Risk factors of post-ERCP pancreatitis at a tertiary referral center in Japan.

PURPOSE: Endoscopic retrograde cholangiopancreatography (ERCP) has played a major role in the diagnosis of biliary and pancreatic diseases. The prevalence and mortality rate of post-ERCP pancreatitis (PEP) remains a serious issue that needs to be resolved. Here, we report the first ERCP study that was conducted at a high-volume center of an educational institution in Japan. METHODS: This study investigated patients with suspected biliary and pancreatic diseases who had undergone ERCP between April 2006 and June 2009. We created a database and analyzed preoperative and postoperative data. Patients who had undergone surgery and those with a history of undergoing duodenal papilla treatment were excluded. RESULTS: Mild (n=62) or moderate (n=3) pancreatitis was present in 65 cases (6.21%; 36 men and 29 women). A univariate analysis identified age under 50 years (P=0.01), pancreatography (P<0.001), and biliary stent placement (P<0.001). A Multivariate analysis was performed for evaluating the risk factors associated with PEP. This analysis identified age of the patients under 50 years [P=0.003; odds ratio (OR), 0.37; 95% confidence interval (CI), 0.19-0.71], endoscopic papillary balloon dilation (P=0.012; OR, 4.69; 95% CI, 1.41-15.54), pancreatography (P<0.001; OR, 5.55; 95% CI, 2.98-10.33), and plastic stent placement (P<0.001; OR, 3.77; 95% CI, 2.17-6.54). Descriptive statistics showed that only pancreatography was associated with PEP. An additional sphincterotomy did not increase the risk of PEP (P=0.306; OR, 2.03; 95% CI, 0.52-7.84), and even adjusted for pancreatography. CONCLUSIONS: We changed the size of the stent to 7-Fr. In the future, we plan to repeat the same study with a higher number of cases.

Is it safe to perform endoscopic band ligation for the duodenum? A pilot study in ex vivo porcine models.

AIM: In the digestive tract, endoscopic band ligation (EBL) has been routinely used for the treatment of variceal bleeding and superficial malignancies. In recent years, endoscopic treatments for duodenal varices, adenoma, and cancer have also actively incorporated EBL. Although there have been a number of reports on the risks associated with the use of EBL in the esophagus, stomach, and colon, few studies have focused on EBL in the duodenum. We performed EBL procedures to evaluate the risks associated with the use of EBL in the duodenum. MATERIAL AND METHODS: Overall, EBLs were performed at nine sites in duodenum sampled from a pig immediately after sacrifice. Submucosal saline injections were placed in three of the nine studied sites. RESULTS: Regardless of saline injection, the full thickness of the duodenal wall was ligated in all attempts. CONCLUSIONS: Routine EBL is not recommended in the duodenum because the risk of perforation is unacceptably high.

How do we select an endoscopic treatment for esophageal varices on the basis of hemodynamic analysis using color Doppler endoscopic ultrasonography.

We investigated the hemodynamics of the left gastric vein (LGV) and its association with variceal recurrence using color Doppler endoscopic ultrasonography (CD-EUS). The long-term results of our technique known as combined ligation and sclerotherapy showed that the risk of variceal recurrence decreased after long-term follow-up with timely repeated therapies. On the basis of the hemodynamic background of these results, it was suggested that the posterior branch of the LGV could have developed as an extravariceal shunt, whereas the anterior branch, which directly feeds varices, seemed to disappear through long-term follow-up with repeated treatments. In the study comparing CD-EUS findings between patients with and without variceal recurrence, dominance between anterior and posterior branches and the hepatofugal flow velocity of the LGV were suggested to be important factors contributing to variceal recurrence. We consider that these patients may require more intense therapy, such as the mucofibrosing technique or a technique to obliterate both the varices and their donor vessels.

A comparison of electronic radial and curvilinear endoscopic ultrasonography in the detection of pancreatic malignant tumor.

