received by the International Bureau on 09 July 2014 (09.07.14)

1.- Computer implemented method for identifying channels in a 3D data volume, said channels being passage-like structures of a 3D object within said 3D data volume, which comprises:

a) obtaining a 3D data volume of the object containing, directly or on a sub- volume isolated therefrom, at least two different data sub-volumes identified based on physical parameter values representative of physical properties of said object, and termed as: zone S and zone BZ; and

b) generating zone S and zone BZ patches from, respectively, said at least two sub-volumes;

wherein the method is characterised in that it further comprises:

c) automatically identifying possible channels, in said zone BZ patches, by means of automatically obtaining candidate channels regions, as follows:

c.1 ) dilating at least the perimeters of the zone S patches;

c.2) considering as candidate channel points (CCP) the perimeter points that intersect the perimeter of adjacent zone S patches, and/or the perimeter points that intersect with the same perimeter of the same zone S patch, before reaching a maximum dilation and lie within a zone BZ patch, and

c.3) determining that adjacent candidate channel points (CCP) form a candidate channel region (CCR).

2 - The computer implemented method of claim 1 , comprising performing said channels identification using a layered approach, as follows:

- performing said patches generation of step b) by means of:

b.1) defining a series of layers representing sections of at least part of the 3D volume or of said sub-volume isolated therefrom, said layers being polygonal meshes; and

b.2) generating patches regarding zone S and zone BZ, from the intersection of the at least two sub-volumes with the layers, defined at b.1), interpolated therein; and

- performing said automatic identification of step c) bi-dimensionally on at least one of the defined layers, where the dilation of said sub-step c.1) is performed regarding the zone S patches included in said at least one of the defined layers, and said sub-step c.2) comprises considering as candidate channel points (CCP) the perimeter points that intersect the perimeter of adjacent zone S patches,

3.- The computer implemented method of claim 2, wherein: - said at least two different sub-volumes are at least three sub-volumes identified, based on voxel intensity values and/or colour values, as: zone H, zone S and zone BZ;

- said step b) comprises generating zone H, zone S and zone BZ patches from, respectively, said at least three sub-volumes; and

- said sub-step b.2) comprises generating patches regarding zone H, zone S and zone BZ, from the intersection of the at least three sub-volumes with the layers, defined at b.1), interpolated therein.

4. - The computer implemented method of claim 1 or 2, wherein said physical parameter is associated to at least one of absorption or reflection of light, magnetic or electromagnetic radiation, temperature, electricity, signal intensity, signal phase, time, frequency and colour, or a combination thereof.

5. - The computer implemented method of claim 1 , wherein:

at step a):

- said obtaining of said 3D volume comprises obtaining an Electro Anatomical Mapping, EAM, 3D volume from memory means; and

- said zone S and zone BZ sub-volumes are identified based on values of an electrical parameter and/or of a parameter associated thereto;

the method comprising:

- performing said patches generation of step b) by means of:

b.1) retrieving at least one EAM 3D polygonal mesh from said EAM 3D volume or said sub-volume isolated therefrom; and

b.2) generating patches regarding zone S and zone BZ on respective zones of said at least one EAM 3D polygonal mesh coincident with or constituted by the at least two identified sub-volumes;

- and performing said automatic identification of step c) bi-dimensionally on said at least one EAM 3D polygonal mesh, where the dilation of said sub-step c.1 ) is performed regarding the zone S patches included in said at least one EAM 3D polygonal mesh, and said sub-step c.2) comprises considering as candidate channel points (CCP) the perimeter points that intersect the perimeter of adjacent well-defined zone (S) patches.

6. - The method of claim 5, wherein said at least one EAM 3D polygonal mesh is said EAM 3D volume or said sub-volume isolated therefrom, and said zone S and zone BZ patches are constituted by the at least two identified sub-volumes.

7. - The computer implemented method of claim 5 or 6, wherein:

- said at least two different sub-volumes are at least three sub-volumes identified as: zone H, zone S and zone BZ; - said step b) comprises generating zone H, zone S and zone BZ patches from, respectively, said at least three sub-volumes; and

- said sub-step b.2) comprises generating patches regarding zone H, zone S and zone BZ on respective zones of said at least one EAM 3D polygonal mesh coincident with or constituted by the at least three identified sub-volumes.

