ИСТИНА

In clinical practice, and especially in stereotactic radiotherapy planning, the significance of diffusion-weighted imaging (DWI) is growing. This makes the existence of software capable of quickly processing and reliably visualizing diffusion data, as well as equipped with tools for their analysis in terms of different tasks. We are developing the «MRDiffusionImaging» software on C++. The subject part has been moved to separate class libraries and can be used on various platforms. The «MRDiffusionImaging» software is equipped with a unique set of tools for working with diffusion images. An algorithm for "masking" diffusion MRI series based on T2-weighted images was developed to exclude tissues that are not related to the area of interest from the analysis. A tool for calculating the coefficient of average diffusion and fractional anisotropy (FA) has been created, on the basis of which it is possible to build quantitative maps for solving various clinical tasks. Clustering and segmenting images functionality based on the k-means method has been created to individualize the clinical target volume and further assessment of response to the treatment. White matter tractography was realized using two algorithms: deterministic (fiber assignment by continuous tracking) and global approach provided by Hough transform. The second algorithms tests candidate curves in the voxel, assigning to each one a score computed from the diffusion data, and then select the curves with the highest scores as the potential anatomical connections. The limitations of the algorithm of fiber assignment by continuous tracking include the following: 1) overestimation of the FA threshold leads to the difficulty of visualizing tracts in the area of cerebral edema and subcortical regions of the brain; 2) a decrease of the step size leads to a decrease in the number of tracts; 3) lack of information about the error in the fiber tracking procedure; 4) the impossibility of resolving crossing and “kissing” tracts. The «MRDiffusionImaging» will improve the efficiency and accuracy of diagnostics and stereotactic radiotherapy of intracranial pathology. As part of further work, it is planned to improve the developed tools using advanced methods, test the tools on a group of patients with glioblastomas and functional pathologies, and develop a draft methodology for using diffusion in practical radiation therapy for consideration and adoption in professional the radiotherapy community.