Utility of Routine Barium Studies After Adjustments of Laparoscopically Inserted Gastric Bands

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1 Gastrointestinal Imaging Original Research Swenson et al. Barium Studies After Gastric Band Adjustment Gastrointestinal Imaging Original Research Utility of Routine Barium Studies After Adjustments of Laparoscopically Inserted Gastric Bands David W. Swenson 1 Marc S. Levine 1 Stephen E. Rubesin 1 Noel N. Williams 2 Kristoffel Dumon 2 Swenson DW, Levine MS, Rubesin SE, Williams NN, Dumon K OBJECTIVE. The purposes of this study were to assess the utility of barium studies after adjustments of laparoscopically inserted gastric bands and to identify a threshold stomal diameter for predicting which bands should be loosened because of excessive tightening. MATERIALS AND METHODS. A total of 246 patients with laparoscopically inserted adjustable gastric bands underwent 668 routine band adjustments and barium studies after each adjustment. Forty-one barium studies of 30 patients with tight bands necessitating readjustment were compared with barium studies of 41 patients acting as controls. Barium studies of nine patients with obstructive symptoms before adjustment were reviewed to correlate stomal diameter with symptoms. The data were analyzed for a threshold stomal diameter below which obstructive symptoms were likely to develop. RESULTS. Mean stomal diameters were 2.9 mm for the group with tight bands after routine adjustment, 9.5 mm for the control group, and 5.1 mm for the group with obstructive symptoms. Thirty-nine of the 41 studies of tight bands after routine adjustment showed stomal diameters less than 6 mm. Seven of nine patients with obstructive symptoms and none of the 41 control patients had stomal diameters measuring less than 6 mm. Conversely, 40 of 41 control patients and two of nine patients with obstructive symptoms had stomal diameters greater than 6 mm. In none of the 41 cases in which the band was tight after routine adjustment was the stomal diameter greater than 6 mm. Thus, 6 mm was the threshold stomal diameter below which bands should be loosened. CONCLUSION. A stomal diameter of less than 6 mm after routine adjustment of a laparoscopically inserted gastric band can cause obstructive symptoms, so the band should be loosened in these patients. In contrast, a stomal diameter greater than 7 mm is unlikely to cause obstructive symptoms, so band loosening usually is not required. Keywords: bariatric surgery, barium study, fluoroscopy, laparoscopic adjustable gastric banding, obesity DOI: /AJR Received February 28, 2009; accepted after revision June 12, M. S. Levine and S. E. Rubesin are consultants for Bracco. 1 Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA Address correspondence to M. S. Levine (marc.levine@uphs.upenn.edu). 2 Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA. AJR 2010; 194: X/10/ American Roentgen Ray Society O besity has become a problem of epidemic proportions in the United States. The U.S. Centers for Disease Control and Prevention reported that in 2004, 66% of adults were overweight and 32% were obese [1]. Bariatric surgery is an effective means of achieving sustained weight loss, decreasing the risks of obesity-related comorbid conditions, and improving survival among obese persons [2]. Since its original performance by Belachew et al. in 1993 [3] and its approval for use in the United States in 2001 [2], laparoscopic adjustable gastric banding has become an increasingly popular form of bariatric surgery. This procedure entails laparoscopic placement of a band (Lap-Band System, Inamed) around the proximal portion of the stomach, producing a small gastric pouch (Fig. 1). The band is slowly tightened by incremental ad- ministration of saline solution through a subcutaneous port into the band, resulting in early satiety and weight loss. Studies [4 6] have shown that gastric banding produces weight loss comparable with that of Roux-en- Y gastric bypass and vertical banded gastroplasty but with fewer side effects. Early experience with laparoscopic adjustable gastric banding in the United States was characterized by frequent complications, such as band slippage, esophageal dilation, and stomal stenosis, necessitating surgical removal of the band and conversion to a Roux-en-Y gastric bypass [7 11]. These early failures were attributed to inexperience with laparoscopic techniques of band placement, inadequate follow-up, and excessive tightening of the band [9 11]. Patient outcome has since improved substantially as a result of improved preoperative screening AJR:194, January

