|  | May-Thurner 
                              syndrome is compression of the left iliac vein by 
                              the artery crossing over it. This is normal anatomy, 
                              but in some people the artery presses on the vein 
                              enough to thicken the vein wall over time. This 
                              condition may occur in adults or children. In young 
                              people in whom swelling and/or discomfort with exercise 
                              are signals, the syndrome may not be complicated 
                              by thrombosis, and stenting alone may give excellent 
                              long-term results. These results are generally better 
                              compared with results in patients who have deep 
                              venous thrombosis before the compression is recognized. 
 From: http://www.goldstarwebs.com/Venous/medpro/handbook/hbk18c.html
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