A 52-year-old male was referred from another hospital due to recurrent pancreatitis. The patient had suffered from intermittent abdominal pain for 2 months which radiated to the back. The amylase and lipase levels were 2,890 and 23,802 U/l, respectively, and from the transabdominal ultrasound examination from the other hospital, it was suspected that there might be a stone at the main pancreatic duct. The patient also had already undergone a previous abdominal CT scan at the same hospital, and it was not clear whether there was a stone or calcification at the pancreatic parenchyma without any significant dilatation of the duct. Because of unclear imaging findings, EUS was then performed, and it showed a stone inside the parenchyma at the head of the pancreas which was closed to the duct and caused the pancreatic duct compression. EUS also showed that there was lobulation with strands of the pancreatic head parenchyma, suggesting chronic pancreatitis. Then, the patient directly underwent ERCP, and the pancreatic duct could be cannulated even though there was a little bit of resistance when the guide wire was inserted. Based on the pancreatogram, there was no stone and duct dilatation. We decided to perform sphincterectomy and a 5-Fr pancreatic stent was placed. Four hours after ERCP, a repeated measuring of the amylase and lipase levels showed a significant decrease (640 and 584 U/l, respectively), and there was no more significant abdominal pain. After that, the patient was discharged, and there was no significant pain anymore during 1 month of follow-up, and the amylase and lipase levels were 34 and 35 U/l, respectively (fig. 1).

A 70-year-old female was referred from another hospital with recurrent colicky abdominal pain and a history of jaundice and red-colored urine. She had been diagnosed with nonviral chronic liver disease and idiopathic thrombocytopenic purpura many years ago. A previous transabdominal ultrasound examination only showed multiple cholelithiasis without any significant bile duct dilatation. The patient had also undergone magnetic resonance cholangiopancreatography (MRCP) when she had jaundice, which showed that there was a stone inside the bile duct. The amylase and lipase levels were 50 and 55 U/l, respectively. During follow-up before the patient was referred, the total bilirubin level had gradually decreased from 13.2 to 2.7 g/dl. The pain had also slightly improved. Then, we performed EUS to evaluate the bile duct and see whether the stone was still there or not, since it is not practical to repeat MRCP for follow-up, especially in the elderly, and in some cases, it is possible to have spontaneous passage of the stone. Our EUS examination revealed that there was still a stone inside the nondilated common bile duct (CBD) with multiple cholelithiasis. So we performed ERCP 1 day after that, and we could successfully extract the large CBD stone. However, when we performed EUS, there were also large esophageal varices, suggesting that the patient also had portal hypertension (fig. 2).

A 53-year-old male was referred with obstructive jaundice and dilated CBD due to an unknown cause based on transabdominal ultrasound. The patient had just undergone cardiac stenting about 1 year ago and was still on oral anticoagulants. An abdominal CT scan revealed that there was a pancreatic head mass with a diameter of 7 × 5 × 7 cm. Both CBD and pancreatic duct were dilated. It was also reported that there was no lymph node enlargement or liver metastasis. The CA 19-9 level was 392.61 U/ml. The amylase and lipase levels were 45 and 88 U/l, respectively, and the total bilirubin level was 7.97 mg/dl. We performed EUS in this patient, which showed total obstruction at the distal CBD, suggesting that it might be difficult to attempt ERCP cannulation. We also performed fine needle aspiration (FNA). The FNA procedure was successful, and there was no significant bleeding complication even though the patient was still on oral anticoagulants. Based on EUS examination, there was an enlargement of the lymph node, and it seemed that the tumor had infiltrated the portal vein. Then, the patient underwent PTBD, since the guide wire could not pass through the distal CBD for the rendezvous technique. The result of FNA from the mass at the pancreatic head was adenocarcinoma. We decided that this patient would undergo only palliative treatment (fig. 3).

A 15-year-old female came to our unit with recurrent abdominal pain which was located at the epigastrium. The amylase and lipase levels were 129 and 241 U/l, respectively. The highest amylase and lipase levels were 619 and 1,498 U/l, respectively. She had no jaundice, and a transabdominal ultrasound examination revealed that the pancreatic duct was dilated without any clear etiology. Since EUS could provide a better image of the pancreas than a CT scan or MRI, we decided to perform the EUS procedure. The EUS images showed pancreas divisum with chronic pancreatitis. The patient also underwent abdominal CT scan examination to confirm other possible abnormalities, which revealed pancreas divisum (fig. 4).

A 59-year-old male came to our unit due to obstructive jaundice with a total bilirubin level of 24.17 mg/dl. There was no clear etiology based on transabdominal ultrasound. It only showed dilated intra- and extrahepatic bile duct without any suspicion of mass either at the pancreatic head region or the distal CBD. The CA 19-9 level was normal. Then, the patient underwent ERCP for biliary stenting. After inserting a plastic stent, the clinical condition became better and the jaundice resolved (the total bilirubin level gradually decreased below the normal limit). EUS was performed several days after the patient had been discharged from the hospital. Our findings showed a mass at the distal CBD, and the FNA result showed only inflammation, and no malignant cells were found (fig. 5).