2 Swenson et al. Fig. 1 Diagram shows laparoscopically placed adjustable gastric band around proximal portion of stomach, producing small gastric pouch. Introduction of saline solution into band through subcutaneous port increases luminal narrowing, resulting in early satiety and weight loss. If band is too tight, obstructive symptoms can develop. and careful postoperative follow-up with individual tailoring of band tightness [9 12]. Nevertheless, there is no consensus regarding the best approach for adjusting the bands. Some bariatric surgeons perform each band adjustment under fluoroscopic guidance in the radiology department, performing a barium study immediately afterward to assess the tightness of the band [8, 9, 13, 14]. If the band is thought to be too tight, some or all of the administered saline solution can be withdrawn from the band to prevent the development of obstructive symptoms. Other surgeons adjust the bands in their offices. The decision to add or withdraw saline solution from the band is based on the degree of weight loss and the presence of symptoms suggesting overinflation of the band, and follow-up barium studies are performed after band adjustment only if obstructive symptoms develop [9, 10, 15]. Our purposes were to assess the utility of routine barium studies after adjustments of laparoscopically inserted gastric bands and to identify specific radiographic criteria, including the stomal diameter of the band, for predicting which bands should be loosened because of excessive tightening at the time of adjustment. Materials and Methods Patient Sample A computerized search of the radiology and surgery databases at our university hospital revealed the cases of 246 patients with laparoscopically inserted gastric bands who underwent one or more adjustments and routine barium studies after each adjustment during a 3.7-year period from 2004 to These 246 patients underwent a total of 668 gastric band adjustments (mean, 2.7; range, 1 10) and barium studies immediately afterward for evaluation of band tightness. Review of the original radiology reports revealed that 45 of the 668 routine band adjustments (7%) were considered too tight on the basis of the barium study findings after the initial adjustment and that immediate readjustment (withdrawal of saline solution) was performed to loosen the band. The decision to readjust the band was based not on any established criteria for a tight band but on the joint opinion of the attending gastrointestinal radiologist and bariatric surgeon that some of the administered saline solution be immediately removed from the band because a small stomal diameter, proximal dilatation, or slow emptying of barium through the band was found during the initial barium study after administration of saline solution into the band. Images from 41 of the 45 barium studies obtained at readjustment were available for review. These 41 barium studies were performed on 30 patients with a mean of 1.4 studies (range, 1 6 studies) for each patient. Eight patients (27%) were men and 22 (73%) were women. Images from the barium studies of 41 randomly selected control patients who did not undergo band readjustment after administration of saline solution into the Tight band at index examination 30 patients 45 studies performed 41 studies available for review Band readjustment Fig. 2 Schema of patients in study. 246 patients with laparoscopically inserted adjustable gastric bands Index fluoroscopic examination (First follow-up study) band also were reviewed. Seventeen of the control patients were men (41%) and 24 were women (59%). A separate review of the surgical records of the 246 patients revealed that 10 of the patients (4%) had obstructive symptoms necessitating deflation of the bands. Images from the barium studies of nine of these 10 patients were available for review. Two patients were men (22%) and seven were women (78%). The overall schema of the three patients groups in the study is shown in Figure 2. Data on the patients and length of follow-up after band placement are presented in Table 1. Radiographic Examinations All adjustments of laparoscopically inserted gastric bands were performed in the radiology department under fluoroscopic guidance with digital fluoroscopic equipment (Sireskop SD, Siemens Healthcare) to localize the subcutaneous port and assist in positioning the needle. The surgeon inserted a 22-gauge deflected-tip needle into the port, aspirated and recorded the volume of saline solution present in the band, and refilled the band with a larger volume of saline solution according to manufacturer recommendations. A barium study was routinely performed after the adjustment for assessment of the tightness of the band. Images were obtained with the patient in the upright position during ingestion of a fixed 60-mL Asymptomatic 206 Patients 41 studies of 41 patients randomly selected for control group Not tight band at index examination 216 patients Clinical follow-up Obstructive symptoms 10 Patients 9 studies available for review Band readjustment 130 AJR:194, January 2010

