Fig. 3.

Post-operative diffusion tractography to inform recovery potential in two patients with post-operative deficits. Left panel: A 42-year-old right handed male developed speech and motor deficits during resection of a radiologically transforming glioma in the medial frontal lobe. Speech recovered quickly over the first 3 days following surgery. Right hand function was absent immediately following surgery (0/5, MRC scale) and right leg function was significantly impaired (2/5). Post-operative diffusion tractography (DT) acquired 24 h after surgery showed preserved corticospinal (CST) fibers, supporting the diagnosis of a supplementary motor syndrome likely to recover. Hand function gradually returned on the 6th post-operative day; leg strength returned to normal by 1 month. Right panel: A 34-year-old right handed female developed sudden limb weakness. Immediate post-operative MRI identified an area of infarct affecting the corona radiata and body of the caudate nucleus. Post-operative DT demonstrated an asymmetrical CST, with fewer detected tracts adjacent to the infarct. Residual connections reaching the primary motor cortex, however, suggested some recovery potential. Hand function improved over the first 10 days after surgery, with additional gains in lower limb function with therapy which continued for 3 months post-surgery. However, she was still occasionally using a stick to walk