Classification of anatomical morphology of cystic duct and its association with gallstone

Table 1 Clinical and demographical characteristics of the study population

Variables	Study population (n = 300)
Sex, n (%)
Male	142 (47.3)
Female	158 (52.7)
Age, mean ± SD, years	48.1 ± 13.3
BMI, kg/m2, n (%)
< 24	133 (44.3)
≥ 24	167 (55.7)
Cholesterol, median (IQR), mmol/L	4.8 (4.1-5.4)
Triglyceride, median (IQR), mmol/L	1.6 (1.1-2.2)
Morphology of CD, n (%)
Linear	117 (39)
Tortuosity	183 (61)
Site of the CD insertion into the EHBD, n (%)
Right	265 (88.3)
Nonright	35 (11.7)
Length of CD, median (IQR), mm	23.4 (17.3-29.8)
< CHD, median (IQR), degrees	31.6 (21.8-45.7)
Intrahepatic biliary anatomy, n (%)
Typical	270 (66.7)
Atypical	30 (33.3)
Group, n (%)
Gallstone	200 (66.7)
Nongallstone	100 (33.3)

BMI: Body mass index; CD: Cystic duct; EHBD: Extrahepatic bile duct; < CHD: The angle between the common hepatic duct and the cystic duct.

Table 2 Univariate analysis and multivariate logistic regression analysis of the risk factors for gallstones

Variables	Univariate			Multivariate
	Gallstone group (n = 200)	Nongallstone group (n = 100)	P value	OR (95%CI)	P value
Sex, n (%)
Male	79 (39.5)	63 (63)	< 0.001
Female	121 (60.5)	37 (37)		3.32 (1.77-6.21)	< 0.001
Age, median (IQR), years	49.00 (38-59)	48 (41.00-56.8)	0.857
BMI, kg/m2, n (%)
< 24	76 (38)	57 (57)	0.002
≥ 24	124 (62)	43 (43)		2.51 (1.35-4.66)	0.004
Cholesterol, median (IQR), mmol/L	4.9 (4.3-5.4)	4.5 (3.8-5.3)	0.01
Triglyceride, median (IQR), mmol/L	1.67 (1.2-2.3)	1.5 (1.0-2.0)	0.025
Morphology of CD, n (%)
Linear	43 (21.5)	74 (74)	< 0.001
n-shaped	108 (54)	15 (15)		10.97 (5.22-23.07)	< 0.001
S-shaped	28 (14)	8 (8)		4.43 (1.64-11.95)	0.003
W-shaped	21 (10.5)	3 (3)		7.74 (1.88-31.78)	0.005
Site of the CD insertion into the EHBD, n (%)
Right	177 (88.5)	99 (99)	0.011
Left	16 (8)	1 (1)
Front	2 (1)	0 (0)
Back	5 (2.5)	0 (0)
Length of CD, median (IQR), mm	24.5 (19.6-32.4)	18.9 (13.5-27.1)	< 0.001
< CHD, median (IQR), degrees	31.0 (21.9-44.9)	33.4 (21.2-50.8)	0.576
Intrahepatic biliary anatomy, n (%)
Typical	178 (89)	92 (92)	0.414
Atypical	22 (11)	8 (8)

BMI: Body mass index; CD: Cystic duct; EHBD: Extrahepatic bile duct; < CHD: The angle between the common hepatic duct and the cystic duct.