Fig 6.
Bar graphs of ratios of diffusion characteristics between the two sides of four structures in a patient with mild traumatic brain injury, using the immediate (A) and short-term follow-up (B) data. The quantities λ1, λ2, λ3, trace, FA, and LI correspond to that side of the structure that has the lowest anisotropy on the immediate image. The quantities λ1’, λ2’, λ3’, trace’, FA’, and LI’ correspond to the contralateral side of these structures. The four structures are external capsule (EC), anterior corpus callosum (ACC), posterior internal capsule (PIC), and anterior internal capsule (AIC). Each structure corresponds to a specific color. For the immediate data set, one side of the four structures has lower λ1, higher λ2 and λ3, and lower FA and LI than its contralateral homologous side. Also, trace is similar for both sides. For the follow-up data set, λ1, λ2, λ3, FA, and LI have become more similar between the two sides of each structure, therefore giving ratios that are closer to 1. The ratios of the trace have remained at values almost equal to 1. When looking at the absolute values of the diffusion characteristics, we notice that the ratios change because the side of each structure that had low anisotropy on the immediate dataset has higher anisotropy on the follow-up dataset.