Systems and methods for quality assurance of radiation therapy

A method implemented on a computing device having at least one processor and at least one storage device, comprising:

• determining a measured dose image through an electronic portal dose imaging device (EPID), the measured dose image indicating a dose distribution of radiation beams measured by the EPID, and the measured radiation beams corresponding to a planned radiation dose and a planned gantry angle;
• determining an energy fluence distribution map related to radiation beams predicted by a first portal dose prediction model, the predicted radiation beams corresponding to the planned radiation dose and the planned gantry angle;
• determining a predicted dose image based on the energy fluence distribution map and a simulated energy response curve related to the EPID, the predicted dose image indicating a dose distribution of the predicted radiation beams;
• and
• determining differences between the measured dose image and the predicted dose image by comparing the dose distributions of the measured dose image and the predicted dose image.

A non-transitory computer-readable medium, comprising at least one set of instructions, wherein when executed by at least one processor of a computer device, the at least one set of instructions directs the at least one processor to perform operations including:

• determining a measured dose image through an electronic portal dose imaging device (EPID), the measured dose image indicating a dose distribution of radiation beams measured by the EPID, and the measured radiation beams corresponding to a planned radiation dose and a planned gantry angle;
• determining an energy fluence distribution map related to radiation beams predicted by a first portal dose prediction model, the predicted radiation beams corresponding to the planned radiation dose and the planned gantry angle;
• determining a predicted dose image based on the energy fluence distribution map and a simulated energy response curve related to the EPID, the predicted dose image indicating a dose distribution of the predicted radiation beams;
• and
• determining differences between the measured dose image and the predicted dose image by comparing the dose distributions of the measured dose image and the predicted dose image.