3 Barium Studies After Gastric Band Adjustment TABLE 1: Clinical Data Age (y) Clinical Variable Patients With Tight Bands After Band Adjustment (n = 30) volume of high-density barium (E-Z-HD, E-Z- EM). On the basis of findings during assessment of the position and tightness of the band and ease of passage of barium through the stoma, a decision was made about readjusting the band by insertion of another needle into the port and withdrawal of a portion or all of the recently administered saline solution. The studies were performed by a resident, fellow, or one of two attending gastrointestinal radiologists. All images were interpreted by the attending radiologists. Control Patients (n = 41) Patients With Obstructive Symptoms (n = 9) All Gastric Band Patients (n = 246) Mean Minimum Maximum Follow-up period after band placement (d) Mean Minimum Maximum ,348 Weight loss after 3 mo of follow-up (lb) Mean 26.9 (12.2) 24.9 (11.3) 29.3 (13.3) 25.6 (11.6) Minimum 2 (0.9) 6 (2.7) 21 (9.5) 11 (5.0) Maximum 44 (20.0) 51 (23.1) 36 (16.3) 53 (24.0) Weight loss after 12 mo of follow-up (lb) Mean 45.0 (20.4) NA 50.8 (23.0) 38.3 (17.4) Minimum 5 (2.3) NA 41 (18.6) 6 (2.7) Maximum 75 (34.0) NA 64 (29.0) 75 (34.0) Note Values in parentheses are kilograms. NA = not applicable. Study Design The barium studies of 30 patients with tight bands after adjustment (41 studies), 41 control patients, and nine patients with obstructive symptoms before deflation of the band were reviewed retrospectively at a PACS workstation by two attending gastrointestinal radiologists. The reviewers were blinded to the clinical course after band adjustment. The reviewers were not, however, blinded to whether the patients had obstructive symptoms at the time of adjustment or whether the band was readjusted for being too tight because in those cases a second series of images was present for reassessment after the band had been loosened. The images were reviewed to determine stomal diameter, esophageal width, and gastric pouch width and height (Fig. 3). Stomal diameter was determined by measurement of the width of the lumen at the central portion of the band. Esophageal width was measured in the distal esophagus at its widest horizontal dimension above the gastroesophageal junction. When a discernible gastric pouch was identified above the band, pouch width was measured at its widest horizontal dimension, and pouch height was measured from the gastroesophageal junction to the proximal indentation of the band on the stomach. If the esophagus and gastric pouch were always collapsed on the available images, no measurements were obtained. If gastric pouch emptying time (defined as the time in seconds from ingestion of barium to passage of the barium below the band) was mentioned in the original radiology report, this time was recorded. Measurements were taken from barium studies obtained after the initial adjustment and after readjustment of bands that were too tight, from barium studies obtained after routine band adjustment for control patients, and from barium studies obtained before deflation of the band for patients with obstructive symptoms. All radiographic measurements were corrected for magnification. The known width (13 mm) of the radiopaque portion of the band was used as a reference standard. Stomal diameter was the main parameter for assessing the tightness of the band. The data were analyzed to determine whether there was a threshold stomal diameter below which obstructive symptoms were more likely to develop and necessitate readjustment of the gastric band. The data also were analyzed to determine whether there was a threshold stomal diameter above which obstructive symptoms were unlikely to occur and band readjustment was not needed. Two-sample Student s t tests (Excel 2003, Microsoft) were performed to determine whether there were statistically significant differences between the mean stomal diameter of the group with tight bands after adjustment and that of the control group and between the mean stomal diameter of the group with obstructive symptoms before band adjustment and that of the control group. Surgical files were reviewed to determine mean weight loss 3 months and 12 months after laparoscopic adjustable gastric banding. Our institutional Fig year-old man (control) with satisfactory result after routine adjustment of laparoscopically placed gastric band. Frontal spot fluoroscopic image obtained after ingestion of high-density barium shows only mild narrowing of lumen (short black arrows) where it traverses band (long black arrows), stomal diameter of 10 mm, no dilatation of distal esophagus (long white arrows), and emptying of barium into stomach below band. Short white arrows denote width of band used to determine radiographic magnification. Apart from expected early satiety, patient did not have obstructive symptoms during month after band adjustment. AJR:194, January

