May-Thurner syndrome is an anatomical factor associated with increased DVT formation, and is characterized by which of the following?
A. Narrowing of the left iliac vein at the site where the right iliac artery crosses over itAnatomic factors may also contribute to development of DVT. At the site where the right iliac artery crosses over the left iliac vein, the left iliac vein may become chronically narrowed predisposing to iliofemoral venous thrombosis, so-called MayThurner syndrome. External compression of major veins by masses of various types can also lead to venous thrombosis.