Unveiling Segmental Hemodynamic Heterogeneity in Internal Jugular Vein Stenosis: A Patient-Specific CFD Analysis

Hui Li¹Jian Dong²Chunxiao Lu³Xiao Xue⁴Lu Liu³Weiyue Zhang⁵Yifan Zhou⁶Huimin Jiang⁶Yali Wu⁷Beibei Mao⁷Guangtong Zhu⁷Haiyang Ma⁷Jian Chen⁸Zhiqiang Hu⁷Chen Zhou³Xunming JI^3*

• ¹Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
• ²Beijing Tiantan Hospital Affiliated to Capital Medical University, Beijing, China
• ³Xuanwu Hospital Capital Medical University Department of Neurology, Beijing, China
• ⁴Ophthalmology Department, Xuanwu Hospital, Beijing, China
• ⁵Beihang University, Beijing, China
• ⁶Capital Medical University, Beijing, China
• ⁷Beijing Shijitan Hospital Capital Medical University, Beijing, China
• ⁸Xuanwu Hospital Department of Neurosurgery, Beijing, China

Background and Purpose: While non-thrombotic internal jugular vein stenosis (IJVS), predominantly from extrinsic compression, is increasingly linked to cerebral venous outflow insufficiency, its segment-specific pathophysiology remains unclear. Given the distinct J1-J3 anatomy of the internal jugular vein (IJV), segment-based characterization may aid management. Case Presentation: We retrospectively analyzed five patients with non-thrombotic IJVS affecting different segments and etiologies. Clinical features, segment involvement, and lesion morphology were recorded. Patient-specific hemodynamics were modeled with computational fluid dynamics (CFD) from head-neck CT venography (CTV) using identical boundary conditions for cross-case comparison. All cases showed trans-stenotic pressure gradients that increased with stenosis severity. Elevated wall shear stress localized to the stenosis, with high-velocity jets within the narrowed segment and downstream vortices in post-stenotic regions. J3 stenoses from C1 transverse process and/or styloid compression improved after decompression, with better hemodynamic metrics, venous morphology, and symptoms. J1-J2 stenoses were mainly due to soft-tissue or arterial compression; feasible interventions were limited and conservative care yielded modest benefit. Conclusions: IJVS demonstrates segment-specific morphological and hemodynamic patterns. Patient-specific CFD derived from CTV quantitatively characterizes these abnormalities and may inform treatment selection and prognosis, although validation in larger cohorts is warranted.