8.- The method of claim 2, 3, 5, 6 or 7, wherein said step c) comprises automatically obtaining candidate channel regions bi-dimensionally on at least two of the defined layers or on at least two EAM 3D polygonal meshes, by means of said steps c.1) to c.3).

9.- The method of claim 2, 3, 5, 6, 7 or 8, wherein said dilation of step c.1) is performed radially and uniformly.

10. - The method of claim 3 or 7, further comprising a step d) for identifying the possible channels by means of automatically obtaining candidate channel regions three- dimensionally across at least two layers of said layers defined at b.1) or across at least two EAM 3D polygonal meshes retrieved at b.1), for finding channels running through different layers or different EAM 3D polygonal meshes.

11. - The method of claim 10, comprising performing said step d) as follows:

d.1) for each zone BZ patch in a layer or EAM 3D polygonal mesh whose perimeter is completely surrounded by a zone S patch, a representative number of points of the zone BZ patch are classified as candidate channel points (CCP);

d.2) for each zone BZ patch containing candidate channel points (CCP), these are projected towards at least two other of said layers or EAM 3D polygonal meshes to check for intersections, and when they fall on a zone H patch or when they fall on a zone BZ patch which perimeter is at least in part in contact with a zone H patch they are classified as candidate exit points (CEP); and

d.3) candidate channel regions (CCR) are defined as those regarding a path running across layers or EAM 3D polygonal meshes through links connecting two groups of candidate exit points (CEP), and containing one or more candidate channel points (CCP).

12.- The method of claim 11 , wherein said step d.2) further comprises for those candidate channel points (CCP) of a zone BZ patch which as a result of said projections fall on a zone BZ patch, of the layer or EAM 3D polygonal mesh on which they are projected, whose perimeter is completely surrounded by a zone S patch, classifying a representative number of points of said latter zone BZ patch as candidate channel points (CCP), and classifying both groups of candidate channel points (CCP) as linked.

13.- The method of claim 11 or 12, comprising performing said projections of step d.2) towards a plurality of said layers or EAM 3D polygonal meshes, in a number bigger than two, until said two groups of candidate exit points (CEP) are found, at step d.3), on two respective layers or EAM 3D polygonal meshes.

14.- The method of claim 11 , 12 or 13, comprising using graphs and search algorithms to verify the existence of said links between each pair of groups of candidate exit points (CEP), one per layer or EAM 3D polygonal mesh.

15. - The method of any of claims 11 to 14, comprising performing a merging of the results of said steps c.3) and d.3) and an automatic filtering of the candidate channel regions (CCR) according to predetermined requirements.

16. - The method of claim 1 , wherein said patches are volume patches and said candidate channel regions are candidate channel volumes, the method comprising performing said dilation of sub-step c.1) three-dimensionally on the zone S volume patches.

17.- The method of claim 16, wherein said dilation is performed uniformly and perpendicularly to every point of the faces of each well-defined zone (S) volume patch:

- for the faces of the external perimeter of the zone S volume patch, in order to consider, at sub-step c.2), as candidate channel points (CCP), corresponding to voxels of a candidate junction volume, the external perimeter points that intersect the external perimeter of adjacent zone S volume patches, and/or

- for the faces of the internal perimeter of the zone S volume patch, in case the zone S volume patch has a hole (O) or cavity there within, in order to consider, at sub- step c.2), as candidate channel points (CCP), corresponding to voxels of a candidate hole volume, the internal perimeter points that intersect with other points of the same internal perimeter of the same zone S volume patch.

18.- The method of claim 17, wherein:

- said sub-step c.1) further comprises three-dimensionally eroding at least the already dilated perimeters of the zone S volume patches;

- comparing the zone S volume patches before being dilated with themselves once dilated and erosioned at least once; and

- if as a result of said comparison a difference is detected, said sub-step c.2) further comprises considering the points resulting from that difference and belonging to a zone BZ as candidate channel points (CCP) constituting:

- for the faces of the internal perimeter of the zone S volume patch: a potentially candidate hole volume passing through said zone S volume patch, wherein said intersection of internal perimeter points is indirectly detected as a result of said detected difference; or

- for the faces of the external perimeter of the zone S volume patch: a potentially candidate junction volume between at least two adjacent zone S volume patches.

