RESULTS In four of four animals, when the proximal stomach was occluded, 5-7 mm injuries of the posterolateral esopha- gus at the GE junction were easily detected with GIT. Gastric insufflation technique with proximal occlusion required minimal insufflation (mean <20 mm Hg), and, for every pump of the pressure ball, air bubbles were detected without manipulation of the stomach. When the pylorus alone was occluded, a higher pressure (mean 27 mm Hg) was required to sufficiently distend the stom- ach and reveal the injury. In the neutral position, pyloric occlusion alone did not consistently detect injuries. However, lateral retraction of the stomach allowed detec- tion of GE injuries. Small injuries (<3 mm) of the esoph- agus were difficult to visualize with pyloric occlusion alone but were consistently detectable with proximal stomach occlusion at pressures less than 20 mm Hg. Completion of Nissen fundoplication (two animals) did not impair detectability of GE junction dissection injuries. When the pylorus alone was occluded, the smallest detectable stomach perforation was a 16-gauge needle puncture at maximal gastric pressure (40-60 mm Hg). These pressures were generated in the open abdomen with manual manipulation of the stomach after maximal insufflation. Using laparoscopic techniques, GIT was unable to generate gastric pressures greater than 30 mm Hg. At lower pressures (20-30 mm Hg) linear, gastric injuries 2.5 mm in length were reliably detected with pyloric occlusion. With proximal stomach occlusion, 2.5 mm injuries of the GE junction and esophagus were eas- ily detected with gastric pressure of 30 mm Hg. DISCUSSION Despite the growing acceptance of laparoscopic Nissen fundoplication for the treatment of GERD, persistent questions remain regarding associated surgical morbidi- ty. Although much discussion has focused on dysphagia after LNF, this complication is most often self-limited and has minimal long-term implications. Persistent dyspha- gia requires endoscopie dilatation in only 3.5% of cases and operative revision in 0.9%.1 While it occurs much less commonly, gastroesophageal injury during laparo- scopic foregut surgery has greater implication for both patient and surgeon. The likelihood of injury is directly related to surgical experience. Yet, because there is a relatively small num- JSLS ber of patients who require LNF, many surgeons have limited experience with this advanced technique. This is unfortunate because the procedure clearly represents a higher level of laparoscopic complexity than cholecys- tectomy and may require a longer learning curve before the risks are appropriately minimized.4 Schauer et al2 found that the majority of injuries occurred during the surgeon's first ten cases. In this review,2 ten injuries occurred within the first ten procedures of 14 different surgeons. Two GE injuries occurred after the surgeon had performed more than 20 procedures. Conversely, when the results of only experienced surgeons are eval- uated only sporadic reports of injury are noted.4,5 Recent reviews2,3 have retrospectively evaluated the inci- dence and mechanism of GE injuries after LNF. In a mul- ticenter report of 2453 patients undergoing LNF, 1.1% had either esophageal or gastric perforation.1 Lowham et al3 reported 13 esophageal or gastric injuries out of a total of 1620 laparoscopic foregut operations (0.8%). This rate represents a higher incidence of GE injuries than that found with the dilatation of benign esophageal strictures (0.1%). Dilatation of esophageal strictures has been commonly considered the procedure at highest risk for perforation of the esophagus. The rate of injury com- monly reported (1%) is clearly higher than that found with "open" fundoplication. The review by Lowham et al3 focused on injuries from intraesophageal mechanisms. In their series, 11 occurred during bougie insertion and 2 during NGT placement. Five injuries were repaired using an "open" abdominal procedure, and in two patients thoracotomy was per- formed in a delayed setting. To avoid such injuries, the authors emphasize the importance of caudal and anteri- or retraction of the stomach during passage of the bougie. Furthermore, the crura should not be reapprox- imated prior to bougie placement because this displaces the esophagus anteriorly while the stomach lies posteri- or. This can easily result in anterior GE junction injury. Six of 13 perforations were related to this mechanism. Other important considerations include avoiding rapid insertion of the bougie, maintaining appropriate commu- nication with the team member inserting the bougie, using only experienced personnel for this part of the pro- cedure and not passing dilators in the presence of esophageal diverticula.3 Schauer et al2 evaluated GE injuries after LNF and focused on techniques of operative dissection. Among JSLS (1999)3:267-271 269