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Transpancreatic sphincterotomy
Another potential utility of a pancreatic access wire is to perform a wire-guided pancreatic sphincterotomy,
effectively also cutting the common ampullary muscle. The technique allows for a more focused cut than
the free-hand needle knife precut technique, probably reducing the risk of perforation, and frequently, the
biliary orifice can be visualized on the left edge of the cut crevice. Alternatively, an additional transverse
free-hand extension of the cut to the left can be performed. The method was spearheaded by the Helsinki
group, who showed that the method compared favorably to free-hand precut in a large retrospective multi-
[15]
center trial . More recently, a systematic review also concluded that the method offered a higher
cannulation success rate compared to the relevant alternatives, with a similar complication rate . A recent
[16]
randomized comparison found a comparable PEP risk, but a higher cannulation success rate (85% vs. 70%)
in transpancreatic sphincterotomy vs. double-wire technique . Long-term follow-up data are lacking at
[17]
this time.

Needle knife precut
Classic precut technique
Without PD wire access, utilizing a needle knife to gain access to the bile duct must be considered. In this
technique, the roof of the papilla is dissected layer by layer from the top of the mound, in the assumed
direction of the bile duct [Figure 1], until the whitish onion-skin appearance of the bile duct epithelium is
evident. The orifice can then usually be identified as a tiny nipple downstream, for subsequent cutting or
cannulation, usually with a guidewire . The method requires visual exposure of the tissues, so sufficiently
[18]
deep dissection is necessary, while avoiding transmural cut with duodenal perforation. The feasibility and
safety of the method depends on the size of the intraduodenal papillary portion, with small, flat or hidden
papillae leaving less space for cutting .
[2]
Data on precut success and safety vary widely, surely depending on technique and expertise, but also on
timing, sooner being safer. Initial statements on increased PEP risk have been somewhat countered by more
recent meta-analyses, particularly considering early precut vs. persistent cannulation attempts . Most
[19]
studies and guidelines state the need for expertise to safely perform biliary precut, but the training phase
obviously poses a concern. Precut does remain a potentially risky method and should not replace good
cannulation technique.

Needle knife fistulotomy
Suprapapillary fistulotomy is incision of the bile duct above the papillary orifice, onto the duodenal
protrusion of the bile duct, creating a direct fistular access to the bile duct independently of the papilla.
Subsequent maneuvers can then be performed through this orifice, or prograde extension of the fistula
across the papillary muscle can be made.

The method has the potential benefit of biliary access without touching the pancreatic orifice, thus reducing
[19]
the risk of PEP. Indeed, in the meta-analysis by Choudhary et al. , a distinct reduction in PEP was seen
with this method. However, its feasibility depends on anatomical factors and ideally a dilated bile duct down
toward the papilla, to increase the chance of successful bile duct puncture. Ampullary cancer represents a
special situation where the method can indeed be useful .
[20]

SPECIAL PROBLEMS
Periampullary diverticula
Duodenal diverticula are relatively common, particularly in elderly patients . Moreover, both advancing
[21]
age and the presence of the diverticulum promote the preferential growth of glucuronidase-producing
bacteria predisposing to the formation of gallstones . Periampullary diverticula with an extradiverticular
[22]