title: Percutaneous intraductal radiofrequency ablation for clearance of occluded metal stent in malignant biliary obstruction: feasibility and early results.
abstract: OBJECTIVE
  The major complication occurring with biliary stents is stent occlusion, frequently seen because of tumour in-growth, epithelial hyperplasia, and sludge deposits, resulting in recurrent jaundice and cholangitis. We report a prospective study with the results of first in man percutaneous intraductal radiofrequency (RF) ablation to clear the blocked metal stents in patients with malignant biliary obstruction using a novel bipolar RF catheter.
  
  
  METHODS
  Nine patients with malignant biliary obstruction and blocked metal stents were included. These patients underwent intraductal biliary RF ablation through the blocked metal stent following external biliary decompression with an internal-external biliary drainage.
  
  
  RESULTS
  All nine patients had their stent patency restored successfully without the use of secondary stents. Following this intervention, there was no 30-day mortality, haemorrhage, bile duct perforation, bile leak, or pancreatitis. Of the nine patients, six are alive and three patients are dead with a median follow-up of 122 (range 50-488) days and a median stent patency of 102.5 (range 50-321) days. Six patients had their stent patent at the time of last follow-up or death. Three patients with stent blockage at 321, 290, and 65 days postprocedure underwent percutaneous transhepatic drain insertion and repeat ablation.
  
  
  CONCLUSIONS
  In this selective group of patients, it appears that this new approach is safe and feasible. Efficacy remains to be proven in future, randomized, prospective studies.
authors.affiliation: HPB Unit, Department of Surgery, Hammersmith Hospital, Imperial College, London, W12 0NN, UK, madhava.pai@imperial.ac.uk.
authors.forename: Madhava
authors.initials: M
authors.lastname: Pai
authors.forename: Vlastimil
authors.initials: V
authors.lastname: Valek
authors.forename: Andrasina
authors.initials: A
authors.lastname: Tomas
authors.forename: Attila
authors.initials: A
authors.lastname: Doros
authors.forename: Pietro
authors.initials: P
authors.lastname: Quaretti
authors.forename: Rita
authors.initials: R
authors.lastname: Golfieri
authors.forename: Cristina
authors.initials: C
authors.lastname: Mosconi
authors.forename: Nagy
authors.initials: N
authors.lastname: Habib
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D001653:Bile Ducts, Intrahepatic; D017115:Catheter Ablation / Q000379:methods*; D002758:Cholangiography; D002779:Cholestasis / Q000000981:diagnostic imaging / Q000601:surgery*; D003251:Constriction, Pathologic; D019299:Decompression, Surgical; D004322:Drainage; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000601:surgery*; D011846:Radio Waves; D015607:Stents / Q000009:adverse effects*; D016896:Treatment Outcome