Treatment systems are provided, which comprise a treatment element applying a treatment to a tissue, a stimulation element optically stimulating nerves in the tissue, a sensing unit sensing an electrical signal produced by nerves in the tissue in response to the optical stimulation, and a control unit controlling the application of the treatment according to the sensed signal. The systems and methods are used to avoid damaging nerves by sensing them during operation and immediately before local treatment application and preventing energy emission when the treatment tool is too close to specified nerves. Additional electric stimulation may be provided to enable avoidance of nerve damages on a larger scale, the treatment may be applied by a cold laser, and the control unit may control the treatment in realtime and in a closed loop and immediate prevent further treatment upon sensing optically stimulated nerves.