OBJECTIVE: There is no comparative study of electronic radial endoscopic ultrasonography (ER-EUS) and electronic curvilinear EUS (EC-EUS). The aim of this study was to compare the accuracy of ER-EUS and EC-EUS for detecting pancreatic malignancies. METHODS: This was a retrospective review of the patients who had EUS assessment from September 2008 to December 2011 for suspicious pancreatic tumors. Sensitivity, specificity, and area under the ROC curve to detect pancreatic malignancies were calculated and compared between the ER-EUS and EC-EUS cohort. The final diagnosis of pancreatic malignancy was based on pathology, or the consensus of patient's clinical course and multimodal imaging tests. RESULTS: Two hundred twenty-one patients were included and divided into two cohorts: ER-EUS (n = 139) and EC-EUS (n = 82) cohorts. With propensity score matching method, 70 cases in each cohort were selected for the comparison. There was no significant difference in sensitivity, specificity, and area under the ROC curve to detect pancreatic malignancy between ER-EUS and EC-EUS cohort (88.5 vs. 100%, 88.6 vs. 90.9%, 0.8855 vs. 0.9545). CONCLUSION: ER-EUS and EC-EUS provided similar accuracy for the detection of pancreatic malignancies. In view of similar diagnostic results of ER-EUS and EC-EUS for the detection of pancreatic malignancy, and the advantage of being able to perform FNA with EC-EUS, EC-EUS may be the preferred choice.

EUS-guided rendezvous drainage for pancreatic duct obstruction from stenosis of pancreatojejunal anastomosis after pancreatoduodenostomy.

A 79-year-old man underwent pancreatoduodenectomy with Imanaga reconstruction for an ampullary adenocarcinoma in 2003. After that, he experienced recurrent pancreatitis with a suspicious stenotic pancreatojejunal anastomosis. Although endoscopic drainage through the pancreatojejunal anastomosis was attempted, the stenotic anastomosis could not be located endoscopically. Therefore, endosonography-guided rendezvous drainage through the anastomosis was performed, and endoscopic pancreatic stent placement was successfully completed. Thereafter, the patient did not experience any further attacks of pancreatitis. Endosonography-guided rendezvous drainage is a feasible treatment option for recurrent pancreatitis due to stenosis of pancreatojejunal anastomosis.

Novel quantitative perfusion analysis with contrast-enhanced harmonic EUS for differentiation of autoimmune pancreatitis from pancreatic carcinoma.

OBJECTIVE: Autoimmune pancreatitis (AIP) is often misdiagnosed as pancreatic carcinoma (PC) despite recent advances in imaging tests. The aim of the study was to evaluate whether the quantitative perfusion analysis using software "Time intensity curve" with contrast-enhanced harmonic EUS (CH-EUS) facilitate the differentiation of AIP from PC. METHODS: Consecutive patients with focal AIP and pancreatic carcinoma who underwent CH-EUS from January 2009 to September 2010 were analyzed. CH-EUS was performed with intravenous administration of an ultrasonographic contrast (Sonazoid) and electronic radial echoendoscope. The graph of time intensity curve (TIC) for pancreatic mass was generated to depict the changes in signal intensity over time within the region of interest (ROI). ROI was placed to cover an area with a pancreatic mass lesion. Based on the analysis of TIC, base intensity before injection (BI), peak intensity (PI), time to peak, and maximum intensity gain (MIG: PI-BI) were calculated. RESULTS: Eight patients with focal AIP and twenty-two patients with PC were evaluated by TIC. PI and MIG of mass lesion of AIP were significantly higher than that of PC (21.4 dB vs. 9.6 dB, 17.5 vs. 6.6). Receiver operating characteristics analysis yielded an optimal MIG cutoff value of 12.5 with high sensitivity and specificity. CONCLUSION: Pancreatic mass lesions of AIP and PC exhibited markedly different patterns with the TIC. This novel diagnostic modality using TIC generated by CH-EUS might offer an opportunity to improve accuracy in the differential diagnosis between pancreatic mass lesion of AIP and PC.

Clinical usefulness of diffusion-weighted MR imaging for detection of pancreatic cancer: comparison with enhanced multidetector-row CT.

