Recovery of an injured corticospinal tract and an injured corticoreticular pathway in a patient with intracerebral hemorrhage

The main function of the corticospinal tract (CST) is control of the distal musculature used for fine movements, in contrast, the corticoreticular pathway (CRP) innervates the proximal and axial musculature. We report on a patient with an intracerebral hemorrhage (ICH) who showed recovery of an injured CST and an injured CRP by diffusion tensor tractography (DTT). The patient, a 38-year-old man, presented with severe paralysis of the right upper and lower extremities due to a spontaneous ICH in the left corona radiata and basal ganglia. When he started rehabilitation at 3 weeks after onset, he showed more severe weakness in the proximal joints (shoulder and hip joints) than distal joints (hand and ankle joints). This proximal weakness improved rapidly in parallel with distal weakness over 3 weeks of rehabilitation. DTT performed at 3 and 6 weeks post-ICH revealed that a thin left CST observed at 3 weeks thickened at 6 weeks, and that a discontinuation of the left CRP at the midbrain level at 3 weeks was restored at 6 weeks. In addition, the track volumes of the left CST and CRP increased from 221 and 244 at 3 weeks to 725 and 625 at 6 weeks. In conclusion, we demonstrated the recovery of an injured CST and an injured CRP in a patient with ICH.