Changes in functional connectivity are associated with functional independence in the early postoperative period following awake surgical resection of language-eloquent glioma.

Abstract

Background: Neurocognitive decline in patients with primary brain tumors is associated with alterations in the functional connectome and reduced independence in daily living. This study explores postoperative connectomic changes associated with functional independence outcomes in patients with eloquent glioma, and how these associations differ from neurocognitive-connetcomic relationships.

Methods: Fifteen patients with left perisylvian glioma underwent resting-state functional magnetic resonance imaging (fMRI) and neuropsychological evaluation within 2 weeks before and on average 1 month after resection. Functional independence was measured with the Physical Self-Maintenance Scale (PSMS) and the Instrumental Activities of Daily Living scale (IADL). Graph theoretical analysis quantified functional brain network properties.

Results: Postoperative need for assistance in at least 1 activity on the IADL increased in 80% of patients with Total scores significantly increasing at the group level (Mdn change = 4.0, P = .006). In contrast, need for assistance on the PSMS increased in less than 30% of patients and Total scores were unchanged. Connectomic changes in Local Efficiency, Clustering Coefficient, Path Length, and Betweenness Centrality showed significant associations with need for assistance on the IADL (ρ = 0.63 to.72, all P < .01) but few activities on the PSMS. Functional independence ratings were not associated with Karnofsky Performance Status, manual dexterity, tumor volume, or extent of resection.

Conclusions: Alterations in functional connectomic properties after eloquent glioma resection are associated with early postoperative need for assistance in instrumental activities. Changes in connectomics are also associated with cognitive outcome in this population, though properties most involved appear to differ from those underlying changes in independence.