Systems and methods for lesion assessment

Ablation visualization and monitoring systems and methods are provided. In some embodiments, such methods comprise applying ablation energy to a tissue to form a lesion in the tissue, illuminating the tissue with a light to excite NADH in the tissue, wherein the tissue is illuminated in a radial direction, an axial direction, or both, monitoring a level of NADH fluorescence in the illuminated tissue to determine when the level of NADH fluorescence decreases from a base level in the beginning of the ablating to a predetermined lower level, and stopping ablation of the tissue when the level of NADH fluorescence reaches the predetermined lower level.