title: Indwelling Stent Embedded with Light-Emitting Diodes for Photodynamic Therapy of Malignant Biliary Obstruction.
abstract: OBJECTIVE
  We describe the design and preliminary characterization of a stent incorporating light-emitting diodes (LEDs) for photodynamic therapy (PDT) of malignant biliary obstruction.
  
  
  METHODS
  A prototype was constructed with red (640 nm) LEDs embedded in a 14.5 French polyurethane tube. The device was evaluated for optical power and subjected to physical and electrical tests. PDT-induced reactive oxygen species were imaged in a gel phantom.
  
  
  RESULTS
  The stent functioned at a 2.5-cm bend radius and illuminated for 6 months in saline. No stray currents were detected, and it was cool after 30 minutes of operation. Optical power of 5-15 mW is applicable to PDT. Imaging of a reactive oxygen indicator showed LED-stent activation of photosensitizer.
  
  
  CONCLUSIONS
  The results motivate biological testing and design optimization.
authors.affiliation: Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Baran
authors.affiliation: The Joint Department of Medical Imaging, University Health Network, 700 University Ave, Toronto, ON, M5G 1X6, Canada.
authors.forename: Oleg
authors.initials: O
authors.lastname: Mironov
authors.affiliation: Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA. Ashwani_Sharma@URMC.Rochester.edu.
authors.forename: Ashwani K
authors.initials: AK
authors.lastname: Sharma
authors.affiliation: Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Foster
mesh_terms: D001650:Bile Duct Neoplasms / Q000188:drug therapy*; D002779:Cholestasis / Q000188:drug therapy* / Q000628:therapy; D004867:Equipment Design; D006801:Humans; D008029:Lighting; D008953:Models, Anatomic; D055620:Optical Phenomena; D010778:Photochemotherapy / Q000295:instrumentation* / Q000379:methods; D017319:Photosensitizing Agents; D015607:Stents
chemical_list: D017319:Photosensitizing Agents
keywords: Bileduct; Biliary; Cancer; Catheter drainage; Interventional oncology