Article
Postoperative cognitive and functional resting-state connectivity alterations in glioma patients
Postoperative Veränderungen von Kognition und funktioneller Ruhekonnektivität bei Gliompatienten
Search Medline for
Authors
Published: | May 25, 2022 |
---|
Outline
Text
Objective: Cognitive outcome predictions in glioma patients undergoing surgery are difficult in view of the diffusely infiltrating tumor nature and the widely distributed neural network representations of higher order functions. Previous studies suggest, that functional connectivity (FC) of tumor/peritumoral areas to the rest of the brain might be indicative for postoperative neurological outcome. We therefore investigated, in how far FC of tumor lesions to the rest of the brain, as well as extralesional (EL) FC may relate to cognitive outcome in glioma patients.
Methods: 18 glioma patients (11 IDH mutated) were compared to 18 healthy controls. All participants underwent resting-state-fMRI, as well as standardized neuropsychological testing. Subjects were examined pre- and 4.5 months postoperatively. Tumor lesions were segmented, and tumor-to-whole-brain (T-WB) FC, as well as extralesional whole-brain (EL-WB) connectivity estimates were determined based on a WB parcellation using the Brainnetome atlas. In addition, network-specific tumor-to-frontoparietal (T-FP) connectivity, as well as extralesional connectivity within the frontoparietal network (EL-FP) were determined accordingly, and partial correlations with test metrics analysed, as well as FC was compared between patients with better and worse cognitive outcome.
Results: Preoperatively, patients performed worse compared to healthy controls, which was significant with regard to verbal recall (p<.01). Postoperatively, cognitive performance further deteriorated in patients, albeit significantly only with regard to attention (p<.05). While neither T-FP, T-WB nor EL FC significantly correlated with task performance, patients with better postoperative attentional performance showed preoperatively lower T-FP connectivity (by trend, p<.052) compared to worse performing subjects. Moreover, patients with better attentional performance showed postoperatively significantly higher EL-FP connectivity in the contralesional hemisphere (p<.046) than worse performing subjects. Although EL-WB functional connectivity significantly decreased longitudinally (p<.01) in patients, mean EL-FP connectivity was maintained.
Conclusion: Extralesional FC longitudinally decreased in glioma patients, but frontoparietal connectivity was maintained. FC of tumor to task relevant extralesional brain regions may provide cognitive outcome estimates in some glioma patients, but needs as well to take into account functional (re)organization of extralesional brain regions.