This 10 year-old male presented for assessment of leg length discrepancy and cutaneous “capillary” vascular malformation. The provisional diagnosis was Klippel-Trenaunay syndrome.
The axial fat-saturated T2 weighted MRI above shows dilated vascular structures in the right lower limb involving subcutaneous and multiple muscle compartments. Flow voids and pulsation artefact (particularly laterally) suggest a high flow component consistent with arteriovenous malformation. These findings favour Parkes Weber syndrome over Klippel-Trenaunay syndrome. There was no high output cardiac failure in this case.
Vascular malformations can be divided into high flow (predominantly AV malformations) and low flow (capillary, venous, lymphatic and mixed). Klippel-Trenaunay syndrome usually involves an entire limb and is of the mixed, slow-flow type. Parkes Weber syndrome also typically invloves an entire limb, but the malformation contains high-flow components.
Note that Parkes Weber is one man, of Sturge-Weber, Klippel-Trenaunay-Weber, Osler-Weber-Rendu, Pfeifer-Weber-Christian, and Weber-Cockayne fame.