[1] Univ Pittsburgh, Med Ctr, Dept Surg, UPMC Presbyterian Hosp F1281, 200 Lothrop St, Pittsburgh, PA 15213 USA
[2] Northshore Univ Hlth Syst, Dept Surg, 2650 Ridge Ave,Room 2539 Walgreen Bldg, Evanston, IL 60201 USA
[3] Univ Texas Southwestern Med Ctr Dallas, Dept Surg, 5323 Harry Hines Blvd,Off E-7102B, Dallas, TX 75390 USA
[4] West Virginia Univ, Dept Surg, POB 9238 Hlth Sci Ctr,One Med Ctr Dr, Morgantown, WV 26506 USA