Inclusion Criteria:  Presence of intra- or extrahepatic biliary stenosis, involving the main bile ducts: common hepatic duct, right and left hepatic ducts Presence of clinical jaundice and / or biological cholestasis (GGT> 3N) Absence of visible mass near the biliary stenosis after initial morphological assessment by abdominal CT scan, MRI with biliary sequences. Endoscopic ultrasound performed and not having allowed the acquisition of material of diagnostic interest by guided puncture of the lesion. No history of ERCP in the 6 months preceding inclusion and no biliary prosthesis (plastic or metal) in place at the time of inclusion Collegial validation of the need for a formal diagnosis of indeterminate biliary stenosis in order to guide therapeutic management Patients aged 18 to 85 Patient who gave his consent to participate in the study No contraindication to anesthesia (ASA 1, 2,3) Patient affiliated to a social security scheme (beneficiary or beneficiary) Absence of pregnancy and current contraception in women of childbearing age  Exclusion Criteria:  Presence of a manifest tissue mass in relation to the biliary stenosis on CT and / or MRI imaging. Very strong presumption of the etiological diagnosis of biliary stenosis given the history (history, background): i.e. liver surgery, cholecystectomy, autoimmunity History of ERCP and / or percutaneous biliary drainage in the 6 months preceding inclusion Presence of a plastic or metal biliary prosthesis in place at the time of inclusion History of cephalic duodeno-pancreatectomy or hepatico-jejunal anastomosis Non-passable stenosis of the main bile duct Severe coagulopathy, thrombocytopenia <75,000 G / L, treatment with clopidogrel cannot be interrupted even temporarily Anesthetic contraindication (ASA 4) Inability to obtain informed consent person deprived of liberty