Patent ID: 6956961

Claim:
A method of identifying boundaries of biological cells, the method comprising: receiving a first image of a field of one or more cells in which a reference cell component of the one or more cells is identified by a reference cell component marker image parameter; receiving a second image of the field of one or more cells in which at least one cell shape-indicative marker of the one or more cells is identified by a cell shape-indicative marker image parameter; segmenting the reference cell component in the first image to generate a reference cell component mask of the first image; thresholding the cell shape-indicative marker in the second image to generate a digital representation of the second image comprising a cell shaped-indicative marker portion and a background portion; conceptually registering the reference cell component mask with the digital representation of the second image; applying a watershed algorithm to data provided by the registered reference cell component mask and digital representation of the second image such that idividual cell boundaries for the one or more cells in the field are identified (segmented cells); and extracting biologically-significant features comprising cell skeletal nodes and end points from the one or more segmented cells, the extraction following a skeletonization of the one or more segmented cells, the skeletonization comprising conducting an adjustable polygon shape approximation of the one or more segmented cells, wherein said adjustable polygon cell shape approximation comprises: (a) providing an image of the one or more segmented cells, the boundary of said one or more segmented cells having been ascertained by the segmentation; for each of one or more of the cells in the segmented cell image, (b) selecting two endpoints defining two parts of the boundary of at least one of said one or more cells; (c) for each part of said cell boundary, computing the distance from each point on the part of the cell boundary to a line between said endpoints; (d) determining a point d MAX on the portion of the boundary, said point d MAX being maximally distant from the line; (e) comparing the distance from the point d MAX to a predetermined threshold distance value, d TH ; (f) where d MAX is greater than d TH , discarding the line between the endpoints, using point d MAX as a new endpoint together with one of the original endpoints to separate the part into two new parts, and repeating (c) and following; and (g) where d MAX is less than d TH , using the line as a side of a polygon approximating the cell shape until a polygon approximating the shape of the cell is complete.