Some embodiments are directed to a radiation dosage monitoring system including a model generation module configured to generate a 3D surface model of a portion of a patient undergoing radiation treatment, an image detector configured to detect Cherenkov radiation and any subsequent secondary and scattered radiation originating due to the initial Cherenkov radiation emitted from the patient, a processing module configured to determine estimations of radiation applied to the patient utilizing the images from the image detector and the 3D model, and to utilize the determined estimations of radiation applied to the patient together with data indicative of the orientation of a radiation beam inducing emission of the Cherenkov radiation at a time when the radiation beam was applied to generate a 3D internal representation of the location of the portions of a irradiated patient resulting in the emission of the Cherenkov radiation.