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Color Doppler Ultrasound Evaluation of Internal Jugular Vein Before Radical Neck Dissection

Objective: There is a great controversy about whether the internal jugular vein (IJV) should be retained during radical neck dissection. In this study, the right and left IJV under different body position were observed by color Doppler ultrasound, in order to provide a experimental
 basis for the preservation of IJV in neck dissections. Methods: A total of 40 patients with thyroid cancer undergoing radical neck dissection were examined in this study. The hemodynamic data such as section area, velocity, and volume of blood flow were measured by Doppler in supine
 and sitting position under quiet breath. Results: In supine position, the cross sectional area, the velocity and the blood flow volume in the right side were 58%, 23% and 91% more than left side respectively. The right side advantage, symmetrical, and left side advantage of IJV was
 in 65%, 25%, and 10% of patients. The blood flow of bilateral IJV was 74% of total cerebral outflow. The IJV predominate, balanced type, and no-IJV predominate cerebral venous drainage was in 73%, 23% and 5% of patients. In sitting position, the section area, the velocity and the blood flow
 volume in the right side were 29%, 35% and 56% more than left side respectively. The right side advantage, symmetrical, and left side advantage of IJV was in 45%, 45%, and 10% of patients. The blood flow of bilateral IJV was 23% of total cerebral outflow. The balanced type and no-IJV predominate
 cerebral venous drainage was in 23% and 78% of patients. Conclusions: There are side advantage of IJV. With quiet breathing, IJV is not the main pathway of cerebral venous drainage in sitting position. The preoperative ultrasound is useful to design the individualized surgical approach
 for the radical neck dissections.