PURPOSE: The aim of this study was to compare diffusion-weighted magnetic resonance imaging (DWI) and multidetector-row computed tomography (MDCT) for detection of primary pancreatic cancer by reviewing images of patients at high risk for pancreatic cancer with main pancreatic duct (MPD) dilatation shown by magnetic resonance cholangiopancreatography (MRCP). METHODS: From October 2007 to September 2009, 83 patients who had undergone both DWI and MDCT with MPD dilatation were identified and were reviewed by four readers (2 radiologists and 2 gastroenterology fellows). Diagnostic performance in pancreatic cancer detection was evaluated with 95% confidence intervals. Statistically significant differences in the detection of pancreatic cancer between DWI and MDCT were compared by receiver operating characteristics and the confidence of the diagnosis by the paired t test. RESULTS: Thirty-two of 83 patients were diagnosed with primary pancreatic cancer by histological evaluation of 15 surgical and 2 endoscopic ultrasound-guided fine needle aspiration samples, and by the clinical course for 15 lesions. Overall average accuracies of pancreatic cancer detection by the four readers were 84% with DWI and 86% with MDCT. CONCLUSION: Performance of DWI and MDCT was equivocal for detection of pancreatic cancer in a high-risk population with MPD dilatation. The combination of MRCP and DWI for detection of pancreatic cancer allowed identification of a high-risk population and tumor detection with a single imaging modality with no need for contrast medium.

Contrast-enhanced harmonic EUS with novel ultrasonographic contrast (Sonazoid) in the preoperative T-staging for pancreaticobiliary malignancies.

OBJECTIVE: Sonazoid is a new second-generation microbubble contrast for ultrasonography. In this pilot study, the diagnostic role of contrast-enhanced harmonic imaging endoscopic ultrasonography (CH-EUS) with Sonazoid was prospectively evaluated in preoperative T-staging of pancreaticobiliary malignancies. PATIENTS AND METHODS: Patients with suspected pancreaticobiliary malignancies underwent CH-EUS by a single examiner. After the lesions were observed carefully with conventional harmonic imaging EUS (H-EUS), CH-EUS was performed with intravenous injection of Sonazoid. A reviewer who was blinded reviewed the recordings of H-EUS and CH-EUS and assessed the T-staging. The accuracy of H-EUS and CH-EUS for T-staging was compared to the results of surgical histopathology in patients who underwent surgery. RESULT: Twenty-six patients underwent surgical resection and could be included in the study. The final diagnosis were pancreatic cancer in 11, bile duct cancer in 7, gallbladder cancer in 4 and ampullary cancer in 4. The overall accuracy of H-EUS and CH-EUS for T-staging were 69.2 (18/26) and 92.4% (24/26), respectively (p < 0.05). There were disagreement in six cases between H-EUS and CH-EUS. CH-EUS staged correctly in all of these six cases, whereas H-EUS misdiagnosed the depth of invasion in one case of gallbladder cancer and one case of ampullary cancer, and invasion of portal vein in two cases of pancreatic cancer and two cases of bile duct cancer. CONCLUSION: The depth of invasion of biliary cancer and vascular invasion of pancreatic and biliary cancer could be demonstrated more clearly with CH-EUS compared to H-EUS. CH-EUS has the potential to improve the diagnostic accuracy of preoperative T-staging of pancreaticobiliary malignancies.

Obstructive Jaundice Due to Hilar Bile Duct Compression with Encasement of the Right Hepatic Artery.

A 68-year-old woman had a solitary 12.0 cm hepatic cyst with a septum. The cyst was located near the hepatic hilum and she presented with obstructive jaundice caused by compression of the hilar bile duct. Stenosis of the common hepatic duct was detected at the porta hepatis on endoscopic retrograde cholangiography (ERC), and encasement of the right hepatic artery at the same level was revealed by abdominal angiography. Transpapillary cholangioscopy showed compression and mucosal erosions of the hilar bile duct. After transpapillary cholangioscopy, the hepatic cyst became infected, for which emergency percutaneous transhepatic drainage was performed. As a result, the patient's obstructive jaundice subsided. The mucosal erosions of the bile duct that existed at a site corresponding to the encasement of the right hepatic artery also improved. In conclusion, bile duct stenosis was considered to be caused by compression due to the hepatic cyst and the right hepatic artery.

Usefulness of pancreatic duct stenting prior to surgery as a guide to decide the feasibility of limited pancreatic resection.

