The gastric emptying is shorter after Duodenal Switch than after Sleeve Gastrectomy. This has been studied by having volunteers consume a known amount of measured food that contained trace amounts of medical nuclear markers. Using special imaging cameras, the amount of radiation collected in the stomach was measured over time. In the case of the Duodenal Switch patients, the emptying half time was 28 +/- 16 minutes, with the normal non-operated patient be at 91 +/- 20 minutes(i). The Gastric emptying after sleeve gastrectomy has been reported to be 38 +/- 19(ii) minutes and 57 +/-19(iii) minutes in two different studies.

(i) J. Hedberg et al., Gatric Emptying and Postprandial PYY resposnce after Biliopancreatic Diversion with Duodenal Switch. Obesity Surgery, (2001) 21:609-615.

(ii) Braghetto et al., Scintigraphic evaluation of gastric emptying in obese patients submitted to sleeve gastrectomy compared to normal subjects. Obesity Surgery, (2009); 19:1515-21

(iii) Bernstine et al. Gastric emptying is not affected by sleeve gastrectomy, without removal of the gastric antrum. Obesity Surgery, 2009;19:293-8.