Systems and methods for patient monitoring for radiotherapy

A radiation therapy system comprising:

• a rotatable ring that defines a longitudinal bore with a patient area therein, wherein the rotatable ring is configured to rotate at a rate from about 60 RPM to about 200 RPM;
• a therapeutic radiation source coupled to the rotatable ring, wherein the therapeutic radiation source comprises an MV X-ray source;
• a camera located within the longitudinal bore and coupled to the rotatable ring, wherein the camera is configured to acquire camera image data of the patient area while the ring is rotating;
• and
• a controller in communication with the rotatable ring, therapeutic radiation source, and camera, wherein the controller is configured to correct motion-related imaging artifacts in the camera image data by combining image data acquired by the camera over a plurality of camera revolutions around the patient area for monitoring positional information of a patient within the patient area.

A method for monitoring positional information of a patient within a patient area within a longitudinal bore of a radiation therapy system, the method comprising:

• acquiring image data of the patient area by rotating a camera configured for a non-ionizing imaging modality around the patient area at a rate from about 60 RPM to about 200 RPM;
• correcting a motion-related imaging artifact in the acquired image data by combining image data acquired by the camera over a plurality of camera revolutions around the patient area;
• generating current patient positional information from the corrected image data;
• and
• determining changes in positional information of the patient by comparing the current patient positional information with earlier patient positional information.