Background Tuberculous meningitis (TBM), a severe central nervous system infection, carries significant mortality and long-term neurological morbidity. While cognitive impairment is a common consequences of TBM, the contribution of glymphatic system dysfunction to this process remains poorly characterized. Objective To investigate glymphatic function in TBM patients using the diffusion tensor imaging (DTI)-derived along the perivascular space (ALPS) index and evaluate its utility in detecting and predicting mild cognitive impairment (MCI). Methods This cross-sectional study enrolled 62 TBM patients and 61 matched healthy controls (HCs). ALPS indices (left/right/whole-brain) were computed from DTI data. Cognitive function was assessed using MMSE, MoCA, TMT-A/B, CDT, VFT, DST, and SDMT. Group comparisons, partial correlation analyses, and ROC curve assessments were performed to examine relationships between glymphatic function and cognitive performance. Results TBM patients demonstrated significantly reduced ALPS indices (all p 0.05) and elevated diffusivity in projection (Dyproj) and association (Dzassoc) fiber regions compared to HCs. Within the TBM-MCI subgroup, left Dyproj/Dzassoc correlated negatively with CDT scores ( p 0.05), while ALPS indices showed: (1) negative correlations with TMT-A/B (left/whole-brain), (2) positive correlations with SDMT (right/whole-brain). MCI patients exhibited significantly lower right/whole-brain ALPS indices than non-MCI counterparts ( p 0.05), with ROC analysis demonstrating moderate predictive value (AUC = 0.70). Conclusion The DTI-ALPS index effectively captures glymphatic dysfunction in TBM and correlates with domain-specific cognitive deficits. As a non-invasive biomarker, it shows promise for early identification of TBM patients at risk for MCI, potentially facilitating timely intervention to mitigate cognitive decline.
Wang et al. (Fri,) studied this question.