Contralesional functional network reorganization of the insular cortex in diffuse low-grade glioma patients

Abstract

Diffuse low-grade gliomas (DLGGs) growing on the insular lobe induce contralesional hemispheric insular lobe compensation of damaged functioning by increasing cortical volumes. However, it remains unclear how functional networks are altered in patients with insular lobe DLGGs during functional compensation. Thirty-five patients with insular DLGGs were classified into the left (insL, n = 16) and right groups (insR, n = 19), and 33 healthy subjects were included in the control group. Resting state functional magnetic resonance imaging was used to generate functional connectivity (FC), and network topological properties were evaluated using graph theoretical analysis based on FC matrices. Network-based statistics were applied to compare differences in the FC matrices. A false discovery rate was applied to correct the topological properties. There was no difference in the FC of edges between the control and insL groups; however, the nodal shortest path length of the right insular lobe was significantly increased in the insL group compared to the control group. Additionally, FC was increased in the functional edges originating from the left insular lobe in the insR group compared to the control group. Moreover, there were no differences in topological properties between the insR and control groups. The contralesional insular lobe is crucial for network alterations. The detailed patterns of network alterations were different depending on the affected hemisphere. The observed network alterations might be associated with functional network reorganization and functional compensation.

Involvement of White Matter Language Tracts in Glioma: Clinical Implications, Operative Management, and Functional Recovery After Injury

“…Changes in language network connectivity in non-opercular regions have also been observed. For instance, using resting state fMRI, Fang et al (2021) found networks alterations involving the contralateral insular cortex in patients with low-grade glioma.…”

What Can Resting-State fMRI Data Analysis Explain about the Functional Brain Connectivity in Glioma Patients?

“…The dorsal attention network (DAN) appears to be affected by significant alterations, too; higher FC in frontal and occipital regions and lower in the subcallosum and the anterior cingulate cortex were found independently of the tumor characteristics and mutation status [32]. Another interesting aspect is the specific case of insular diffused low-grade gliomas: independently of the side of the tumor, the contralateral insula shows increased FC, especially towards the visual and sensorimotor networks [49], and higher communication efficiency [50] compared to HCs.…”

“…Being able to assess FC properties in more homogeneous groups of patients will improve the power of the rs-fMRI analysis to determine specific alterations associated with different characteristics of the tumors. [22][23][24][25][26][27][28][29][30]32,33,35,[38][39][40][43][44][45][46][47][49][50][51][52][53][54][55][56], grouped by field of application and reported in order of citation. This information was not available for the other 7 studies [31,34,36,37,41,42,48].…”

“…This information was not available for the other 7 studies [31,34,36,37,41,42,48]. reviewed for this work [22,24,25,27,[29][30][31][32][33][34][35][36][37][38][40][41][42][43][44][45][46][47][48][49][50][51][52][54][55][56], grouped by field of application, and reported in order of citation. This information was not available for the other 5 studies [23,26,28,39,53].…”

“…Figure 3. Number of patients (pt) with frontal, insular, parietal, and temporal glioma locations among the studies (N = 28) reviewed for this work[22][23][24][25][26][27][28][29][30]32,33,35,[38][39][40][43][44][45][46][47][49][50][51][52][53][54][55][56], grouped by field of application and reported in order of citation. This information was not available for the other 7 studies[31,34,36,37,41,42,48].…”