Transcranial Doppler Ultrasonography as a Biomarker for Cerebral Small Vessel Disease Severity: Correlation with MRI Findings

This study investigated the correlation between transcranial Doppler (TCD) parameters and cerebral small vessel disease (CSVD) severity in 87 patients (aged 40-85 years) diagnosed via MRI at a referral hospital in Iran. Using a cross-sectional design, we measured middle cerebral artery (MCA) and common carotid artery (CCA) hemodynamic indices, including pulsatility index (PI), flow velocities (PSV, EDV, MFV), and intima-media thickness (IMT). Results demonstrated significant associations between in-creased MCA-PI (1.12±0.29 vs 0.89±0.20, p<0.001), elevated CCA-IMT (0.08±0.01 vs 0.06±0.01mm, p=0.002), reduced flow velocities (PSV-MCA: 63.02±17.54 vs 72.16±14.37 cm/s, p=0.017), and severe white matter lesions (Fazekas score 3-6). Hypertension (77% vs 40%, p=0.003) and diabetes (45% vs 18%, p=0.012) were more prevalent in severe CSVD. While age strongly correlated with CSVD severity (62.4±9.8 vs 53.3±11.6 years, p<0.01), gender showed no significant association. These findings suggest TCD-derived PI and CCA-IMT may serve as reliable, non-invasive markers for CSVD severity, particularly valuable in resource-limited settings. The study supports TCD's potential for early CSVD detection but highlights the need for standardized diagnostic thresholds across diverse populations.