Postoperative Nodal Efficiency of the Lesional-Hemispheric Hand Motor Area Increasing Potentially Facilitated Motor Recovery for SMA Syndrome.

Background: Supplementary motor area (SMA) syndrome commonly occurs after glioma resection and requires weeks to months of recovery.

Methods: Thirty-four glioma patients with SMA syndrome were reviewed and assigned to recovered and non-recovered groups based on whether their motor function recovered on postoperative day 7. To validate the association between variations in nodal properties and recovery time, neuro-navigated repetitive transcranial magnetic stimulation (nrTMS) was applied to stimulate potential nodes. Nine other patients (five nrTMS therapy and four sham-nrTMS treatments) with SMA syndrome with unrecovered motor functions on postoperation day 7 were prospectively enrolled.

Results: The potential nodes of the sensorimotor network related to recovery time were investigated using preoperative and postoperative resting-state functional magnetic resonance imaging, graph theoretical analysis, and dynamic functional connectome analysis. Nodal efficiency of the lesional-hemispheric upper limb region of BA 4 (A4ul_L) increased in the recovered group (preoperative, 0.472 ± 0.027; postoperative, 0.535 ± 0.020; p = 0.0006). The patients in the nrTMS therapy group quickly recovered (12.0 ± 1.6 days) compared to the sham-nrTMS group (29.5 ± 3.8 days, p = 0.0024). Variations in A4ul_L nodal efficiency was negatively correlated with recovery time (r = -0.841; p = 0.0046).

Conclusion: A4ul_L demonstrates enhanced postoperative nodal efficiency and shows therapeutic potential in SMA syndrome recovery, suggesting its viability as a therapeutic target.