BACKGROUND/AIMS: The purpose of this study was to introduce our procedure of limited pancreatic resection with preoperative pancreatic duct stenting to prevent complications. PATIENTS AND METHODS: Subjects comprised 6 patients with neoplasm who underwent preoperative pancreatic stenting. Pancreatic stents were placed within 7 days before elective surgery. After intraoperative ultrasonography, the relationship between the main pancreatic duct (MPD) and the lesion was confirmed by measuring the distance. Partial resection was surrendered if a sufficient margin of excised tumor was not obtained or injury to the MPD was likely to occur. Branches of pancreatic duct recognized were ligated as much as possible. RESULTS: Mild pancreatitis was present after stenting in 2 patients. Three patients actually underwent partial resection. In patients with partial resection, enhanced visualization of the MPD was useful for deciding the operative procedure and prevented iatrogenic injury to the MPD during dissection. CONCLUSIONS: Pancreatic duct stenting prior to pancreatic surgery seems useful as a guide for determining the feasibility of limited pancreatic resection and to prevent missing injury to the MPD.

Does preoperative pancreatic duct stenting prevent pancreatic fistula after surgery? A cohort study.

BACKGROUND/OBJECTIVE: Postoperative pancreatic fistula remains a major complication after pancreatic surgeries. To prevent pancreatic fistula, one of the employed management strategies is pancreatic duct stenting. The purpose of this study was to evaluate the efficacy and safety of preoperative pancreatic stenting to prevent pancreatic fistula after surgery. METHODS: Subjects comprised 18 consecutive patients who underwent pancreatic surgeries. Patients were divided into 2 groups: stenting group (n=7); and non-stenting group (n=11). Complications after stent placement were analyzed. Compared parameters between groups included background, incidence and grading of pancreatic fistula as judged by international study group of pancreatic fistula (ISGPF) criteria, duration until drain removal, and mean maximum level of drain amylase. RESULTS: Two patients displayed mild pancreatitis with high serum amylase levels after stenting. No significant differences in background or any other compared parameters to assess drainage effect were identified between stenting and non-stenting groups. Complications related to placement of the stent tube occurred in 4 patients with tube occlusion or cholestasis. CONCLUSIONS: Although drainage effect in the stenting group was compared with that in the non-stenting group, no obvious effect was obtained. This procedure seems to require further investigation on indications for postoperative drainage to decrease the incidence of pancreatic fistula.

Diagnostic approach using endosonography guided fine needle aspiration for lymphadenopathy in primary sclerosing cholangitis.

We report a case of primary sclerosing cholangitis (PSC) with benign lymphadenopathy which was diagnosed with endosonography guided fine needle aspiration (EUS-FNA). A 65-year-old woman was admitted to Jikei University Hospital with severe jaundice. Although endoscopic retrograde cholangiography and liver biopsy revealed the findings consistent with PSC, abdominal computed tomography revealed numerous large perihepatic lymph nodes with a maximum diameter of more than 3 cm. Therefore, EUS-FNA was done in order to exclude malignant lymphadenopathy, and adequate specimens obtained by EUS-FNA showed reactive hyperplasia of lymph node. The patients were scheduled to undergo liver transplantation.

Is metallic stenting worthwhile for biliary obstruction due to lymph node metastases?

BACKGROUND: The indications for metallic stents have widened from primary hepatobiliary cancers to the other diseases such as lymph node metastases from distant organs. The present study aimed to evaluate the results and establish the efficacy of metallic stenting in patients with obstructive jaundice due to metastatic lymph nodes. METHODS: Stent patency, survival and cost per patient until death were retrospectively compared between patients with primary carcinoma of the biliary tract (PC group; n = 71) and lymph node metastases from the gastric and colorectal carcinomas. (LN group; n = 26). RESULTS: Stent occlusion occurred in 17 patients in the PC group (24%). In contrast, stent occlusion was significantly more frequent in the LN group (P = 0.0293), occurring in 13 patients (50%). Cumulative stent patency was also significantly shorter in the LN group than that in the PC group (P = 0.0016). However, survival was almost the same between the two groups. The mean medical fee was 27% higher for the LN group than for the PC group, which was attributable to additional treatment for stent occlusion. DISCUSSION: The indications for metallic stent placement for biliary obstruction caused by lymph node metastases from the gastrointestinal tract seem limited. Further investigation of the treatments alternative to metallic stents would be required.

