1[4]Daradkeh SS, Suwan Z, Abu-Khalaf M. Preoperative ultrasonography and predicton of technical difficulties during laparoscopic cholecystectomy. Word J Surg, 1998, 22:75-77.
2[5]Peters JH, Krailadsiri W, Incarbone R, et al. Reasons for conversion from laparoscopic to open cholecystectomy, in an urban teaching hospital. Am J Surg, 1994, 168:555-559.
3[6]Deziel DJ, Millikan KW, Economou SG, et al. Complications of laparoscopic cholecystectomy: a national survey of 4,292 hospitals and an analysis of 77,604 cases. Am J Surg, 1993,165:9-14.
