Figure 1:

Experimental implementation of the ex vivo test series.

(A) Three internally cooled bipolar radiofrequency applicators (A) were used in porcine livers (L) ex vivo.

A perfused glass tube (V) was used to simulate a natural liver vessel. The glass tube was situated in the center of the ablations, running parallel to the applicators. (B) Ablations were cut into half, orthogonally to the applicators on the height of the isolators (located at the tip of the applicator). Ablation areas were measured (dotted line). (C) An annular segmental model (Seg 1–4, …) with an adjustable segment width of “x” mm was used to compare ablations areas to an averaged mask (consisting of ablations with continuous Pringle maneuver reffered to as “ground truth”). Three areas have to be distinguished in analysis: (1) ablations are congruent (“O”); (2) an increase of ablation area compared to ground truth exists (“R”); and (3) the ablation is smaller than ground truth (cooling effects: “C”).