A system (101) for treatment of an epithelial tissue layer (3) is provided. The system comprises a reservoir (107), for containing an amount of a flowable medium, arranged to enable the medium, when contained in the reservoir, to be in contact with a surface (5) of the epithelial tissue layer, a light source (109) for generating a laser beam (11) during at least a predetermined pulse time, and an optical system for focusing the laser beam into a focal spot (15), and for positioning the focal spot in a target position. The target position of the focal spot is within the reservoir and within the medium, when contained in the reservoir, and the dimension of the focal spot and the power of the generated laser beam are such that, in the focal spot, the laser beam has a power density, which is above the characteristic threshold value for the medium, above which, for the predetermined pulse time, a laser induced optical breakdown event occurs in the medium. A method for treatment of an epithelial tissue layer is also provided.
