Clinical significance of different periampullary diverticulum classifications for endoscopic retrograde cholangiopancreatography cannulation

Table 3 Diagnosis, procedures, and post-procedure complications for different types of periampullary diverticulum in three classification systems

	Lobo classification, 1998			Boix classification, 2006				Li-Tanaka classification, 2012
	IDP	JPD	P value	I	II	III	P value	I	II	III	IV	P value
Total	65 (6.7)	902 (93.3)		306 (31.6)	556 (57.5)	105 (10.9)		65 (6.7)	655 (67.7)	105 (10.9)	142 (14.7)
Diameter of CBD (mm)	14 ± 4	14 ± 5	0.33	14 ± 5	15 ± 5	14 ± 6	0.37	14 ± 4	14 ± 5	14 ± 6	15 ± 5	0.56
Max. size of PAD (mm)	19 ± 8	13 ± 7	< 0.001	15 ± 8	13 ± 7	11 ± 7	< 0.001	19 ± 8	13 ± 7	11 ± 7	14 ± 9	< 0.001
≤ 10	11 (16.9)	531 (58.9)		146 (47.7)	325 (58.5)	71 (67.6)		11 (16.9)	384 (58.6)	71 (67.6)	76 (53.5)
10-20	38 (58.5)	287 (31.8)		118 (38.6)	182 (32.7)	25 (23.8)		38 (58.5)	217 (33.1)	25 (23.8)	45 (31.7)
> 20	16 (24.6)	84 (9.3)		42 (13.7)	49 (8.8)	9 (8.6)		16 (24.6)	54 (8.2)	9 (8.6)	21 (14.8)
CBD stones	51 (86.4)	765 (85.6)	0.85	262 (87.9)	470 (85.0)	84 (82.4)	0.31	51 (86.4)	559 (85.9)	84 (82.4)	122 (86.5)	0.79
Max diameter (mm)	13 ± 5	12 ± 7	0.23	12 ± 6	13 ± 7	12 ± 6	0.26	13 ± 5	12 ± 6	12 ± 6	13 ± 8	0.58
Multiple stone	19 (37.3)	353 (46.1)	0.22	115 (43.9)	224 (47.7)	33 (39.3)	0.29	19 (37.3)	258 (46.2)	33 (39.3)	62 (50.8)	0.24
Difficult stone removal	16 (31.4)	273 (35.7)	0.53	96 (36.6)	159 (33.8)	34 (40.5)	0.44	16 (31.4)	195 (34.9)	34 (40.5)	44 (36.1)	0.71
Mechanical lithotripsy	4 (6.2)	35 (3.9)	0.33	21 (6.9)	16 (2.9)	2 (1.9)	0.008	4 (6.2)	31 (4.7)	2 (1.9)	2 (1.4)	0.13
Retained stones	3 (5.9)	59 (7.7)	0.79	20 (7.6)	34 (7.2)	8 (9.5)	0.77	3 (5.9)	38 (6.8)	8 (9.5)	13 (10.7)	0.42
Guide wire in PD	6 (9.2)	86 (9.5)	0.94	30 (9.8)	48 (8.6)	14 (13.3)	0.32	6 (9.2)	66 (10.1)	14 (13.3)	6 (4.2)	0.08
ERPD	1 (1.5)	45 (5.0)	0.36	11 (3.6)	31 (5.6)	4 (3.8)	0.38	1 (1.5)	36 (5.5)	4 (3.8)	5 (3.5)	0.50
Operative time (min)	44 ± 21	41 ± 18	0.35	41 ± 18	41 ± 17	43 ± 21	0.81	44 ± 21	41 ± 17	43 ± 21	39 ± 17	0.48
Difficult cannulation	15 (23.1)	93 (10.3)	0.002	38 (12.4)	57 (10.3)	13 (12.4)	0.57	15 (23.1)	68 (10.4)	13 (12.4)	12 (8.5)	0.01
Successful cannulation	59 (90.8)	894 (99.1)	< 0.001	298 (97.4)	553 (99.5)a	102 (97.1)	0.02	59 (90.8)	651 (99.4)b	102 (97.1)	141 (99.3)b	< 0.001
Adverse events	8 (12.3)	79 (8.8)	0.33	26 (8.5)	48 (8.6)	13 (12.4)	0.44	8 (12.3)	57 (8.7)	13 (12.4)	9 (6.3)	0.30
Post-ERCP pancreatitis	5 (7.7)	53 (5.9)	0.58	19 (6.2)	29 (5.2)	10 (9.5)	0.23	5 (7.7)	38 (5.8)	10 (9.5)	5 (3.5)	0.24
Acute cholangitis	2 (3.1)	25 (2.8)	0.70	6 (2.0)	18 (3.2)	3 (2.9)	0.55	2 (3.1)	18 (2.8)	3 (2.9)	4 (2.8)	0.98
Perforation	1 (1.5)	1 (0.1)	0.13	1 (0.3)	1 (0.2)	0 (0.0)	1.00	1 (1.5)	1 (0.2)	0 (0.0)	0 (0.0)	0.20

For Boix classification, P = 0.017 with Bonferroni adjustment. For Li-Tanaka classification, P = 0.008 with Bonferroni adjustment. Successful cannulation: Boix: Type II vs type I,

^aP < 0.05; Li-Tanaka classification: Type II vs type I,

^bP < 0.01, type IV vs type I, ^bP < 0.01. CBD: Common bile duct; PAD: Periampullary diverticulum; ERCP: Endoscopic retrograde cho-langiopancreatography; ERPD: Endoscopic retrograde pancreatic drainage; PD: Pancreatic duct.