What does "vascular sinus" mean?

In general, a vascular sinus refers to a venous sinus, which is an enlarged portion occurring within a vein. A detailed analysis is as follows:

Vein sinuses are typically formed by valve tissue structures within the veins. At the site of the valves, a bamboo-joint-like appearance commonly occurs along the course of the vein. The vascular segments with valve structures may dilate, preventing blood from flowing backward during venous return in either the lower or upper limbs. If no abnormalities are present, this represents a normal physiological variation and does not require special treatment. However, if there is significant dilation of the venous sinus accompanied by tortuosity, it may indicate damaged valve function leading to varicose veins.

After the onset of varicose veins, antiplatelet aggregation medications may be used under medical guidance, such as enteric-coated aspirin tablets, clopidogrel sulfate tablets, or warfarin sodium tablets, which help prevent thrombus formation.