May-Thurner syndrome.

Three patients with long standing edema of the left leg were examined, and venography and hemodynamic studies were performed. All three patients had a "spur" (May-Thurner syndrome) of the left common iliac vein at the level of the crossover position of the right common iliac artery. Surgical exploration in two of these patients verified marked hypertrophy of the intima of the left common iliac vein that caused partial obstruction. Surgical repair resulted in great improvement. Anatomic findings at venography are characteristic of this syndrome. Hemodynamic pressure measurements are of ancillary help in confirming the diagnosis.