A light delivery device comprising an optical fiber having a non-feature portion and a feature portion having features that force light to couple out radially from the feature portion and provide a desired radial light output pattern. A method of photodisinfection of a cavity comprising of providing this device, apply a photosensitizing composition to treatment site within the cavity, and inserting at least a portion of the device into the cavity and applying light delivered by the device from a light source to the treatment site within the cavity at a wavelength absorbed by the photosensitizing composition so as to inhibit or eliminate microbes located at the treatment site. The present invention also includes a method of making the device and a treatment kit containing the device and a container containing a photosensitizing composition.