4 Swenson et al. Fig year-old woman with tight gastric band after routine adjustment that necessitated immediate readjustment of band. A, Frontal spot fluoroscopic image obtained after ingestion of high-density barium shows marked narrowing of lumen (short black arrows) where it traverses band (long black arrows), stomal diameter of only 3 mm, focal dilatation of distal esophagus (short white arrows), and emptying of small volume of barium into stomach below band. Long white arrow denotes gastric pouch above band. B, Frontal spot fluoroscopic image from repeat study with high-density barium after readjustment (partial deflation) of band shows considerably greater opening of lumen (short black arrows) where it traverses band (long black arrows), stomal diameter of 8 mm, less dilatation of distal esophagus (short white arrows), and greater emptying of barium into stomach below band. Long white arrow denotes gastric pouch above band. Apart from expected early satiety, this patient did not have obstructive symptoms during month after band adjustment. review board approved all aspects of this retrospective study and did not require informed consent from any patient whose radiographic images or medical records were included in our study. This investigation was compliant with HIPAA. Results Clinical Findings Data about weight loss in the 30 patients with tight bands after the initial adjustment of the laparoscopically inserted gastric band, the 41 control patients, and the nine patients with obstructive symptoms before band adjustment are presented in Table 1. Mean weight loss 12 months after band placement TABLE 2: Radiographic Data A was not determined for the control group because the mean follow-up period for this group was 94 days. The group with tight bands after adjustment and the control group had comparable weight loss, and the group with obstructive symptoms before band adjustment had slightly greater weight loss than the other two groups 3 months after surgery. Ten of the 246 patients (4%) who underwent laparoscopic adjustable gastric banding had obstructive symptoms (in addition to the expected early satiety) severe enough to warrant band deflation. These symptoms included dysphagia in three patients, regurgitation in three, nausea and vomiting in four, and B postprandial substernal or epigastric pain in two. Barium studies of nine of these patients were available for review. The symptoms resolved in all nine of the patients after the band was loosened. In contrast, none of the 30 patients with tight bands that were readjusted and only two of the 41 control patients had obstructive symptoms in the month after band adjustment. Neither of these patients needed deflation of the band for management of the symptoms. Radiographic Findings The 41 barium studies of the 30 patients with tight bands necessitating readjustment Variable After initial adjustment Studies of Patients With Tight Bands After Band Adjustment (n = 41) Control Patients (n = 41) Patients With Obstructive Symptoms (n = 9) No. of Cases With Data Mean Minimum Maximum No. of Cases With Data Mean Minimum Maximum No. of Cases With Data Mean Minimum Maximum Stomal diameter a a a 1 7 Esophageal width Pouch width Pouch height After readjustment Stomal diameter NA NA NA NA NA NA NA NA Esophageal width NA NA NA NA NA NA NA NA Pouch width NA NA NA NA NA NA NA NA Pouch height NA NA NA NA NA NA NA NA Note All measurements are in millimeters. NA = not applicable. a Statistically significant. 132 AJR:194, January 2010

