The Variation of White Matter Connectome After Surgery Revealed Factors Affecting Supplementary Syndrome Recovery Time in Low-Grade Glioma Patients

Objective

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.

Methods

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.

Results

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).

Conclusions

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.