Abstract: The invention provides methods and compositions for treating a tissue disorder in a subject by parenterally administering a solution of aminolevulinic acid (ALA) or a derivative thereof that is not greater than 1.0 percent by weight into a local subcutaneous or dermal region of the subject; and administering high fluence light to said bodily area to produce a phototoxic species in said local region, thereby treating a tissue disorder in the subject.

Abstract: A method of optically detecting a tumor during surgery. The method includes imaging at least one test point defined on the tumor using a first optical imaging system to provide a first tumor image. The method further includes excising a first predetermined layer of the tumor for forming an in-vivo defect area. A predetermined contrast enhancing solution is disposed on the in-vivo defect area, which is adapted to interact with at least one cell anomaly, such as basal cell carcinoma, located on the in-vivo defect area for optically enhancing the cell anomaly. Thereafter the defect area can be optically imaged to provide a clear and bright representation of the cell anomaly to aid a surgeon while surgically removing the cell anomaly.