Method of online authentication of accelerator out-beam accuracy in radiation therapy

Abstract

The invention provides a method of online authentication of accelerator out-beam accuracy in radiation therapy. The method utilizes an X-ray source and a two-dimensional flat-panel detector which rotate around a patient to measure two-dimensional transmission dose distribution in real time after a beam transmits through a target section of the patient, calculates the position sequence of each sub-ranges multi-leaf collimator blade of the beam according to the two-dimensional transmission dose distribution, and combines with each sub-ranges monitor unit (Monitor Units, for short Mu) to reconstruct a beam intensity graph, carries out comparison and evaluation on the reconstruction beam intensity graph and a treatment planning system output intensity graph, and verifies the accuracy of the accelerator out-beam intensity. The method overcomes the defect that the prior art cannot online authenticate the accelerator out-beam accuracy in real time when the patient is treated actually, and the method is not restricted by a radiation therapy machine and the multi-leaf collimator type and has the general applicability.

Description

technical field [0001] The invention relates to the technical field of on-line verification of radiotherapy instruments, in particular to a method for on-line verification of the beam output accuracy of an accelerator in radiotherapy. Background technique [0002] Accurate radiotherapy technology has developed from the original three-dimensional conformal radiotherapy (CRT) to the current rotary intensity-modulated radiotherapy (VMAT). The radiotherapy plan is becoming more and more complex, and the requirements for the output accuracy of medical accelerators are also getting higher and higher. During radiation therapy, the drift of the output dose of the medical accelerator and the inaccurate positioning of the multi-leaf collimator (MLC) may cause insufficient dose in the target area of ​​​​tumor patients or overdose in crisis organs, seriously affecting the cure rate of tumors, which makes the dose verification in radiotherapy become more and more important. [0003] The...

AI Technical Summary

Problems solved by technology

[0006] In view of the shortcomings of traditional verification methods, the existing radiation therapy technology can only perform dose verification through simple phantoms before radiotherapy, and cannot verify the accuracy of the beam output of the accelerator online when treating patients, and the traditional dose verification method is time-consuming and laborious. Insufficient, the present invention provides a method for online verification of the beam output accuracy of the accelerator in radiotherapy. With the help of a two-dimensional flat panel detector and a fast data processing platform that can rotate synchronously with the radiation source, the position of the leaf sequence of the multi-leaf grating is detected in real time, combined with The beam intensity reconstructed by sub-field Mu is compared and evaluated with the output beam intensity of the treatment planning system, and the accuracy of the beam output of the accelerator is verified in an online manner

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