Automated Axon Tracking of 3D Confocal Laser Scanning ...

In comparison with the manual tracking results, the average deviation of the tracked axoncenterlines in the third dataset was found to be 1.81 pixels.In order to demonstrate the accuracy and robustness of the proposed method in this paper, thesegmentation results are compared with that of the repulsive snake model. In this algorithm, theuser has to define the initial boundaries and the centers of the axons in the first cross-sectionalimage of the dataset. The snake then iteratively evolves to the individual boundaries of the axonsby minimizing the energy functional. The algorithms were executed on a PC with a 1.6 GHzIntel Pentium processor and 1.2 Gigabytes of memory. Since the datasets mentioned earlier inthis section contain hundreds of cross-sectional images, one cross-section from each of thedatasets, where a significant difference in segmentation can be noticed, is used to compare thetwo algorithms. Figure 13 shows the results of the two algorithms in the first dataset.(a)(b)F igure 13 - Comparison of segmentation results in dataset one: (a) Repulsive Snake Model, and (b) Guided regiongrowing. The scale bars in the figures correspond to 2μm. The figures have been magnified for better visualization.30