- Discussion:
    - venous malformations, although present at birth, often are not noticed until 1 year of age. They engorge when dependent, decompress when elevated, and enlarge with trauma, puberty, pregnancy, or use of oral contraceptives;
    - frequently confused with hemangiomas
    - present at birth
    - slow steady growth
    - do not involute
    - discrete and diffuse subtypes

- Diff Dx:
    - AV Malformations
    - Hemangioma

- Vascular testing
    - X-ray: calcification, adjacent bone changes
    - MRI: can distinguish between high flow (AVM) and low flow lesions (venous malformations);
    - Closed system venography
    - Radionuclide scanning;

- Treatment:
    - low-flow venous and lymphatic malformations can be treated either conservatively by compression garments or surgically by staged
              debulking, avoiding the need to return later to a previously scarred area;
    - surgery is complicated by bleeding or lymphatic leaks, hematoma or seroma, formation, skin necrosis, scarring, ulceration, contractures, and distention of channels in the same or adjacent areas

Hemangiomas, vascular malformations, and lymphovenous malformations: classification and methods of treatment.

Intra-articular Venous Malformations of the Knee