title: Performance of a contact textile-based light diffuser for photodynamic therapy.
abstract: BACKGROUND
  Medical textiles offer a unique contact opportunity that could provide value-added comfort, reliability, and safety for light or laser-based applications. We investigated a luminous textile diffuser for use in photodynamic therapy.
  
  
  METHODS
  Textile diffusers are produced by an embroidery process. Plastic optical fibers are bent and sewn into textile to release light by macrobending. A reflective backing is incorporated to improve surface homogeneity, intensity, and safety. Clonogenic assay (MCF-7 cells) and trypan blue exclusion (NuTu19 cells) tests were performed in vitro using 0.1μg/ml m-THPC with three textile diffusers and a standard front lens diffuser. Heating effects were studied in solution and on human skin. PDT application in vivo was performed with the textile diffuser on equine sarcoids (three animals, 50mW/cm(2), 10-20J) and eight research animals. Lastly, computer simulations were performed to see how the textile diffuser might work on a curved object.
  
  
  RESULTS
  At low fluency rate, there is a trend for the textile diffuser to have lower survival rates than the front lens diffuser for both cell lines. The textile diffuser was observed to retain more heat over a long period (>1min). All animals tolerated the treatments well and showed similar initial reactions. The simulations showed a likely focusing effect in a curved geometry.
  
  
  CONCLUSIONS
  The initial feasibility and application using a textile-based optical diffuser has been demonstrated. Possibilities that provide additional practical advantages of the textile diffuser are discussed.
authors.affiliation: Research Division of Gynecology, Department of OB/GYN, University Hospital, Zürich CH-8091, Switzerland.
authors.forename: Tania
authors.initials: T
authors.lastname: Khan
authors.affiliation: Research Division of Gynecology, Department of OB/GYN, University Hospital, Zürich CH-8091, Switzerland; Institute for Biomedical Engineering, ETH Zürich CH-8092, Switzerland.
authors.forename: Merthan
authors.initials: M
authors.lastname: Unternährer
authors.affiliation: Research Division of Gynecology, Department of OB/GYN, University Hospital, Zürich CH-8091, Switzerland; Section of Diagnostic Imaging and Radiation Oncology, VETSUISSE faculty, University of Zürich, Zürich CH-8057, Switzerland.
authors.forename: Julia
authors.initials: J
authors.lastname: Buchholz
authors.affiliation: Section of Diagnostic Imaging and Radiation Oncology, VETSUISSE faculty, University of Zürich, Zürich CH-8057, Switzerland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kaser-Hotz
authors.affiliation: Empa - Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Protection and Physiology, St. Gallen CH-9014, Switzerland.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Selm
authors.affiliation: Empa - Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Protection and Physiology, St. Gallen CH-9014, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Rothmaier
authors.affiliation: Research Division of Gynecology, Department of OB/GYN, University Hospital, Zürich CH-8091, Switzerland.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Walt