Varicose veins are the result of vein swelling due to poor venous circulation. Sclerotherapy is one treatment for varicose and spider veins. With sclerotherapy, a syringe is used to inject a solution into the veins. This solution creates irritation and scarring, causing the vein to close and be absorbed by the body. Sclerotherapy is noninvasive but can cause a number of complications.
Trapped Blood
Blood can become trapped in varicose veins that are treated using sclerotherapy. This can cause a small bump or raised area to persist after treatment. Both ends of the vein being closed leaves no pathway for trapped blood to escape. This complication usually goes away on its own after several weeks but it also can be treated by draining the trapped blood using a small needle.
Skin Changes
A number of changes to the skin can occur around the injection site, according to the Cleveland Clinic. In some cases, the area where the injection occurred becomes raised and red. This inflammation generally is not serious unless it occurs near the groin, where it can cause significant pain or nerve damage. In addition, sclerotherapy can cause hyperpigmentation of the skin around the injection site. This is due to iron deposited in the surrounding skin tissue, which is triggered by the immune response to the sclerotherapy solution. Hyperpigmentation often fades away after several months, but in some cases it is permanent.
Skin Ulcers
Ulceration of the skin is a potential complication of sclerotherapy, Medline Plus explains. Skin ulceration can occur when sclerotherapy solution leaks out of the treated veins. Because this solution is designed to irritate tissue, it can cause open sores around the vein. These sores can be painful and may become infected but generally pose no serious health risk if treated and kept clean.
Telangiectatic Matting
Telangiectatic matting is caused by the development of multiple small veins that extend away from the originally treated varicose vein. It is not known why sclerotherapy can result in the development of this network of small blood vessels. Telangiectatic matting can result in perpetual flushing or blushing of the affected area. In about 90 percent of patients, the network goes away on its own, but this complication is permanent for 10 percent of patients.
