METHOD OF COLOUR DOPPLER MAPPING IN ENDOSCOPIC OPTICAL COHERENCE TOMOGRAPHY Russian patent published in 2019 - IPC A61B3/00 

FIELD: medicine.

SUBSTANCE: invention relates to measurements for diagnostic purposes, in particular measurements of blood flow characteristics in a living body. Method of colour Doppler mapping in endoscopic OCT comprises scanning an analysed object with a radiation beam, obtaining a first set of interference signals, determining the location of blood vessels, re-scanning the analysed object, obtaining a second set of interference signals, wherein the scanning region is selected based on the determined blood vessel locations, particularly the orientation of the blood vessels relative to the scanning radiation beam and the angles between the scanning beam and the blood vessels, determining blood flow based on phase shifts for a second set of interference signals, visualizing or storing information. First set and the second set of interference signals are obtained so that each of them independently contains data sufficient for constructing at least two consecutive time-dependent structural images of the endoscopic OCT. Also, signals from interference are cleaned by means of threshold limitation of interference signal level and band-pass filtering with given lower and upper cutoff frequencies of band-pass filters, and blood vessel location is determined by analysing differences in speckle structure of structural images of corresponding sets of interference signals. In determining blood flow based on phase shifts for a second set of interference signals, calculating direction of movement and velocities for each of the blood streams, resulting structural image of the analysed object is constructed by averaging structural images of the second set of interference signals, data on the location of blood vessels are averaged and taken as background for a map of locations, directions and blood flow rates, which in turn is constructed by encoding various blood flow directions with given non-repeating colours and different blood flow velocities with non-repeating shades, the resulting structural image is matched with the location map, directions and blood flow velocities with obtaining a colour Doppler cartogram, independent visualization and preservation of the resultant structural image, a map of locations, directions and blood flow rates and a colour Doppler cartogram.

EFFECT: use of the invention increases accuracy of determining rates of biological fluid flows in the analysed object.

1 cl, 1 dwg