Radiologic Evaluation of Patients Following Bariatric Surgery

Abstract

Overweight: body mass index (BMI) of 25 to 29 kg/m 2 ; • Obese: BMI of 30 to 39 kg/m 2 ; and • Morbidly obese: BMI of ≥ 40 kg/m 2 . The prevalence of obesity in the U.S. population was reported to have increased from 23% to 31% over the 20 years from 1982 to 2001. 1 Obesity is a risk for many acute and chronic health problems. 2 Approximately 280,000 annual deaths in the United States are due to obesity 2 ; thus, weight loss treatment is one of the most rapidly growing treatments in the United States. Numerous reports have shown that surgery is the most effective method for weight reduction. 2 Surgical ProceduresTwo types of bariatric surgical procedures have been developed: malabsorptive and restrictive. 2 Because of significant complications that accompanied the intestinal malabsorptive procedures, they are no longer used. One of the restrictive procedures, biliopancreatic diversion with duodenal switch, is not favored in the United States. 2 The two restrictive procedures favored are the Roux-en-Y gastric bypass procedure (RYGBP; Figure 1A) and the laparoscopic adjustable gastric banding procedure (LAGBP; Figure 1B). 2-4 Both types usually are performed laparoscopically and have a low morbidity and mortality compared with open procedures. 2 The major advantage of the RYGBP is its effectiveness in the morbidly obese patient with a BMI ≥ 50 kg/m 2 ; the LAGBP is not as effective in this cohort. The laparoscopic RYGBP also has been shown to produce more effective long-term weight loss than the LAGBP. 2 The advantages of the LAGBP are that it has a lower complication rate and the possibility remains of conversion to RYGBP at a later date.To perform a laparoscopic RYGBP, the surgeon creates a small (15-30 mL) gastric pouch, which is anastomosed to a retro-or antecolic and ante-or retrogastric Roux limb with either end-to-side or side-to-side anastomosis. Some authors report a lower complication rate with the antecolic, antegastric Roux limb. 3 When a side-to-side anastomosis to the gastric pouch is performed, a short, blind-ending jejunal stump is created; this stump should not be confused with a leak on postoperative gastrointestinal fluoroscopic studies. The enterostomy sites are stapled closed. The surgeon transects the jejunum approximately 30 cm from the ligament of Treitz and brings up to the gastric pouch the Roux limb, which should measure 75 to 150 cm (see Figure 1A). Longer limbs are used for massively obese patients. To avoid internal hernias, it is important for the surgeon to close the mesenteric defects in the jejunum and transverse colon. 3 With placement of the lap band for a LAGBP, the surgeon tries to place the band approximately 2 cm distal to the gastroesophageal junction, which produces a small gastric pouch, limiting food intake. However, due to patient anatomy, the lap band often is placed at the gastroesophageal junction. The access port is placed outside the peritoneal cavity in the subcutaneous fat. The tightness of the lap band is adjusted by varying the All faculty and staff in a positio...