What is foam sclerotherapy?
Invented around the same time as conventional sclerotherapy, foam sclerotherapy became popular only recently as a result of the use of ultrasound to control its distribution. Foam sclerotherapy is a technique where the sclerosant STS is mixed with air or a physiological gas in a syringe before being injected into your vein.
The result is a better contact with the vein walls. Instead of mixing with the blood like conventional sclerotherapy, the foam displaces the blood allowing direct contact with the walls. This technique provokes a spasm of the vein which helps the vein to contract. It is therefore more effective that liquid sclerotherapy.
For what type of varicose veins is foam sclerotherapy recommended?
There are now many studies done on foam sclerotherapy that determined it to be a “gold standard of care” for patients who have varicose veins between 1mm and 5mm in diameters.
But the long-term success on varicose veins larger than 5 mm (0.2 inches) is very low. Other treatments are in this case usually recommended.
One possible side effect in about 1/3 of patients is the appearance of brown lines or spots at the site of the injection. In most cases, they disappear within 3 to 6 months, but can be permanent about 5 percent of the time.
For more details, including info on the post-recovery duration and pain, watch the video below.
What is the cost of foam sclerotherapy?
Ultrasound-guided foam sclerotherapy is a lot less expensive than laser ablation. According to one research, the average price for foam sclerotherapy is $363.11. But, remember if you choose sclerotherapy, more than half the time an additional treatment is required. 
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