Parasites and Biliary stones

Endoscopic retrograde cholangiopancreatography ١٢٣
The most important causes are:
No access to papilla:
Inability to advance the endoscope to the papilla may occur as a
result of esophageal or duodenal stricture. Reaching the papilla
endoscopically is rare in patients with a roux-en-Y gastrojejunostomy. A
transhepatically placed wire may be passed antegrade down the Roux
limb in this circumstance and grasped by the endoscopist to “pull” the
endoscope to the papilla (Tompkins, 1997).
Unsuccessful cannulation:
This can occasionally be difficult in cases of papillary stenosis or
Billroth II gastroenterosotmy (where the normal landmarks are 180º
opposite their usual position) or in the presence of a periampullary
diverticulum. Difficult cannulation can often be overcome with the use of
alternative techniques, such as wire-guided catheters or a papillotome
(Cuschieri, 2002). Also unsuccessful cannulation include persistence of
the same technique, trying a different technique, calling in a second staff,
or stopping the procedure, especially if the indication is not clear, if a
complication is apparent, or if the patient is not tolerating the procedure
well (Freeman et al., 1996).
Pre-cut (‘‘Access’’) papillotomy:
Pre-cut papillotomy refers to a variety of endoscopic techniques
used to gain access to the bile (or occasionally the pancreatic) duct. In
most patients, pre-cut papillotomy is followed by conventional
sphincterotomy, which permits completion of therapies, e.g., stone
extraction. However, pre-cut sphincterotomy sometimes is used to gain
access to the bile (or the pancreatic) duct for diagnostic cholangiography
(or pancreatography) alone. Thus, the alternative term ‘‘access