Abstract: An image analysis method characterizes cells based on the elongation. It analyzes an image of the cells and automatically identifies points or locations of high contrast (i.e., regions where the transition from intense signal to weak signal occurs abruptly, over a short distance). Groups of contiguous high contrast points collectively define a putative cell edge. Identified edges are then analyzed to determine whether they are elongated. In one example, edges with relatively low curvature are deemed elongated. The curvature analysis may be accomplished by calculating a shape descriptor for each edge (e.g., calculating the circular variance for each edge). One or more stages of the analysis may employ some degree of filtering, smoothing or other processing to remove certain artifacts in the image.