Abstract: A method and system are presented for use in determining one or more parameters of a subject. A region of interest of the subject is irradiated with acoustic tagging radiation, which comprises at least one acoustic tagging beam. At least a portion of the region of interest is irradiated with at least one electromagnetic beam of a predetermined frequency range. Electromagnetic radiation response of the at least portion of the region of interest is detected and measured data indicative thereof is generated. The detected response comprises electromagnetic radiation tagged by the acoustic radiation. This enables processing of the measured data indicative of the detected electromagnetic radiation response to determine at least one parameter of the subject in a region corresponding to the locations in the medium at which the electromagnetic radiation has been tagged by the acoustic radiation, and outputting data indicative of the at least one determined parameter.