The weakened valves Allow blood pool inside the veins as an alternative to traveling to the heart. When blood pools from the veins, the veins turn into much larger, making them show beneath the skin. A blood clot, also known as thrombosis. A blood clot within the portal vein or https://www.sgvascularctr.com/varicose-vein-treatment-in-singapore-from-the-perspective-of-a-vascular-surgeon/