ANGIOGRAPHY METHOD IN ENDOSCOPIC OPTICAL COHERENCE TOMOGRAPHY Russian patent published in 2019 - IPC A61B3/00 

FIELD: medicine; measuring equipment.

SUBSTANCE: invention relates to the field of measurements for diagnostic purposes, in particular measurements for assessing the state of the cardiovascular system. Method of angiography in endoscopic optical coherence tomography involves obtaining a set of optical coherence tomography data, containing the results of multiple scans of the area of the analysed biological object, determining flow characteristics based on analysing a data set, calculating a real direction of flow based on a combination of flow characteristics, visualizing or storing the obtained results, wherein flow characteristics are determined by calculating phase difference between two or more measurements made for the same section of the analysed biological object, wherein the data set is a collection of interference signals obtained at equal time intervals at the same scanning angle and sufficient for constructing the structural images of the area of the analysed object in the endoscopic optical coherence tomography, before determining the flow characteristics, pre-processing of all interference signals of the data set by means of a threshold limitation with a predetermined threshold level of the interference signal and band-pass filtering with given lower and upper cutoff frequencies of the band-pass filter, based on the detected flow characteristics, a contrast image of blood vessels is generated based on the results of phase difference calculation, independently performing repeated determination of flow characteristics by analysing fluctuations of speckle patterns between interference signals, wherein all structural images are filtered first by convolution with a given convolutional core, and this convolution nucleus is selected so as to increase contrast of speckle structures, based on the detected flow characteristics, a contrast image of blood vessels is generated, angiogram is formed by averaging two contrast images characterizing the location of blood vessels and generated, based on the results of calculating phase difference and analysing fluctuations of speckle structures, obtained angiogram is processed by high dynamic range filter, wherein characteristics of said filter are selected so as to provide additional increase of blood vessel contrast on angiogram before its visualization or preservation.

EFFECT: using the invention enables improving quality of angiograms obtained in endoscopic OCT.

1 cl, 1 dwg