A method according to an embodiment of the invention includes inserting an endoscope at least partially into a body lumen. At least a portion of the body lumen is illuminated at a first wavelength. The portion of the body lumen is illuminated at a second wavelength different than the first wavelength. A characteristic of an area of interest when the portion of the body lumen is illuminated at the first wavelength is compared with the characteristic of the area of interest when the portion of the body lumen is illuminated at the second wavelength. A medical device or treatment parameter is selected to treat the area of interest based on the comparing. In some embodiments, the body lumen is a ureter. In such an embodiment, a composition of a kidney stone within the ureter can be identified.