5 Barium Studies After Gastric Band Adjustment showed a mean stomal diameter of 2.9 mm after the initial adjustment (Fig. 4A) and 8.1 mm after readjustment (partial deflation of the band) (Fig. 4B). The mean gastric pouch emptying time was 98.7 seconds after band adjustment and 30.5 seconds after readjustment. In the 41 control patients (Fig. 3), the mean stomal diameter was 9.5 mm, and TABLE 3: Median and SD of Stomal Diameter in Three Groups of Patients Statistic Patients With Tight Bands After Band Adjustment Control Patients Patients With Obstructive Symptoms 10th percentile Median SD Median Median + SD th percentile SD Note All values are in millimeters. Fig year-old woman with obstructive symptoms (dysphagia and postprandial vomiting) caused by tight band before band adjustment. Frontal spot fluoroscopic image obtained after ingestion of high-density barium shows marked narrowing of lumen (short black arrows) where it traverses band (long black arrows), stomal diameter of only 2 mm, focal dilatation of distal esophagus (short white arrows), dilated gastric pouch (long white arrow) above band, and emptying of relatively small volume of barium into stomach below band. Obstructive symptoms resolved after loosening of band. Luminal Diameter (mm) Patients With Tight Band After Adjustment Control Patients Patients With Obstructive Symptoms Fig. 6 Box plots show statistics on stomal diameters in three groups of patients. Asterisk indicates median lumen diameter for patient group; box, luminal diameter range from 1 SD above to 1 SD below median; vertical black line, luminal diameter range from 10th to 90th percentile. the mean gastric pouch emptying time was 36.1 seconds after routine adjustment. In the nine symptomatic patients, the mean stomal diameter was 5.1 mm before deflation of the band (Fig. 5). No gastric pouch emptying times were recorded for this group. Additional data about stomal diameter, esophageal width, pouch width, pouch height, and gastric pouch emptying time after the initial band adjustment and readjustment are presented in Table 2. The median and SD and box plots of the stomal diameters in the three groups are shown in Table 3 and Figure 6. In the comparison of the two groups of 41 studies, 39 of the 41 barium studies (95%) showing tight bands after adjustment revealed a stomal diameter less than 6 mm. None of the 41 control patients had a stomal diameter below this threshold. Conversely, 40 of the 41 control patients (98%) had a stomal diameter greater than 6 mm, whereas none of the 41 barium studies showing tight bands after adjustment revealed a stomal diameter above this threshold. Two of the patients with tight bands after adjustment and one of the control patients had a stomal diameter of 6 mm. Thus for routine band adjustments, 6 mm was the threshold stomal diameter below which band readjustment (i.e., loosening) was consistently performed and above which band readjustment was not performed. Seven of the nine patients (78%) with obstructive symptoms necessitating band deflation had a stomal diameter of 6 mm or less on barium studies, and the other two (22%) had a stomal diameter of 7 mm. Comparison of the three groups revealed that the mean stomal diameter was significantly smaller in the group with tight bands after adjustment than in the control group (2.9 mm versus 9.5 mm; p < ) and in the group with obstructive symptoms before band adjustment than in the control group (5.1 mm versus 9.5 mm; p < ). Discussion Laparoscopic adjustable gastric banding has been found to produce effective and sustained weight loss when combined with incremental tightening of the band [2, 5, 10 12]. If the band is too loose, patients are unlikely to experience substantial weight loss, and, conversely, if the band is too tight, weight loss may be associated with a variety of obstructive symptoms, including dysphagia, regurgitation, nausea and vomiting, and postprandial substernal or epigastric pain [11, 12, 15 17]. Nevertheless, we are not AJR:194, January

6 Swenson et al. aware of any consensus about the utility of barium studies for assessing gastric banding immediately after adjustment. Nor is there a consensus about optimal goals for stomal diameter to maximize weight loss and minimize complications. In the two U.S. Food and Drug Administration trials of the Lap-Band System (Inamed) (trial A started in 1995 [8, 9], trial B started in 1999 [9, 18]), patients with laparoscopically inserted gastric bands underwent periodic band adjustments with incremental administration of saline solution into the band followed by fluoroscopic barium studies to assess stomal diameter. The patients in these trials had high complication rates because of aggressive band tightening and excessive targeting of small stomal diameters on follow-up barium studies without adequate consideration of symptoms. In 2000, Wiesner et al. [19] sought to maximize weight loss after band placement with aggressive tightening of the band, using a target stomal diameter of only 3 4 mm on barium studies immediately after band adjustment. This