Klippel–Trenaunay syndrome and complex venous malformations: Should multimodality approach be standard of care?

Klippel-Trenaunay syndrome (KTS) is a complex vascular anomaly with a predominant venous component often coexisting with capillary and lymphatic malformations. KTS is usually unilateral with associated orthopedic anomalies involving the affected limb. These include limb hypertrophy or atrophy, fat hypertrophy, muscle atrophy, and scoliosis. The treatment can be challenging and frustrating due to the diffuse and infiltrative distribution of malformations involving multiple tissue compartments. The affected limb should be divided into regions, and each region should be treated separately and comprehensively. Within each region, venous malformations involving different tissue compartments may require different treatment modalities. Maximal elimination of intralesional blood flow within the vascular network should be aimed not only for where the lesion is treated but also for where the flow from adjoining compartments is eliminated or minimized. Endovenous laser ablation (EVLA), n-BCA glue embolization, and tumescent-assisted ultrasound-guided sclerotherapy (TUGS) are effective modalities to treat the venous component of KTS. The lymphatic component can be treated with doxycycline, bleomycin, ethanol, or OK-432 sclerotherapy.