METHOD OF DETERMINING A POISSON COEFFICIENT FOR A WALL OF A BLOOD VESSEL BASED ON ENDOSCOPIC OPTICAL COHERENCE TOMOGRAPHY Russian patent published in 2019 - IPC A61B6/00 

FIELD: medicine; measuring equipment.

SUBSTANCE: invention relates to the field of measurements for diagnostic purposes, in particular to methods for assessing the state of the cardiovascular system by analysing the results of endoscopic OCT walls of blood vessels. Method for determining the Poisson ratio for a wall of a blood vessel based on an endoscopic OCT comprises obtaining a first structural image of the analysed biological tissue or part thereof for a time corresponding to diastole, obtaining a second structural image of the analysed biological tissue or portion thereof, for a time corresponding to systole, comparing a first structural image with a second structural image, wherein for comparison, determining pixel offset values, and for this, successively selecting control pixels on the first structural image and on the second structural image, grouping reference pixels into control pixel pairs such that each control pixel from the second structural image most likely matches a control pixel from the first structural image, wherein one control pixel can be simultaneously only in one pair of control pixels, independently determining values of pixel displacements for each pair of control pixels, wherein determined values of pixel displacements are vector, vector values of pixel displacements for each pair of control pixels are independently plotted along coordinate axes, longitudinal pixel shifts for each pair of control pixels are considered to be equal to projections of pixel displacement vectors per ordinate axis, longitudinal dimensions of the deformable region are calculated by combining longitudinal pixel displacements for all pairs of control pixels, visualization by means of a user interface. Physical value visualized by the user interface is a Poisson ratio, wherein transverse displacements of pixels for each pair of reference pixels are considered to be equal to projections of pixel displacement vectors on the abscissa, transverse dimensions of deformable area are calculated by combining transverse pixel shifts for all pairs of control pixels, value of Poisson ratio is calculated as a module from the quotient of the product of transverse displacements of pixels and longitudinal dimensions of the deformed region by product of transverse dimensions of the deformed region by longitudinal displacement of pixels.

EFFECT: use of the invention provides higher accuracy of assessing the mechanical properties of the walls of blood vessels.

1 cl, 1 dwg