Background: This study was aimed to establish a standard for internal jugular vein-J3 segment stenosis by jugular ultrasound and to investigate the impact of IJV-J3 segment stenosis on intracranial pressure and cerebral venous outflow.
Methods: 126 subjects who underwent jugular ultrasound from January 2015 to December 2020 were retrospectively recruited.
Results: The flow velocity of internal jugular vein -J3 segment was significantly lower in subjects with the trans-stenotic pressure ≥ 4 mmHg compared with those with trans-stenotic pressure <4 mmHg (p=0.0402). Flow velocity ≤ 27.5 cm/s suggested a trans-stenotic pressure ≥ 4 mmHg and was defined as internal jugular vein stenosis (p=0.0254). No difference was found between the intracranial pressure of internal jugular vein stenosis subjects and that of non-internal jugular vein stenosis subjects (p=0.7329). Results from linear regression also implied no correlation between internal jugular vein stenosis and intracranial pressure. However, the flow velocity in both left and right vertebral vein were significantly higher in internal jugular vein stenosis subjects as compared to normal controls (p=0.0056, p=0.0454).
Conclusion: Flow velocity ≤ 27.5 cm/s in internal jugular vein-J3 segment was defined as internal jugular vein stenosis. Internal jugular vein stenosis did not lead to intracranial hypertension, but resulted in cerebral venous outflow redistribution which presented as increased venous outflow in vertebral veins.