Region-growing algorithm
AssigneesuperDimension, Ltd.
InventorsDorian Averbuch, Yuri Kreinin
Life of this patent
Estimating the term…
Abstract
A technique for automatically generating a virtual model of a branched structure using as an input a plurality of images taken of the branched structure. The technique employs an algorithm that avoids inaccuracies associated with sub-optimal threshold settings by “patching” holes or leaks created due to the inherent inconsistencies with imaging technology. By “patching” the holes, the algorithm may continue to run using a more sensitive threshold value than was previously possible.
Claims7
A method for creating a virtual model of an anatomical structure from a three-dimensional image volume, comprising:
- providing a three-dimensional image volume created from a plurality of two-dimensional images;
- setting a threshold value, above which is indicative that an imaged voxel is not representing tissue;
- selecting a seed point voxel in said three-dimensional image volume as a starting point;
- performing a plurality of iterations, each iteration comprising:
- segmenting voxels, immediately adjacent said seed point in all desired directions, that meet or exceed said threshold value;
- determining a number of voxels segmented in this iteration;
- if said number of voxels is greater than zero, determining whether said number is large enough to indicate leakage;
- removing leaked voxels and storing them as leaked objects for post-processing
- identifying segmented voxels as seed points for next iteration if no leakage is indicated;
- detecting when said number of voxels segmented equals zero;
- performing secondary iterations on leaked objects, if any, until said number of voxels segmented equals zero, said secondary iterations comprising:
- selecting voxels in a first iteration detecting leakage for a given leaked object as seed points;
- reducing said threshold value;
- segmenting voxels, immediately adjacent said seed points in all desired directions, that meet or exceed said threshold value;
- determining a number of voxels segmented in this iteration;
- if said number of voxels is greater than zero, determining whether said number is large enough to indicate leakage;
- removing leaked voxels and storing them as leaked objects for post-processing
- identifying segmented voxels as seed points for next iteration if no leakage is indicated.
A computer readable medium storing instructions that when read by a computer perform a method for creating a virtual model of an anatomical structure from a three-dimensional image volume, comprising:
- using as a threshold, an image voxel density indicative of a fluid;
- segmenting only voxels meeting said threshold, thereby creating a virtual model of interior cavities and/or lumens of said anatomical structure, wherein the segmenting is performed as a series of iterations using a segmented voxel as a seed point and analyzing unsegmented voxels adjacent said seed point in a desired direction;
- and
- repeating said iterations using newly segmented voxels from an iteration as seed points for a next iteration until no unsegmented voxels adjacent said seed points in said desired direction remain.
Dependencies are inferred from the claim text.