The Variation of White Matter Connectome After Surgery Revealed Factors Affecting Supplementary Syndrome Recovery...

Supplementary motor area (SMA) syndrome is a common complication after SMA glioma resection. The compensatory mechanism of the structural sensorimotor network (SMN) and the factors influencing the recovery time of SMA syndrome have not been investigated.

Pre- and postoperative diffusion tensor images of 42 low-grade glioma patients with SMA syndrome were processed to construct white matter connectomes. Patients were classified into fast and slow-recovery groups according to whether postoperative motor disorder recovers within 7 days. Fiber counts between nodes and graph theory topological properties were calculated. The shortest distance from the surgical region to the corticospinal tract (d_CST) and the upper limb region of Brodmann area 4 (A4ul) was measured to find correlations with recovery time. Cox regressions were conducted to identify factors associated with SMA syndrome recovery time. A general linear model was formed using significant factors in multivariate Cox analysis to predict recovery time.

Decrease of fiber number between lesioned-hemispheric A4ul and contralateral SMN is correlated with prolongation of recovery time. Compared with the slow-recovery group, a higher increase of nodal degree centrality and nodal efficiency of ipsilateral A4ul was found in the fast-recovery group (nodal efficiency: left pre-op: 0.182 ± 0.009, left post-op: 0.231 ± 0.008, p < 0.0001; right pre-op: 0.157 ± 0.021, right post-op: 0.195 ± 0.018, p = 0.0011); (nodal degree centrality: left pre-op: 1.985 ± 0.166; left post-op: 3.195 ± 0.230, p < 0.0001; right pre-op: 1.620 ± 0.389; right post-op: 2.411 ± 0.452, p = 0.0005). Multivariate Cox analysis indicated that the increase in nodal efficiency of A4ul and d_CST were protective factors for SMA syndrome recovery time. A significant negative correlation between the predict score and recovery time was found in the left lesion group (r = -0.756, p < 0.0001), and the same trend was found in the right lesion group (r = -0.531, p = 0.076).

This study revealed an increase in lesioned-hemispheric A4ul nodal efficiency and long d_CST as protective factors in SMA syndrome recovery. A decrease in the number of interhemispheric fibers connecting lesioned-hemispheric A4ul to nodes on the contralateral hemisphere was correlated with the long recovery time of SMA syndrome.