approach resulted in complications in 28 of 98 patients (29%), including pouch dilation in seven, posterior band slippage in 11, gastric herniation in six, gastric volvulus in two, and band penetration in two. In 2001, DeMaria et al. [8] reported obstructive symptoms in 17 of 37 patients (46%) in whom the mean stomal diameter was 4.5 mm on barium examinations immediately after band readjustment. The results of these studies suggest that stomal diameters of 3 5 mm after adjustment of laparoscopically inserted gastric bands may be too tight and likely to be associated with more frequent obstructive symptoms and more serious complications. In our study, 39 of 41 barium studies (95%) showing tight bands after adjustment revealed a stomal diameter less than 6 mm (Fig. 4A), whereas none of the control patients had a stomal diameter below this threshold. Conversely, 40 of 41 control patients (98%) had a stomal diameter greater than 6 mm (Fig. 3), whereas none of the 41 barium studies showing tight bands after adjustment of laparoscopically inserted gastric bands revealed a stomal diameter above this threshold. At the same time, seven of nine patients (78%) with obstructive symptoms after placement of an adjustable gastric band had a stomal diameter of 6 mm or less (Fig. 5), and the other two had a stomal diameter of 7 mm. Finally, mean stomal diameter was significantly smaller in the group with tight bands after adjustment than in the control group (2.9 mm vs 9.5 mm; p < ) and in the group with obstructive symptoms than in the control group (5.1 mm vs 9.5 mm; p < ). These findings strongly suggest that patients with tight bands that were readjusted would likely have experienced obstructive symptoms had the band not been loosened. The group with tight bands after adjustment and the group with obstructive symptoms also had substantially greater esophageal width, gastric pouch width and height, and gastric pouch emptying times than the control patients. Our experience indicates that a stomal diameter less than 6 mm on fluoroscopic barium studies immediately after band adjustment (i.e., administration of saline solution) is likely to be associated with the development of obstructive symptoms. We therefore believe that an adjustable gastric band with a stomal diameter less than 6 mm on barium studies immediately after band adjustment should be loosened. Conversely, a stomal diameter greater than 7 mm on barium studies after band adjustment is unlikely to be associated with the development of obstructive symptoms, so we believe the band does not have to be loosened in these patients. Finally, a borderline stomal diameter of 6 7 mm may or may not be associated with the development of symptoms, so the decision to loosen the band should be based on ancillary radiographic findings, such as esophageal width, size of the gastric pouch, and gastric pouch emptying time. One potential concern is whether a stomal diameter greater than 7 mm will produce adequate weight loss. In our series, patients were successful in achieving weight loss 3 months after surgery regardless of stomal diameter, although we did not have adequate long-term follow-up data. In a study by Forsell [20], effective weight loss was obtained with the Swedish band 24 months after surgery with a stomal diameter as large as 12 mm. We therefore believe that a target stomal diameter greater than 7 mm on barium studies immediately after band adjustment can yield effective weight loss while decreasing obstructive symptoms in these patients. Our investigation had the inherent limitations of a retrospective study, including selection bias and interpretation bias. Our patient sample also was not randomized to undergo routine band adjustments with and without barium studies because all adjustments of gastric bands at our institution are followed immediately by barium studies. However, the impetus for this investigation was to establish whether our approach is justified given the greater utilization of resources for routine barium studies at the time of band adjustment. Our retrospective investigation also was not intended to correlate stomal diameter and weight loss, although our data suggest that laparoscopic adjustable gastric banding at our institution has produced reasonable weight loss without serious obstructive symptoms in most patients. Another limitation of our study was that the decision to readjust the band after initial administration of saline solution for band tightening was based not on established criteria but on the subjective opinion of the attending gastrointestinal radiologist and bariatric surgeon that the band was