Fig 1.
Images showing the four-step classification system of ETGBD failure stage.
Fluoroscopic and endoscopic images show the features of each category. Category 1: a. failure to identify the cystic duct (CD) orifice. b, c, d. Pillar applied: cholangioscopic assistance. Category 2: e. failure to advance the GW across the CD takeoff due to unfavorable angle of guidewire (GW). f, g, h. Pillar applied: cholangioscopic assistance. Category 3a: i. failure of GW access to the gallbladder (GB) due to CD obstruction (stone impaction). j, k. Pillar applied: 3-Fr microcatheter assistance. Category 3b: l. failure of GW access to the GB due to multiple tortuosities. m, n. Pillar applied: new flex-type GW. Category 4: o. failure of drainage stent insertion to the GB. p. Pillar applied: 3-Fr microcatheter assistance. q. Successful stent placement.
Fig 2.
Theoretical strategy of the four-step approach.
Diagrams show the pillars of assistance most useful for overcoming each potential failure category. Cholangioscopic assistance with SpyGlass DS (SG) can be helpful in troubleshooting to identify the CD orifice in Category 1 and to enable GW advancement across the CD takeoff in Category 2. The flex-type guidewire (Flex-GW) and 3-Fr microcatheter (3-Fr Micro) can be used in Category 3 to gain access to the GB in the case of CD obstruction (Category 3a) or multiple tortuosities (Category 3b). 3-Fr Micro can also be helpful in stent insertion to the GB in Category 4.
Table 1.
Patient characteristics.
Table 2.
Application of the three pillars of assistance.
Fig 3.
(a) Technical success of Classical ETGBD and Strategic ETGBD. Technical success is shown for each category. The overall success rate was significantly higher in the Strategic ETGBD group (63/65 patients, 96.9%) compared with the Classical ETGBD group (36/50 patients; 72.0%) (p = 0.0001). Solid line, Strategic ETGBD; broken line, Classical ETGBD. (b) Breakdown of techniques and pillars of assistance used at each category. The pillars of assistance applied at each category are shown. Of patients in the Strategic ETGBD group, SG was applied following failure in 13/65 (20.0%) at Category 1 and in 2/65 (3.1%) at Category 2. Failure occurred at Category 3a in 2/65 (3.1%) and was averted by application of 3-Fr Micro. Failure occurred at Category 3b in 19/65 (29.2%), which was followed by application of both Flex-GW and 3-Fr Micro. Failure occurred at Category 4 in 2/63 (3.2%) and was overcome by application of 3-Fr Micro. Conventional, ETGBD with conventional techniques; SG, cholangioscopic assistance; 3-Fr Micro, 3-Fr microcatheter assistance; Flex-GW, flex-type guidewire.
Table 3.
Complications.
Table 4.
Procedure time.