A PSO-Powell Hybrid Method to Extract Fiber Orientations from ODF

Figure 4

Bar graph illustrating the angular deviations of fiber directions extracted from three-crossing-fiber ODFs constructed with QBI, CSA-QBI, and DOT using the methods of PSO-Powell, modified Powell, and decomposition. The ball-stick model directly extracts the directions from DWI raw signals. The azimuths and elevations of the synthetic three-crossing fibers are (0, 0), (1.22, 0), and (0.52, 1.05).