COMPUTER IMPLEMENTED METHOD FOR REDUCING THE RISK OF INTERRUPTING AN IRRADIATION TREATMENT SESSION DUE TO A DEVIATION FROM A PLANNED VALUE OF AN OPERATING PARAMETER OF A PARTICLE ACCELERATING SYSTEM

The present invention concerns a computer implemented method for optimizing tolerance values of operating parameters of a particle accelerating system allowing a plurality of beamlets of particles accelerated along an irradiation axis (Z), to deposit doses by pencil beam scanning (= PBS) into a structure of interest of a patient according to a treatment plan (= TP). The method calculates the dose (rate) volume histograms (cD(R)VH) for a statistically representative number N of values randomly selected within a defined confidence level (CLj) in preselected tentative statistical distributions of the operating parameters and compares the thus obtained cD(R)VH with an acceptable band of variation (BV) of a target D(R)VH. Once a tentative statistical distribution (Tj) yields N calculated cD(R)VH which all fall within the acceptable band of variation (BV) it is set as the final statistical distribution (Tf), and the particle accelerating system can be programmed with the final statistical distribution (Tf).