Two cases of hemiplegia at 5 years post-stroke onset showing changes in corticospinal and cortico-reticular pathways after 1 month of intensive rehabilitation including repetitive facilitative exercise.

Kisa T, Kato M, Sakai Y, Maguchi T, Uchida M, Kawasumi K, Ishihara H, Ohta M. Two cases of hemiplegia at 5 years post-stroke onset showing changes in corticospinal and cortico-reticular pathways after 1 month of intensive rehabilitation including repetitive facilitative exercise. Jpn J Compr Rehabil Sci 2025; 16: 60-67. Case reports have described the findings of diffusion tensor tractography (DTT) during the recovery phase of stroke hemiplegia but not during the chronic phase. We report here the cases of two patients with hemiplegia due to stroke, at 5 years post-onset, who underwent 1 month of intensive rehabilitation therapy including repetitive facilitative exercises and a phenol block, whose spasticity and paralysis improved. In both cases, significant changes were observed post-versus pre-DTT; the corticospinal tract (CST) was not visualized on the lesion side before treatment, but was visualized originating in M1 and extending downward after treatment. In the first case, over 5 years, transcallosal fibers (TCF) and transpontine fibers (TPF) extended from the contralateral side to the affected hemisphere, and the cortico-reticular pathway (CRP) of the DP descending motor pathways (DP) increased on both the affected and contralateral sides (particularly the former). However, after treatment, the CRP decreased on both sides. In the second case, the affected and contralateral sides. In the second case, the TCF became denser and the CRP on the contralateral side increased significantly. Previous case reports tracking changes in DTT were all within 1 year of hemiplegia onset. The two cases discussed here were 5 years post-stroke, and intensive rehabilitation not only improved upper limb and hand motor function in a short period but also produced imaging changes consistent with functional improvements on DTT. This is the first study to track changes in DTT before versus after intensive rehabilitation in old cases of stroke-induced hemiplegia. Most of the changes, such as the emergence of new CST patterns, increased CRP, and appearance of the TCF, were consistent with the working hypothesis derived from the accumulation of previous cases within 1 year of onset. However, in one case, the CRP decreased after treatment. This finding represents new insights not included in the working hypothesis and is discussed herein.