Exploratory analysis of morphology-hemodynamics-perfusion relationships after intracranial stenting in severe intracranial atherosclerotic stenosis.

BACKGROUND: Intracranial artery stenting is widely used to treat severe intracranial atherosclerotic stenosis (ICAS). However, the relationships among post-stenting morphological remodeling, hemodynamic recovery, and perfusion imaging changes remain unclear. METHODS: This retrospective single-center study included 131 patients with severe ICAS (70-99%) who underwent intracranial stenting. Vascular morphology was assessed by digital subtraction angiography, hemodynamics were quantified using computational fluid dynamics, and CT perfusion was used to evaluate perfusion imaging changes. Associations among morphological, hemodynamic, and perfusion changes were analyzed using correlation, multivariable, and mediation analyses. RESULTS: A total of 131 patients were analyzed, including 108 with anterior circulation lesions (77 males; 71.3%; age 65.50 years [57.00-69.00]). Stenting significantly improved luminal morphology, hemodynamic parameters, and CT perfusion metrics (all p < 0.05). After adjustment for hemodynamic changes, morphological changes were no longer independently associated with perfusion imaging changes. Changes in pressure ratio (ΔPR) showed the strongest associations with reductions in Tmax-based perfusion-delay volume, nonlinear threshold effects, and a significant mediating effect on the association between morphological remodeling and improvement in perfusion-delay metrics. These associations were more evident in the anterior circulation than in the posterior circulation. CONCLUSION: Changes in translesional pressure ratio were more closely associated with post-stenting improvement in perfusion-delay metrics than geometric stenosis measures alone, suggesting that pressure ratio may serve as an intermediate hemodynamic marker linking anatomical remodeling with downstream perfusion imaging changes.