A system for delivering light to a curved surface of a tissue of a subject. The system includes a light source； an optical coupler coupled to the light source； and a flexible waveguide coupled to the optical coupler. The waveguide has a first end and a second end with an elongated flat portion therebetween. Light from the light source is emitted substantially uniformly from along the elongated flat portion of the flexible waveguide, thereby delivering light substantially uniformly along the curved surface of the tissue.
