Common bile duct stones on multidetector computed tomography:Attenuation patterns and detectability

AIM:To investigate the attenuation patterns and detectability of common bile duct(CBD) stones by multidetector computed tomography(MDCT).METHODS:Between March 2010 and February 2012,191 patients with suspicion of CBD stones undergoing both MDCT and endoscopic retrograde cholangiopancreatography(ERCP) were enrolled and reviewed retrospectively.The attenuation patterns of CBD stones on MDCT were classified as heavily calcified,radiopaque,less radiopaque,or undetectable.The association between the attenuation patterns of CBD stones on MDCT and stone type consisting of pure cholesterol,mixed cholesterol,brown pigment,and black pigment and the factors related to the detectability of CBD stones by MDCT were evaluated.RESULTS:MDCT showed CBD stones in 111 of 130 patients in whom the CBD stones were demonstrated by ERCP with 85.4% sensitivity.The attenuation patterns of CBD stones on MDCT were heavily calcified 34(26%),radiopaque 31(24%),less radiopaque 46(35%),and undetectable 19(15%).The radiopacity of CBD stones differed significantly according to stone type(P < 0.001).From the receiver operating characteristic curve,stone size was useful for the determination of CBD stone by MDCT(area under curve 0.779,P < 0.001) and appropriate cut-off stone size on MDCT was 5 mm.The factors related to detectability of CBD stones on MDCT were age,stone type,and stone size on multivariate analysis(P < 0.05).CONCLUSION:The radiopacity of CBD stones on MDCT differed according to stone type.Stone type and stone size were related to the detectability by MDCT,and appropriate cut-off stone size was 5 mm.

Current diagnosis and treatment of benign biliary stricturesafter living donor liver transplantation

Despite advances in surgical techniques, benign biliary strictures after living donor liver transplantation(LDLT) remain a significant biliary complication and play an important role in graft and patient survival. Benign biliary strictures after transplantation are classified into anastomotic or non-anastomotic strictures. These two types differ in presentation, outcome, and response to therapy. The leading causes of biliary strictures include impaired blood supply, technical errors during surgery, and biliary anomalies. Because patients usually have non-specific symptoms, a high index of suspicion should be maintained. Magnetic resonance cholangiography has gained widespread acceptance as a reliable noninvasive tool for detecting biliary complications. Endoscopy has played an increasingly prominent role in the diagnosis and treatment of biliary strictures after LDLT. Endoscopic management in LDLT recipients may be more challenging than in deceased donor liver transplantation patients because of the complex nature of the duct-to-duct reconstruction. Repeated aggressive endoscopic treatment with dilation and the placement of multiple plastic stents is considered the first-line treatment for biliary strictures. Percutaneous and surgical treatments are now reserved for patients for whom endoscopic management fails and for those with multiple, inaccessible intrahepatic strictures or Roux-en-Y anastomoses. Recent advances in enteroscopy enable treatment, even in these latter cases. Direct cholangioscopy, another advanced form of endoscopy, allows direct visualization of the inner wall of the biliary tree and is expected to facilitate stenting or stone extraction. Rendezvous techniques can be a good option when the endoscopic approach to the biliary stricture is unfeasible. These developments have resulted in almost all patients being managed by the endoscopic approach.

Comparative study of rendezvous techniques in post-liver transplant biliary stricture

