Motivation Microtubules (MT) are filamentous cytoskeleton structures composed of tibulin protein subunits. Quantitative analysis of MT dynamics in live cell is necessary Growth and shortening events of MT by considering only the MT tip position is not a valid approximation if MT follow non-linear paths Reliable tracing of MT body is required

Challenges Intersecting and overlapping MT regions appear brighter due to additive florescence Typical binarization methods yields gaps

Tip Detection MT image is filtered by second derivative of Gaussian filter with different orientations to reveal curvilinear structures. Binary mask obtained by thresholding the filter response is then further skeletonized to have B(x,y) The candidate tip positions are marked by finding the line ends in B(x,y)

Methodology Use estimated tip positions as starting points – Apply fast marching to extract all possible paths starting with tip position and end points s.t. – Calculate the support of the path p – Select the path that maximizes the support

Results Results of the Geodesic Paths Results of the Proposed Algorithm