At least some degree of hyperpigmentation (increased skin color) is common after sclerotherapy. This usually depends on the sclerosing technique and on the strength of the sclerosing solution. Hyperpigmentation generally resolves after 6-12 months. In rare instances, it persists longer than 1 year.

The hyperpigmented areas may be linear, following the course of the treated blood vessel (Figure 1). Or, they may be punctate, with dots of pigment reflecting the points of injection (Figure 2).

Figure 1 (a)

Figure 1 (b)

Figure 1. (a) Linear pigmentation following the course of the treated blood vessel. (b) Same leg, 8 weeks later. (Awaiting permission from Goldman MP, ed. Sclerotherapy Treatment of Varicose and Telangiectatic Leg Veins, 3rd ed. St. Louis: CV Mosby, 2001:192.)

Figure 2

Figure 2. Punctate (dotted) pigmentation 8 weeks after sclerotherapy. (Awaiting permission from Goldman MP. Adverse sequela of sclerotherapy treatment of varicose and telangiectatic leg veins. In Bergan JJ, Goldman MP, eds. Varicose Veins: Diagnosis and Treatment. St. Louis: Quality Medical Publishing, 1993.)

The pigmentation is caused by hemosiderin, which stains the deep layer of the skin (dermis). Hemosiderin is an iron-rich pigment resulting from a breakdown of red blood cells. The staining results from extravasation (escape) of red blood cells from the blood vessel. Treatment with graduated compression after hyperpigmentation appears to help, and laser treatment is successful in about 50% of patients.