19. - The method of claim 18, comprising performing a plurality of said dilations followed by a plurality of said erosions, and then perform said comparison.

20. - The method of claim 18, comprising performing a plurality of iterations including one dilation followed by one erosion, and perform said comparison after each of said iterations.

21. - The method of any of claims 18 to 20, wherein:

- said at least two different sub-volumes are at least three sub-volumes identified as: zone H, zone S and zone BZ;

- said step b) comprises generating zone H, zone S and zone BZ patches from, respectively, said at least three sub-volumes;

and wherein the method comprises determining that said potentially candidate hole volume or said potentially candidate junction volume corresponds to a candidate channel volume (CH) if at least two ends thereof contact zone H or zone BZ volume patches.

22. - The method of claim 21 , comprising applying a morphological skeletonization algorithm to said candidate channel volume (CH) to find the centre line of the channel.

23. - The method of any of the previous claims, wherein it is applied to a medical or veterinary field.

24. - The method of claim 23, wherein it is applied to the automatic detection of channels in internal organs.

25. - The method of claim 24, wherein said channels are volumetric data representing electrically conductive channels, in which case said zone S represents an electrically non-conductive zone, or volumetric data representing blood channels, in which case said zone S represents a low blood supply zone, or volumetric data representing tumour channels, in which case said zone S represents a tumour zone.

26. - The method of claim 25 when depending on any of claims 3, 7, 10, 11 , 21 or 22, wherein when said channels represent electrically conductive channels said zone H and zone S represent, respectively, electrically conductive and non-conductive zones, when the channels represent blood channels said zone H and zone S represent, respectively, healthy and low blood supply zones, and when the channels represent tumour channels said zone H and zone S represent, respectively, healthy and tumour zones.

27. - The method of claim 26, wherein said channels represent myocardium conducting channels (CC), said zone H, zone S and zone BZ representing, respectively, a healthy tissue zone (H), a scar tissue zone (S) and a border tissue zone (BZ) and said sub-volume isolated from said 3D volume is a myocardium 3D volume.

28. - The method of any of claims 1 to 22, wherein it is applied to geophysical exploration, to identify fluid channels, in which case the zone S represents a zone non containing or not susceptible of containing fluid.

29. - The method of claim 28 when depending on any of claims 3, 7, 10, 11 , 21 or 22, wherein said zone H and zone S represent, respectively, a zone containing fluid or susceptible of containing fluid and a zone non containing or not susceptible of containing fluid.

30.- Computer program product, which includes code instructions that when executed in a computer implement at least all the steps of the method of the invention according to any of the previous claims except steps a) and b).

31. - The computer program product of claim 30, which includes code instructions that when executed in a computer implement all the steps of the method of the invention according to any of claims 1 to 29.

32. - An EAM system, comprising:

- a catheter (C) having at least one electrode for acquiring values of an electrical parameter and/or of a parameter associated thereto, at different points of at least an endocardium and/or epicardium when travelling there through; and

- computing navigation (N) means in communication with said catheter (C) and comprising:

- locating means configured for collaborating with said catheter (C) to locate its positions along said travelling through the endocardium and/or epicardium; and

- reading means configured for collaborating with said catheter (C) to read the values acquired thereby;

wherein said computing navigation means (N) are configured and arranged for accessing said read values and located catheter positions, correlate them and build and store in memory means an EAM 3D volume therewith, and comprises a display (D) for displaying at least part of said EAM 3D volume, wherein the system is characterised in that the computing navigation means (N) implement the method of any of claims 5 to 15 when depending on claim 5 for identifying myocardium conducting channels (CC) on the EAM 3D polygonal mesh retrieved thereby at sub-step b.1), and for displaying on said display (D) at least the candidate channel region (CCR) identified at sub-step c.3).

33.- The EAM system of claim 32, wherein:

- said catheter (C) is an ablating catheter; and

- said computing navigation means (N) are configured for displaying in said display (D) the identified candidate channels region (CCR) together with at least part of said EAM 3D volume to visually guide an operator in the intraoperative use of said ablating catheter (C) travelling towards a myocardium conducting channel (CC) in order to ablate it.