Intraductal ultrasound substantiates diagnostics of bile duct strictures of uncertain etiology

Table 1 Baseline characteristics of the patient cohort

Baseline characteristics
Patients (n)	397
Age (yr), mean ± SE	61.43 ± 13
Sex (M/F)	210/187
IDUS performed (n)	397
Follow-up (mo), mean ± SE	39.7 ± 23.1
Follow-up range (mo)	12-100
Procedures (n)
Clinical follow-up	95
Surgery	264
Palliative therapy	32
Calculus extraction	6
Localization of stricture (CBD)
Proximal third	59
Middle third	46
Distal third	292
Final diagnosis (n)
Normal bile duct	25
Benign disease
Papillitis	30
Ampullary adenoma	18
Cholangitis	17
PSC	8
Mirizzi syndrome	7
Choledocholithiasis	14
Pancreatitis	59
Pseudocyst	4
Portal vein thrombosis	1
Papilloma of pancreatic duct	3
Choledochal cyst	1
Postoperative stenosis	1
Pancreatic cystadenoma	2
Caroli’s syndrome	1
Malignant disease
Cholangiocarcinoma	85
Pancreatic carcinoma	80
Ampullary carcinoma	26
Gallbladder carcinoma	9
Hepatocellular carcinoma	6

CBD: Common bile duct; PSC: Primary sclerosing cholangitis; M: Man; F: Female; IDUS: Intraductal ultrasound.