22-year-old female with lifelong, probable slow flow/venous malformation of the lower leg, increasing pain. There is proliferation of fatty tissue along the anteromedial aspect of the subcutaneous tissues of the leg. There is an extensive network of abnormal vasculature with variable degrees of enhancement surrounding an enlarged greater saphenous vein that begins approximately 6 cm below the knee joint and extends distally over a total length of 27 cm. The network of vessels appears to communicate with the posterior tibial vessels via a vessel that extends between the soleus and flexor digitorum longus muscle. There may also be communication with the distal peroneal vessels just above the ankle joint. More distally, the malformation extends deep to the tendons of the posterior tibialis and flexor digitorum longus, between the distal tibial metadiaphysis and flexor hallucis longus muscle, with fatty infiltration of the distal fibers of the posterior tibialis muscle which may represent a steal phenomenon. A component of this malformation also appears to extend within the anterolateral subcutaneous fat of the leg as well. The tibia and fibula appear normal.
Vascular malformation as described above.