AIM： To investigate the usefulness of a new rendezvous technique for placing stents using the Kumpe （KMP） catheter in angulated or twisted biliary strictures. METHODS： The rendezvous technique was performed in patients with a biliary stricture after living donor liver transplantation （LDLT） who required the exchange of percutaneous transhepatic biliary drainage catheters for inside stents. The rendezvous technique was performed using a guidewire in 19 patients （guidewire group） and using a KMP catheter in another 19 （KMP catheter group）. We compared the two groups retrospectively. RESULTS： The baseline characteristics did not differ between the groups. The success rate for placing insidestents was 100% in both groups. A KMP catheter was easier to manipulate than a guidewire. The mean pro- cedure time in the KMP catheter group （1012 s, range： 301-2006 s） was shorter than that in the guidewire group （2037 s, range： 251-6758 s, P = 0.022）. The cu- mulative probabilities corresponding to the procedure time of the two groups were significantly different （P = 0.008）. The factors related to procedure time were the rendezvous technique method, the number of inside stents, the operator, and balloon dilation of the stric- ture （P 〈 0.05）. In a multivariate analysis, the rendez- vous technique method was the only significant factor related to procedure time （P = 0.010）. The procedural complications observed included one case of mild acute pancreatitis and one case of acute cholangitis in the guidewire group, and two cases of mild acute pancre- atitis in the KMP catheter group. CONCLUSION： The rendezvous technique involving use of the KIVlp catheter was a fast and safe method for placing inside stents in patients with LDLT biliary stric- ture that represents a viable alternative to the guide- wire rendezvous technique,

Undiagnosed Borrmann type Ⅱ gastric cancer due to necrosis and regenerative epithelium

Endoscopic biopsy is essential to the proper diagnosis and treatment of gastric cancer.Unfortunately,the results of endoscopic biopsy are not always the same as what is expected based on gross endoscopic findings.The results of endoscopic biopsy can be negative for malignancy in Borrmann typeⅣadvanced gastric cancer(AGCa)or gastric lymphoma.However,in the case of typeⅡAGCa,repeated biopsies negative for malignancy have not been reported.A 49-year-old male patient underwent esophagogastroduodenoscopy three times due to large gastric ulcer suspected to be Borrmann typeⅡcancer.However,three repeat endoscopic biopsies with multiple specimens showed necrosis and superficial regenerative epithelium without malignant findings.The patient underwent laparoscopic distal gastrectomy with D2 lymph node dissection.The surgical specimen revealed that the mucosal layer was completely replaced with regenerative epithelium without cancer cells.

Newly developed autoimmune cholangitis without relapse of autoimmune pancreatitis after discontinuing prednisolone

A 57-year-old man presented with a 2-wk history of painless jaundice and weight Iossl He had a large ill- defined enhancing mass-like lesion in the uncinate pro- cess of the pancreas with stricture of the distal common bile duct. Aspiration cytology of the pancreatic mass demonstrated inflammatory cells without evidence of malignancy. Total serum immunoglobulin G level was slightly elevated, but IgG4 level was normal. After the 2-wk 40 mg prednisolone trial, the patient＇s symptoms and bilirubin level improved significantly. A follow-up computed tomography （CT） scan showed a dramatic resolution of the pancreatic lesion. A low dose steroid was continued. After six months he self-discontinued prednisolone for 3 wk, and was presented with jaundice again. ACT scan showed newly developed intrahepatic biliary dilatation and marked concentric wall thickening of the common hepatic duct and the proximal common bile duct without pancreatic aggravation. The patient＇ s IgG4 level was elevated to 2.51 g/L. Prednisolone was started again, after which his serum bilirubin level became normal and the thickening of the bile duct was resolved. This case suggests that autoimmune pancre- atitis can progress to other organs that are not involved at the initial diagnosis, even with sustained pancreatic remission.

Duodenal obstruction following acute pancreatitis caused by a large duodenal diverticular bezoar

Bezoars are concretions of indigestible materials in the gastrointestinal tract. It generally develops in patients with previous gastric surgery or patients with delayed gastric emptying. Cases of periampullary duodenal divericular bezoar are rare. Clinical manifestations by a bezoar vary from no symptom to acute abdominal syndrome depending on the location of the bezoar. Biliary obstruction or acute pancreatitis caused by a bezoar has been rarely reported. Small bowel obstruction by a bezoar is also rare, but it is a complication that requires surgery. This is a case of acute pancreatitis and subsequent duodenal obstruction caused by a large duodenal bezoar migrating from a periampullary diverticulum to the duodenal lumen, which mimicked pancreatic abscess or microperforation on abdominal computerized tomography. The patient underwent surgical removal of the bezoar and recovered completely.