def get_z_origin(params, gauge_value):
        """
        Get the Z coordinate origin of the US system
        :param params: Parameters of the acquisition
        :param gauge_value: Indicator gauge value
        :return: Z coordinate
        """
        image_origin = params['start depth'] + params['axial samples']*params['axial resolution']
        z_origin = image_origin + gauge_value
        return z_origin