Study of Saline Linked Monopolar Surface Radiofrequency (RF) Ablation of Hepatic Tumors

* To determine the depth of coagulation which is possible in human liver tissue using the saline linked RF Surface ablation with the Tissue Link floating ball.
* To determine the efficacy of the technique on surface liver tumors using saline linked RF surface ablati
* To determine a safe (non-popping upper limit) of power per area that will permit a 1 cm depth of tissue destruction without inflow occlusion an da 2 cm depth with inflow occlusion.