"A few of my patients woke up in the middle of the night in a pool of blood," related Dr Lee. "The engorged veins probably burst due to the patient scratching or rubbing their legs against the bed sheet.

Dr Lee treats a wide range of vein-related problems. Many patients present themselves with large deep painful ulcers on their legs. Often, they have had these ulcers for some time, and dress them repeatedly, hoping that they will go away. But this type of ulcer will not heal unless the underlying problem is treated.

When everything is working well, the leg muscles pump and propel the blood towards the heart and the valves within the veins prevent the backflow. The vein starts to become varicose when these valves fail in this function. The backflow builds pressure within the vein, causing the veins to be bulgy and wiry. The leg starts to swell when the fluid from the veins is forced out into the surrounding tissues. As the sweelling becomes worse, the patient will start to feel heaviness and in the later stages develop pain in the legs.

Other serious complications may arise. Thrombophlebitis due to infection of the varicose vein. Lipodermatosclerosis, where the skin darkens and hardens, leading to an apprearance like an upside down champagne bottle. This is due to the red blood cells being forced out into the surrounding tissues. Eventually, some of these patients may develop venous ulcers.