Flexible device for topical application of PDT

#1. Field of the Invention

#The invention concerns electromagnetic delivery systems for use of photodynamic therapy in topical applications.

#2. Information Disclosure Statement

#FIG. 1A—Schematic Diagram of a preferred embodiment of the present invention

#FIG. 1B—3-Dimensional picture of two variations of a preferred embodiment

#FIG. 1C—3-Dimensional picture of a preferred embodiment as applied to a surface

#A device for the application of therapeutic radiation is disclosed that both increases the safety of a radiation procedure for the patient and practitioner, and also reduces the need for inconvenient and potentially bulky safety equipment. The treatment device is especially well suited for photodynamic therapy, but may be utilized in any treatment incorporating electromagnetic radiation.

#The device comprises two main parts: an optical waveguide and a conformable light conducting material for contact with the treatment site. The waveguide may be any light conducting device such as an optical fiber. In a preferred embodiment, a rectangular waveguide is utilized to produce a uniform beam over a treatment area. The conducting material has the additional feature of being transmissive to a predetermined treatment radiation wavelength for the surface area which is in contact with the treatment surface, while being non-transmissive for that area not in contact with the treatment surface. In this way, treatment radiation is permitted to travel from a radiation source and directly to the treatment site, but any treatment radiation that is directed away from the treatment site will be absorbed or reflected back within the conducting material.

#In a preferred embodiment, the reflective area of the conducting material is in the form of a reflective coating on the portion of the outer surface that does not come into contact with the treatment area. In a preferred embodiment, this coating is a metallic foil. The reflectivity of the coating has the additional benefit of increasing the efficiency of the treatment by reflecting misdirected radiation back onto the treatment site. Variable coatings may be used for different purposes. In one embodiment, the foil is reflective for all radiation. In another embodiment, the foil is reflective only for the treatment radiation, allowing the user to visualize the treatment site during irradiation. In yet another embodiment, the coating is reflective for a preselected range of wavelengths that may be considered harmful.