New approach to diagnosing ampullary tumors by magnifying endoscopy combined with a narrow-band imaging system.

BACKGROUND: A newly developed narrow-band imaging (NBI) system, which uses modified optical filters, can yield clear images of microvessels and surface structure in gastric and colonic diseases. In the present study, we investigated the ability of magnifying endoscopy with NBI (MENBI) to diagnose and differentiate between benign and malignant ampullary tumors. METHODS: Fourteen patients, whose ampullas were noted to be significantly enlarged or protruding with conventional endoscopy, were enrolled in the study. Specimens, which were obtained by forceps biopsy, endoscopic papillectomy, and/or surgery, were retrieved for histopathological examination. The correlation between MENBI images and histopathological findings was investigated. MENBI findings were classified as I, oval-shaped villi; II, pinecone/leaf-shaped villi; or III, irregular/nonstructured. In addition, tortuous, dilated, and network-like vessels noted on the ampullary lesions with MENBI were defined as abnormal vessels. RESULTS: In 6 of 14 patients, the ampullary changes were proven to be inflammatory in forceps biopsy specimens, without any evidence of malignancy after more than 1 year of follow-up. In five patients, ampullary lesions were treated by endoscopic papillectomy, and in three, by pancreatoduodenectomy. All adenomas and adenocarcinomas had type II and/or type III surface structures, and patients whose ampulla had a type I surface structure had only inflammatory or hyperplastic changes. In addition, abnormal vessels were seen only in adenocarcinomas and never in adenomas. CONCLUSIONS: MENBI has the ability and potential to predict histological characteristics of ampullary lesions.

Placement of a metallic stent across the main duodenal papilla may predispose to cholangitis.

BACKGROUND: Cholangitis is a major complication after metallic stent placement to treat biliary obstruction, and it may impair quality of life. Whether transpapillary stent placement contributes cholangitis is still controversial. OBJECTIVES: The present study aimed to determine risk factors for acute cholangitis after metallic biliary stent placement. DESIGN: Retrospective cases series. PATIENTS: A total of 108 patients with malignant biliary obstruction were treated with metallic stents, resulting in 12 cases of cholangitis. MAIN OUTCOME MEASUREMENTS: A multiple logistic regression model was performed with clinical parameters, including stent placement across the main duodenal papilla. RESULTS: By multiple logistic regression model, age; lower location; and Wallstent, Ultraflex stent, and covered stent were negatively associated with cholangitis. Restenosis and placement across the main duodenal papilla were positively associated with the occurrence of cholangitis. Transpapillary stent placement was the most significant risk factor. In this logistic model, the area under a receiver operating characteristics curve was computed as 0.92: sensitivity, 0.92 (95% confidential interval (CI), 0.62-1.00); specificity, 0.86 (95% CI, 0.78-0.93); positive predictive value, 0.46 (95% CI, 0.26-0.67); and negative predictive value, 0.99 (95% CI, 0.94-1.00). CONCLUSIONS: Disruption of the sphincter mechanism by transpapillary placement may be the most important etiologic factor in the propensity for cholangitis after metallic stent placement for malignant biliary obstruction.

A novel 3-dimensional EUS technique for real-time visualization of the volume data reconstruction process.

BACKGROUND: Three-dimensional EUS (3D-EUS) technology has facilitated spatial interpretation of US images. However, acquisition of consecutive US scans is time consuming and difficult. A new 3D-EUS system was developed that negates this problem by allowing rapid image renewal and the efficient production of consecutive US scans. METHODS: Three-dimensional images were reconstructed from a series of 2-dimensional images corresponding to the rotation angle of the echoendoscope as measured with an electromagnetic tracking system. To evaluate the technical feasibility of the system, 3-dimensional images of splenic veins in 2 patients and an esophageal submucosal tumor in a third patient were generated. RESULTS: The 3D-EUS system acquired image data at a rate of 30 frames per second and allowed visualization of these data in real-time. The area of interest was clearly and rapidly portrayed in all 3 patients. CONCLUSION: This study demonstrates the efficiency of the new 3D-EUS system described in this report. Further development of this novel 3D-EUS system may lead to new applications of this technology.