A forward-viewing endoscope may be a reasonable alternative in these circumstances, where afferent loop intubation would be easier, but papillary cannulation would be more challenging. The reversed papillary position makes it difficult for both side-viewing and forward-viewing endoscopes. The double-balloon enteroscopy technique uses two balloons to advance the forward-viewing endoscope through the intestine by alternating inflating and deflating balloons.
http://www.mednovahz.com/gastr....oenterology-instrume
