Risk factors of biliary intervention by imaging after living donor liver transplantation

Table 1 Baseline characteristics of the patients n (%)

Variable
Recipient age (yr)1	49.7 ± 10.1 (13-68)
Older age patients (> 65 yr)	6 (3.1)
Recipient sex (M/F)	138 (70.0)/58 (30.0)
Donor age (yr)1	34.0 ± 10.9 (16-64)
Older donor age (> 60 yr)	2 (1.0)
Donor sex (M/F)	114 (58.2)/82 (41.8)
Age difference (recipient age - donor age)	15.7 ± 14.4 (-22 to 42)
MELD score	17.4 ± 10.4 (2.1 to 58.1)
High score patients (> 35)	13 (6.6)
Cause
LC-B	51 (26.0)
LC-C	4 (2.0)
Alcohol	27 (13.8)
Hepatocellular carcinoma	80 (40.8)
Combined	5 (2.6)
Hepatitis A	9 (4.6)
Other (drug, autoimmune, unknown)	20 (10.2)
Total ischemic time	91.5 ± 16.0 (60-145)
Group 12	93.7 ± 17.9
Group 22	88.8 ± 15.1
Number of patients with biliary intervention	89 (45.4)
ERCP	38
PTBD	12
Both (ERCP and PTBD)	38
Re-operative intervention	0
Mean duration without biliary intervention (mo)	33.5 ± 28.6 (1-89)

¹Mean age;

²The groups were categorized according to the anastomosis site angle (median angle = 113.3°); group 1, angle > 113.3°; group 2, angle ≤ 113.3. MELD: Model for end-stage liver disease; ERCP: Endoscopic retrograde cholangiopancreatography; PTBD: Percutaneous transhepatic biliary drainage; LC: Liver cirrhosis.

Table 2 Clinical profiles of the patients analyzed n (%)

Variable	Number of patients
Using T-tube	13 (6.6)
Anastomosis method
Type 11	145 (74.0)
Type 22	51 (26.0)
MRI findings
Filling defect on MIP image	90 (45.9)
Diffuse bile duct dilatation	29 (14.8)
Biliary stricture	91 (46.4)
Biliary leakage	6 (3.1)
Biloma	13 (6.6)
Hematoma	10 (5.1)
Thrombus, infarct	3 (1.5)
Common bile duct stone	2 (1.0)

¹Type 1, single duct-to-duct anastomosis;

²Type 2, double duct-to-duct anastomosis including hepatoplasty. MRI: Magnetic resonance imaging; MIP: Maximum intensity projection.

Table 3 Patient characteristics and inter-observer agreement

	Radiologist 1	Radiologist 2	Inter-observer agreement
Anastomosis site angle (o)	112.9 (32.5-168.4)	109.2 (31-173)	0.896 (P < 0.001)
Length of filling defect (mm)	3.4 (0-33.9)	3.4 (0-33)	0.921 (P < 0.001)

Table 4 Cox regression model for factors predicting biliary intervention

Variable	Univariate		Multivariate
	Exp (B)	95%CI	Exp (B)	95%CI
Recipient age	1.01	0.99-1.04
Older age (> 65 yr)	2.10	0.85-5.20
Recipient sex	1.11	0.69-1.70
Donor age	1.00	0.98-1.02
Older donor age (> 60 yr)	0.92	0.13-6.51
Donor sex	0.84	0.55-1.28
Age difference1	1.01	0.99-1.02
MELD score2	1.00	0.99-1.02
High MELD score (> 35)2	0.97	0.42-2.22
Anastomosis method3
Type 2 vs 1	1.14	0.72-1.80
T-tube	0.98	0.43-2.24
MRI findings
Anastomosis site angle4
Group 2 vs group 14	0.42	0.27-0.65	0.48	0.30-0.75
Filling defect5	2.44	1.58-3.75	2.18	1.41-3.38
Length of filling defect5	1.04	1.01-1.06
Diffuse bile duct dilatation	1.59	0.93-2.70
Biliary stricture	1.03	0.68-1.56
Biliary leakage	2.49	1.01-6.14	2.52	1.02-6.20
Biloma	1.54	0.74-3.19
Hematoma	1.80	0.78-4.10
Thrombus, infarct	0.64	0.09-4.59

¹Recipient age-donor age;

²MELD, model for end-stage liver disease;

³Type 1, single duct-to-duct anastomosis; type 2, double duct-to-duct anastomosis;

⁴Checked on the three-dimensional image; the groups were categorized according to the anastomosis site angle (median angle = 113.3°); group 1, angle > 113.3°; group 2, angle ≤ 113.3°;

⁵Checked on the maximum intensity projection image. MRI: Magnetic resonance imaging.

Table 5 Biliary intervention rate by anastomosis site angle¹

Variable	Total number	Number of events	Rate of events	P value	Mean time interval to events (mo)	P value
Group 1	98	30	30.6%	P < 0.001	62.1 ± 4.1	P < 0.001
Group 2	98	59	60.2%		38.5 ± 4.2

¹The groups were categorized according to the anastomosis site angle (median angle = 113.3°); group 1, angle > 113.3°; group 2, angle ≤ 113.3°.