pieces of isolated porcine muscle tissues were divided into 10 groups (3 pieces in each group). Radiofrequency ablation was performed using high-frequency linear array ultrasound probe guided with different powers (1

2

3

4

5

6

7

8

9

10 W

respectively). The morphology and size of each ablation lesion were observed. The volume and aspect ratio of each ablation lesion were calculated.

Results:

Ellipsoid ablation lesions formed in each group except 1 W group (the tip temperature was too low to form an ablation lesion in 1 W group). The

mean volume of ablation lesion in 3 W group was the largest (1.76 cm

3

). The ablation lesion shape in 3 W group was also the closest to sphere (average aspect ratio=1.21).

Conclusion:

When the power is 3 W

the ablation lesion is the largest and is closest to sphere.