To assess the findings on TCD in patients with tubercular meningitis on follow up on OPD visits/new events over 9 months of ATT.

Tuberculous meningitis (TBM) is a very severe form of tuberculosis and is complicated by cerebral vasculopathy, leading to infarction. Early detection of vascular involvement is crucial, yet conventional angiography as well as magnetic resonance imaging(MRI) is limited. Transcranial Doppler (TCD) is a non-invasive, bedside tool that can monitor cerebral hemodynamics and detect vasculopathy, but its diagnostic and prognostic role in TBM remains underexplored.

This was a prospective observational cohort study conducted at a tertiary care center in India between July 2023 and July 2025. Sixty-nine patients with TBM, were enrolled and followed upto 9 months. MRI with angiography and TCD ultrasonography of major intracranial vessels was performed, followed by examinations at 3 monthly intervals or on clinical change. TCD parameters- peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (MV), and pulsatility index (PI) were analyzed for association with vasculitis and infarction, compared with MRA findings, correlated with outcomes. Statistical analysis included t-tests, Mann Whitney U, univariate logistic regression, ROC curve analysis

Most infarcts were seen in the MCA territory. MCA: Vasculitis (42%) and infarcts (33%) were associated with significantly higher PSV and MV. ACA: Vasculitis showed no hemodynamic changes, but infarcts were marked by elevated PSV/EDV/MV and reduced PI PCA: PI was the sole reliable discriminator for vasculitis and infarction (AUC ~0.64-0.67). Longitudinal analysis showed rising PSV/MV with vasculitis and falling velocities with rising PI in infarcts. Hydrocephalus, MCA infarcts, and extensive basal disease were associated with poor outcomes

TCD is a valuable, non invasive bedside tool for detecting and monitoring TBM associated vasculopathy. Distinct hemodynamic signatures - elevated velocities in vasculitis and reduced velocities with increased PI in infarction allow differentiation of evolving vascular pathology.