The relationship between intracranial artery hemodynamics and subjective cognitive decline in patients with cerebral small vessel disease: a 4D flow study.

BACKGROUND: Recent studies link disrupted intracranial artery hemodynamics, including pulsatility index (PI), resistance index (RI), and wall shear stress (WSS), to neuroimaging features of cerebral small vessel disease (CSVD). Cognitive dysfunction is a key clinical manifestation of CSVD. Subjective cognitive decline (SCD), considered a pre-mild cognitive impairment stage, enables early identification and intervention to control cognitive decline. Nevertheless, scholarly investigation on SCD in CSVD and its underlying hemodynamic mechanisms remains limited.

OBJECTIVE: This study aims to utilize 4D flow magnetic resonance imaging (MRI) to explore the effects of intracranial artery hemodynamics on SCD in patients with CSVD.

METHODS: This study enrolled 40 patients with CSVD, comprising 20 individuals with SCD and 20 with normal cognition. SCD was evaluated according to established diagnostic criteria using the 9-item Subjective Cognitive Decline Questionnaire (SCD-Q9). Hemodynamic parameters, including PI-flow, PI-area, RI and WSS, were measured in nine major intracranial arteries via 4D flow MRI. Associations between these parameters and cognitive status were examined using logistic regression analysis.

RESULTS: Compared to the cognitively normal group, patients with CSVD and concomitant SCD showed lower arterial elasticity at the C7 segment and the basilar artery (BA), and lower WSS at the C2 segment. Logistic regression analysis further identified abnormal RI-BA was independently associated with SCD in the CSVD cohort.

CONCLUSION: Altered intracranial artery hemodynamics in patients with CSVD are associated with the presence of SCD. These findings offer mechanistic insight into early cognitive impairment in CSVD and suggest that hemodynamic abnormalities may serve as potential indicators of early cognitive dysfunction in this population.