Transient cerebellum-related network disruption characterizes postoperative cognitive changes after dominant...

Cognitive impairment following skull base meningioma resection remains poorly understood. This prospective study aimed to investigate the cognitive function alterations and resting-state fMRI (rs-fMRI) characteristics in patients undergoing extradural subtemporal approach meningioma resection.

This study enrolled 23 right-handed primary petroclival meningioma patients from June 2024 to November 2024. Participants underwent cognitive assessments combined with rs-fMRI scans at three time points (Time1: one day before surgery; Time2: one week after surgery; and Time3: three months after surgery), utilizing comprehensive test scales including the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Symbol Digit Modalities Test (SDMT) and Trail Making Test (TMT-A & TMT-B). Alterations of low-frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo), and functional connectivity (FC) were calculated. Patient demographic characteristics, medical records, and neuroimaging data were systematically collected and analyzed. Independent samples t-tests, Mann-Whitney U tests, Fisher's exact tests and paired samples t-tests were used in statistical analysis.

13 patients were in the non-dominant side (NDS) group, and 10 patients were in the dominant side (DS) group. There were no statistically significant differences in preoperative baseline (Time1) clinical characteristics and preoperative cognitive assessment outcomes between the two groups. Patients in the DS group showed marked decline in MMSE (mean Δ = -6.4 points, corrected p = 0.009), MoCA (mean Δ = -5.1 points, corrected p = 0.047), and SDMT scores (mean Δ = -17.8 points, corrected p = 0.003), along with prolonged TMT-A completion times (mean Δ =  + 32.7 s, corrected p = 0.017) at Time2. Six patients (60%) showed significant cognitive decline, while four patients (40%) maintained cognitive performance stable. Patients in the NDS group showed no significant postoperative cognitive decline. The rs-fMRI analysis revealed three characteristic alterations in cognition impaired patients: decreased ALFF in left thalamus, reduced ReHo in left middle temporal gyrus and lowered fALFF in left middle frontal gyrus (all p < 0.05). Significant weakening of functional connectivity between these regions and cerebellar networks were observed, and they show marked improvement in parallel with cognitive recovery at three months postoperatively.

Patients undergoing dominant hemisphere extradural subtemporal approach for petroclival meningioma resection showed a propensity for transient postoperative declines in verbal memory, orientation, and executive function. These cognitive changes were associated with reduced spontaneous cortical activity and attenuated functional connectivity within cerebello-cortical and cerebello-subcortical networks. Both cognitive performance and these neural alterations demonstrated improvement at the three-month postoperative follow-up, these preliminary observations await further validation in larger independent cohorts.