Circumferential wall enhancement is associated with neutrophil-to-lymphocyte ratio in intracranial fusiform aneurysms

The biological significance of aneurysmal wall enhancement (AWE) on high-resolution vessel wall imaging (HR-VWI) and its relationship with peripheral inflammation in intracranial fusiform aneurysms (IFA) remain incompletely understood. This study aims to investigate the association between circumferential AWE (CAWE) and peripheral immunoinflammatory indices in IFA, and to compare these features in different subtypes of unruptured intracranial aneurysm (UIA).

In this retrospective study, 196 patients with UIA (38 fusiform, 158 saccular) were included. Peripheral blood samples collected at admission were used to calculate immunoinflammatory indices, including the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), systemic immune-inflammation index (SII), and platelet-lymphocyte ratio (PLR). AWE was assessed and categorized by blinded readers. Clinical characteristics and inflammatory markers were compared, and multivariate logistic regression was used to identify variables associated with CAWE in patients with IFA.

Patients with CAWE in the IFA cohort showed differences in peripheral blood-derived immunoinflammatory indices, with higher monocyte counts and NLR but a lower LMR (all P < 0.05). NLR remained associated with CAWE in a multivariable model (OR: 4.78, 95% CI: 1.21-18.92, P = 0.026). Compared to patients with ISA, the IFA group had a significantly higher rate of CAWE (P = 0.010) and exhibited differences in peripheral inflammatory profiles, characterized by elevated NLR (P = 0.038) and SII (P = 0.035), and decreased LMR (P = 0.028).

In this single-center retrospective study, CAWE in IFA was associated with differences in peripheral blood immunoinflammatory indices, including NLR. These findings should be interpreted as exploratory and require validation in larger prospective cohorts with longitudinal clinical follow-up.