too tight because of a small stomal diameter, proximal dilatation, or slow emptying of barium through the band on the initial barium study after adjustment of the band. An argument could therefore be made that our study design produced inherent bias in which a significant difference was likely to be observed between stomal diameters of control patients and patients in whom the band was readjusted. Nevertheless, almost all patients with tight bands on the initial barium study after band adjustment had stomal diameters less than 6 mm. Similarly, seven of nine patients (78%) with obstructive symptoms necessitating band deflation had stomal diameters of 6 mm or less. We therefore believe that many of the patients with tight bands after the initial adjustment would have had obstructive symptoms had the band not been partially deflated immediately after the barium study that showed a small stomal diameter. A prospective investigation with a larger patient sample is needed to further elucidate the role of barium studies after adjustments of gastric bands. Our experience indicates that a routine fluoroscopic barium study after adjustment of a laparoscopically inserted gastric band yields useful diagnostic information that leads to readjustment of the band after approximately 7% of routine adjustments. On the basis of our findings, we believe a stomal diameter less than 6 mm after administration of saline solution into the band is likely to be associated with obstructive symptoms, so the band should be loosened. In contrast, a stomal diameter greater than 7 mm is unlikely to be associated with obstructive symptoms, so band loosening is usually not required. Finally, a stomal diameter of 6 7 mm should 134 AJR:194, January 2010

7 Barium Studies After Gastric Band Adjustment be viewed as borderline, and the decision to loosen the band should be based on the presence or absence of ancillary radiographic findings, such as increased esophageal diameter, pouch dilatation, and prolonged pouch emptying times. References 1. Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, JAMA 2006; 295: Provost DA. Laparoscopic adjustable gastric banding: an attractive option. Surg Clin North Am 2005; 85: Belachew M, Legrand MJ, Defechereux TH, Burtheret MP, Jaquet N. Laparoscopic adjustable silicone gastric banding in the treatment of morbid obesity: a preliminary report. Surg Endosc 1994; 8: Vella M, Galloway DJ. Laparoscopic adjustable gastric banding for severe obesity. Obes Surg 2003; 13: Chapman AE, Kiroff G, Game P, et al. Laparoscopic adjustable gastric banding in the treatment of obesity: a systematic literature review. Surgery 2004; 135: Maggard MA, Shugarman LR, Suttorp M, et al. Meta-analysis: surgical treatment of obesity. Ann Intern Med 2005; 142: DeMaria EJ. Laparoscopic adjustable silicone gastric banding. Surg Clin North Am 2001; 5: DeMaria EJ, Sugerman HJ, Meador JG, et al. High failure rate after laparoscopic adjustable silicone gastric banding for treatment of morbid obesity. Ann Surg 2001; 233: Ren CJ, Horgan S, Ponce J. US experience with the LAP-BAND system. Am J Surg 2002; 184:46S 50S 10. Fielding GA, Ren CJ. Laparoscopic adjustable band. Surg Clin North Am 2005; 85: DeMaria EJ, Jamal MK. Laparoscopic adjustable gastric banding: evolving clinical experience. Surg Clin North Am 2005; 85: Szold A, Abu-Abeid S. Laparoscopic adjustable silicone gastric banding for morbid obesity: results and complications in 715 patients. Surg Endosc 2002; 16: Cadiere GB, Himpens J, Vertruyen M, Germay O, Favretti F, Segato G. Laparoscopic gastroplasty (adjustable silicone gastric banding). Semin Laparosc Surg 2000; 7: Blachar A, Blank A, Gavert N, Metzer U, Fluser G, Abu-Abeid S. Laparoscopic adjustable gastric banding surgery for morbid obesity: imaging of normal anatomic features and postoperative gastrointestinal complications. AJR 2007; 188: Allen JW. Laparoscopic gastric band complications. Med Clin North Am 2007; 91: Spivak H, Favretti F. Avoiding postoperative complications with the LAP-BAND system. Am J Surg 2002; 184:31S 37S 17. Busetto L, Segato G, De Marchi F, et al. Postoperative management of laparoscopic gastric banding. Obes Surg 2003; 13: Rubenstein RB. Laparoscopic adjustable gastric banding at a U.S. center with up to 3-year followup. Obes Surg 2002; 12: Wiesner W, Schob O, Hauser RS, Hauser M. Adjustable laparoscopic gastric banding in patients with morbid obesity: radiographic management, results, and postoperative complications. Radiology 2000; 216: Forsell P. Pouch volume, stoma diameter and weight loss in Swedish adjustable gastric banding (SAGB). Obes Surg 1996; 6: AJR:194, January