Electro-surgical needle apparatus
First Claim
1. Surgical apparatus for treating tumours in internal organs or bones of a human patient, the apparatus comprising a penetrative needle assembly for penetrating into an internal organ or bone of the human patient and ablating tumour tissue therein, said penetrative needle assembly comprising at least one cathode in an ablation zone of the needle assembly for hydrating, by electro-endosmosis, target tumour tissue in the ablation zone, an AC source coupled to the penetrative needle assembly for supplying ablating power of at least 5 W thereto, a DC source for biasing said cathode to a negative potential to induce said electro-endosmosis, wherein said AC source and said DC source are provided with switching means for inducing said electro-endosmosis prior to or simultaneously with ablating said tumour tissue in the ablation zone.
2 Assignments
0 Petitions
Accused Products
Abstract
A needle assembly (N) for RF ablation of target tissue in e.g. the liver (L) of a patient comprises a radial array of electrodes (1) in the form of loops which can be expanded by feeding the proximal ends of the Y electrodes along the bore of the needle assembly. An RF power supply (2) is connection between the array of electrodes and a skin pad (P) in contact with the skin (S) of a patient and, in accordance with the invention, is biased by a DC power supply 4 which generates electro-osmotic and/or electrolytic effects in the target tissue. In particular, chloride ions are discharged to generate chlorine which has a potent cytocidal effect and water can be attracted to the array of electrodes by electro-osmosis, thereby alleviating the problems of low electrical and thermal conductivity encountered with conventional apparatus.
60 Citations
29 Claims
- 1. Surgical apparatus for treating tumours in internal organs or bones of a human patient, the apparatus comprising a penetrative needle assembly for penetrating into an internal organ or bone of the human patient and ablating tumour tissue therein, said penetrative needle assembly comprising at least one cathode in an ablation zone of the needle assembly for hydrating, by electro-endosmosis, target tumour tissue in the ablation zone, an AC source coupled to the penetrative needle assembly for supplying ablating power of at least 5 W thereto, a DC source for biasing said cathode to a negative potential to induce said electro-endosmosis, wherein said AC source and said DC source are provided with switching means for inducing said electro-endosmosis prior to or simultaneously with ablating said tumour tissue in the ablation zone.
Specification