A new classification of periampullary diverticulum: cannulation of papilla on the inner margins of the diverticulum (Type IIa) is more challenging

Table 1 Comparison between our classification method and traditional classification

location	completely inside	inner margin	outer margin	outside
new	type I	type II a	type II b	type III
traditional	type I	type II		type III

ISSN: 1471-230X