Patent ID: 8848995

Claim:
A method of classification of portions of images of a set of images acquired by means of a system of computerized axial tomography, said portion of images corresponding to faecal residues e of a colorectal region, each image comprising a plurality of voxels ( 2 ) each having a predetermined intensity value related to the attenuation presented by the corresponding sample of the sampled volume, said image showing: at least one portion of colon ( 6 a , 6 b , 6 c , 6 d ) comprising: at least one area of tagged material ( 10 ) comprising at least one area of faecal residue ( 10 a ) corresponding to tagged faecal residues present in the colon and at least one area of tissue affected by tagging ( 10 b ) corresponding to tissues of the colon located in contact with the faecal residues; at least one area of air ( 8 ) corresponding to the air contained in the colon comprising an the area of pure air ( 8 a ) not influenced by the faecal residues; the method comprising the operations of: identifying ( 100 ), using a computer, on the basis of a predetermined criterion of identification based on the intensity values, first connected regions comprising connected voxels ( 2 ) having an intensity value exceeding a threshold; identifying, using a computer, within the said first connected regions, a plurality of connected regions of tagged material comprising voxels ( 2 ) representing the area of tagged material ( 10 ); classifying ( 104 ), using a computer, each voxel ( 2 ) of the said plurality of connected regions of tagged material on the basis of a trained classifier specific for each of said plurality of connected regions of tagged material, said trained classifier being obtained, for each connected region, by: identifying a plurality of variables which characterize the tagged material ( 10 ); associating each voxel ( 2 ) with a vector containing the values of said plurality of variables; selecting a classifier and training said classifier by providing to said classifier the values of variables of all the voxels ( 2 ) belonging to said connected region of tagged material thus obtaining a specific trained classifier; and inputting the vectors into said specific trained classifier which identify voxels ( 2 ) corresponding to said area of faecal residue ( 10 a ) and voxels ( 2 ) corresponding to said area of tissue affected by tagging ( 10 b ).