Introduction
GWs
Guidewire (GW) for endoscopic retrograde cholangiopancreatography (ERCP) was developed to maintain access to common bile duct (CBD) during therapeutic ERCP procedures such as pneumatic balloon dilatation, stent placement, device exchange, or guidance for stone removalHowever, technical success of selective biliary cannulation is also affected by other numerous factorsRecently, the use of 0.025-inch GWs has gradually increased. A 0.025-inch GW provides thinner diameter with similar core diameter compared with a 0.035-inch GW. It provides similar pushing ability to a 0.035-inch GW. However, it allows for an easier device exchange. In addition, it is easy to rotate a GW within a papillotome or bile duct. A thinner GW with a hydrophilic coating tip also has the ability to facilitate through severe stricturesHowever, the selection of an optimal GW might be difficult because numerous GWs from each manufacturer have different features. Clinical selection of GWs usually depends on the preference of the operator, availability, and/or the type of procedureIn this bench test and subsequent clinical trial, we analyzed basic mechanical properties of currently available 0.025-inch GWs. We also tried to evaluate a new 0.025-inch endoscopic GW with enhanced properties compared with conventional 0.025-inch GWs. This GW has a thin hydrophilic coating and high torque ability with a 0.025-inch stiff core to facilitate transpapillary biliary access. The purpose of this trial was to determine the rate of primary technical success and clinical outcomes without additional procedures for selective biliary access between a newly developed GW and a conventional GW based on the best mechanical performance among 0.025-inch GWs in a previous bench test.