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

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, to deposit doses by pencil beam scanning into a structure of interest of a patient according to a treatment plan. The method calculates the dose (rate) volume histograms for a statistically representative number N of values randomly selected within a defined confidence level in preselected tentative statistical distributions of the operating parameters and compares the obtained calculated dose (rate) volume histogram with an acceptable band of variation of a target dose (rate) volume histogram. Once a tentative statistical distribution yields N calculated dose (rate) volume histograms which all fall within the acceptable band of variation, it is set as the final statistical distribution, and the particle accelerating system can be programmed with the final statistical distribution.