Vessel segmentation method

A method of segmenting a structure in a volume represented by a 3D digital representation, the method comprising the steps of:

• applying a region growing algorithm to the volume starting from a seed point to generate a final mask;
• evaluating the final mask to identify one or more regions including unconnected structures;
• when a region of the one or more regions including unconnected structures is found, identifying a new seed point in the region;
• applying the region growing algorithm to the new seed point resulting in a seed mask;
• and
• when the seed mask intersects with the final mask, creating a mask as a combination of the seed mask and the final mask, otherwise, applying a locally adaptive region growing iteration including iteratively performing the region growing algorithm to a next seed point to generate a new mask until the new mask intersects the final mask;
• wherein
• the locally adaptive region growing iteration includes:
• determining a first gray value distance between the next seed point and a low threshold value used to generate the seed mask and a second gray value distance between the next seed point and a high threshold value used to generate the seed mask;
• determining a minimum distance between the first and second gray value distances;
• when the minimum distance is lower than a preset threshold, enlarging a range between the low and the high threshold values so as to encompass the next seed point by replacing the low threshold value by a minimum of the low threshold value and the gray value of the next seed point and by replacing the high threshold value by a maximum of the high threshold and the gray value of the next seed point, otherwise replacing the next seed point by the new seed point;
• and
• applying the region growing algorithm to the volume starting from the new seed point to generate the new mask.