Figure 1.

T2-weighted brain magnetic resonance images and results of diffusion tensor tractography and transcranial magnetic stimulation in a 71-year-old female patient with an infarct in the left pontine base.

(A) T2-weighted MRI images (2 and 5 weeks after onset) showing an infarct in the left pontine base (red arrows). R: Right. (B) Diffusion tensor tractography (DTT) images of the corticospinal tract (CST). On both 2- and 5-week DTT images, the integrity of the left CST was preserved through the peri-infarct areas, however, the left CST was thickened on 5-week DTT images compared with that on 2-week DTT images (blank green arrow: thinning of the left CST on the 2-week DTT images, blue arrow: thickening of the left CST on the 5-week DTT image). R: Right; A: anterior. (C) Motor-evoked potentials (MEPs) elicited from the right abductor pollicis brevis (APB) muscle. In a 2-week transcranial magnetic stimulation (TMS) study, an MEP was elicited from the right APB muscle (latency: 28.5 ms; amplitude: 50 μV; excitatory threshold (ET): 100%). By contrast, the latency was shortened and the amplitude was increased in the 5-week TMS study (latency: 23.1 ms; amplitude: 350 μV; ET: 100 %). X-axis: Latency; Y-axis: amplitude.