title: A radiofrequency electrode catheter-guide wire system for arterial occlusion.
abstract: OBJECTIVE
  To describe the design of a radiofrequency (RF) electrode catheter/guide wire system to allow endovascular coagulation of vessels.
  
  
  METHODS
  A circuit was created by modifying an ordinary microcatheter. An electrically conductive ring was placed at a microcatheter tip, and an extension lead at the hub site. They were each connected to an inherent coil mesh. The rings (ie, cathodes) were 1, 3, 5, 10, and 20 mm in length. In egg white, a coagulation study was performed by changing the length of the guide wire (ie, anode; 1, 3, 5, 10, 20, and 40 mm) in each cathode at 20 W. The coagulation time and site were analyzed. In rabbits, the renal artery was ablated with the use of a 20-mm cathode and 10-mm anode.
  
  
  RESULTS
  In the egg white study, the coagulation time was proportionally increased and was dependent on the lengths of the cathode and anode (P < .05). Coagula developed at the anode to the 3-mm protrusion for the 1-mm cathode, to the 5-mm protrusion for the 3-mm cathode, to the 5-mm protrusion for the 5-mm cathode, to the 10-mm protrusion for the 10-mm cathode, and to the 20-mm protrusion for the 20-mm cathode. In rabbits, the renal artery was successfully occluded. Pathologic examination showed occlusion of the renal artery with organization, and the presence of a necrotic arterial wall with fibrosis, inflammation, and intact internal elastic lamina.
  
  
  CONCLUSIONS
  The RF electrode catheter/guide wire system successfully coagulated egg white and occluded the rabbit renal artery.
authors.affiliation: Department of Radiology, Chung-Ang University Hospital, 224-1 Heukseokdong, Dongjak-gu, Seoul 156-755, Korea. kwakbk@cau.ac.kr
authors.forename: Byung Kook
authors.initials: BK
authors.lastname: Kwak
authors.forename: Woong Jae
authors.initials: WJ
authors.lastname: Lee
authors.forename: Sungjoon
authors.initials: S
authors.lastname: Lim
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Shim
authors.forename: Gil Soo
authors.initials: GS
authors.lastname: Kim
authors.forename: Dong Un
authors.initials: DU
authors.lastname: Kim
mesh_terms: D000818:Animals; D017115:Catheter Ablation / Q000295:instrumentation*; D057785:Catheters; D004527:Egg Proteins / Q000737:chemistry; D004566:Electrodes; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D004867:Equipment Design; D008297:Male; D008422:Materials Testing; D008904:Miniaturization; D023421:Models, Animal; D011489:Protein Denaturation; D011817:Rabbits; D012077:Renal Artery / Q000473:pathology / Q000601:surgery*
chemical_list: D004527:Egg Proteins