Background Internal jugular vein (IJV) stenosis has recently been recognized as a plausible source of symptom etiology in patients with cerebral venous outflow disorders (CVD). Diagnosis and determining surgical candidacy remains difficult due to a poor understanding of IJV physiology and positional symptom exacerbation often reported by these patients.

Methods A retrospective single-center chart review was conducted on adult patients who underwent diagnostic cerebral venography with rotational IJ venography from 2022 to 2024. Patients were divided into three groups for further analysis based on symptoms and diagnostic criteria: presumed jugular stenosis, near-healthy venous outflow, and idiopathic intracranial hypertension.

Results Eighty-nine patients were included in the study. Most commonly, ipsilateral rotation resulted in ipsilateral IJV stenosis and gradient development at C4–6 and contralateral stenosis and gradient appearance in the contralateral IJV at C1, with stenosis and gradient development in bilateral IJVs at C1–3 bilaterally during chin flexion. In all patients, 93.3% developed at least moderate dynamic stenosis of at least one IJV, more than two-thirds (69.7%) developed either severe or occlusive stenosis during rightward and leftward rotation, and 81.8% developed severe or occlusive stenosis with head flexion. Dynamic gradients of at least 4 mmHg were seen in 68.5% of patients, with gradients of at least 8 mmHg in 31.5% and at least 10 mmHg in 12.4%.

Conclusion This study is the first to document dynamic changes in IJV caliber and gradients in different head positions, offering insights into the complex nature of venous outflow and its impact on CVD.