Duodenal stasis is an undue retention of barium in the duodenum beyond the first portion, usually associated with dilatation of varying degree and with regurgitation, and is best observed by fluoroscopy or radiography. This condition has been frequently referred to in the literature as duodenal stasis, duodenal antiperistalsis, writhing duodenum, lagging of the duodenum, pendulum movement of the duodenum, and by other terms. Various authors have described a similar condition under the name of chronic duodenal ileus as a clinical entity being caused by mechanical processes, as adhesive bands, and traction on the ligament of Treitz. However, Case,1 in 1916, stated that duodenal stasis or chronic duodenal ileus due to such factors are rare, and this statement agrees with our observations. Duodenal stasis is not a clinical entity but a radiologic sign seen in various conditions such as cholecystitis, cholecystolithiasis and duodenal ulcer, as will be shown later.