Neurocognitive and Resting-State Functional Magnetic Resonance Imaging Changes in Patients With Diffuse Gliomas After Chemoradiation Therapy.

Abstract

This prospective observational study employed resting-state functional magnetic resonance imaging (rs-fMRI) to investigate network-level disturbances associated with neurocognitive function (NCF) changes in patients with gliomas following partial-brain radiation therapy (RT). Adult postoperative patients with either isocitrate dehydrogenase (IDH)-wild-type or IDH-mutant gliomas underwent computerized NCF testing and rs-fMRI at baseline and 6 months post-RT. rs-fMRI data were assessed using seed-based functional connectivity (FC). NCF changes were quantified by the percent change in age-normalized composite scores from baseline (ΔNCF_comp). Connectivity regression analysis assessed the association between network FC changes and NCF changes, using a split-sample approach with a 26-patient training set and a 6-patient validation set, iterated 200 times. Permutation tests evaluated the significance of network selection. Between September 2020 and December 2023, 43 patients were enrolled, with 32 completing both baseline and follow-up evaluations. The mean ΔNCF_comp was 2.9% (SD, 13.7%), with 38% experiencing a decline. Patients with IDH-mutant glioma had similar NCF changes compared with those with IDH-wild-type glioma. Intrahemispheric FC was similar between ipsilateral and contralateral hemispheres for 91% of patients at baseline, and 69% had similar intrahemispheric FC change posttreatment. FC changes accounted for a moderate fraction of variance in NCF changes (mean R², 0.301; SD, 0.249), with intranetwork FC of the parietal memory network (PMN-PMN, P = .001) and internetwork FC between the PMN and the visual network (PMN-VN, P = .002) as the most significant factors. Similar findings were obtained by sensitivity analyses using only the FC data from the hemisphere contralateral to the tumor. Post-RT rs-fMRI changes significantly reflected NCF decline, highlighting rs-fMRI as a promising imaging biomarker for neurocognitive decline after RT.