Upstream direct x-ray detection

摘要

A radiation beam, for example a therapeutic radiation beam such as an IMRT or VMAT X-ray beam is monitored using a Monolithic Active Pixel Sensor (MAPS) detector. Photons of the radiation beam can interact with the MAPS detector, and the radiation beam configuration can be estimated from the determined positions of the interactions. The detector is made sufficiently thin that it interacts only very weakly with the X-ray photons. For example, less than 1 in 103 of the X-ray photons might interact with the detector. Hence, the disturbance to the X-ray beam is negligible.

主权项

1. A method of monitoring an X-ray radiation beam for treatment of a patient, the method comprising:
placing in the radiation beam a monolithic active pixel sensor (MAPS) detector between the patient and an x-ray source; exposing the MAPS detector to the radiation beam, such that photons of the radiation beam can interact with the MAPS detector wherein the MAPS detector has a thickness configured such that it interacts with a maximum of 1 in 103 photons of the X-ray beam incident on the detector; determining a position of each identified interaction; and estimating a configuration of the radiation beam delivered to the patient from the determined positions of the interactions.