Performance of novel tissue harmonic echo imaging using endoscopic ultrasound for pancreatic diseases.

BACKGROUND AND STUDY AIMS: Recently, tissue harmonic echo (THE) imaging has advanced with the development of a new endoscopic ultrasound (EUS) monitor/processing unit. With this new technology, penetration (THE-P) and resolution (THE-R) images can be obtained. The aim of this study was to investigate the performance of this novel THE imaging using a new processing unit for pancreatic diseases. PATIENTS AND METHODS: Fifty patients with pancreatic lesions (38 cystic, 12 solid) were retrospectively analyzed. At each examination, 3 EUS images of the same pancreatic lesion were obtained using B-mode, THE-P mode, and THE-R mode imaging. Each set of EUS images was randomly arranged and evaluated independently by 4 physicians blinded to the imaging technique. Images were compared using a Likert scale 5-point grading system for each parameter. RESULTS: For cystic lesions, THE-P mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, nodules, and total image quality (P < 0.05). THE-R mode images were significantly superior to conventional B-mode images for visualizing the boundary, septum, and total image quality (P < 0.05). However, for solid lesions, there was no significant difference in all the evaluation points between THE-P and conventional B-mode images. THE-R mode images were inferior to conventional B-mode images for visualizing the boundary, internal structure, and total image quality (P < 0.05). CONCLUSIONS: For pancreatic cystic lesions, THE mode images provided better lesion characterization than conventional B-mode images. Further research is required to determine if this improvement will result in improved EUS diagnostics.

Diagnostic ability of EUS-FNA for pancreatic solid lesions with conventional 22-gauge needle using the slow pull technique: a prospective study.

OBJECTIVE: Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) using the slow pull technique (SP-FNA) has recently attracted attention as an effective tissue acquisition technique. However, efficacy of SP-FNA with a 22-gauge conventional needle remains unclear. The aim of this study is to evaluate the diagnostic ability of SP-FNA with a 22-gauge needle. MATERIAL AND METHODS: Patients with a pancreatic solid lesion were prospectively enrolled in this study. SP-FNA was performed at two needle passes with a 22-gauge needle. One dedicated pathologist evaluated the obtained samples in terms of quantity (Grade 0: scant; Grade 1: inadequate; Grade 2: adequate), quality (Grade 0: poor; Grade 1: moderate; Grade 2: good), and blood contamination (Grade 0: significant; Grade 1: moderate; Grade 2: low), and provided a pathological diagnosis. Additional EUS-FNA was performed by applying suction (SA-FNA). The evaluation points were as follows: diagnostic accuracy of SP-FNA compared with that of SA-FNA, and the quantity, quality, and blood contamination level of SP-FNA-obtained samples. RESULTS: We enrolled 40 cases. The diagnostic accuracy of SP-FNA was 90% (36/40). There was no significant difference in the accuracy between SP-FNA and SA-FNA (90% vs. 90%, p = 1.000). The samples obtained using SP-FNA were assessed as Grade 2 for quantity in 29 cases (73%), quality in 31 (78%), and blood contamination in 25 (63%). CONCLUSIONS: Adequate, high-quality, and unsubstantially blood-contaminated samples could be obtained using SP-FNA. The diagnostic ability of SP-FNA was 90%, which appeared to be similar to that of SA-FNA.

Bench-top testing of suction forces generated through endoscopic ultrasound-guided aspiration needles.

BACKGROUND: Adequate needle size and tissue acquisition techniques for endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) need further elucidation. Moreover, the actual negative pressure and suction forces of FNA needles remain unknown. We evaluated the suction forces of 19-gauge, 22-gauge, and 25-gauge conventional FNA needles and side hole aspiration needles using conventional negative pressure and the slow pull technique. METHODS: Using a manometer, we determined the mean (SD) negative pressure and suction force for needle gauge, aspiration volume, and aspiration technique. We also evaluated the time to reach the maximum negative pressure. RESULTS: Suction force was comparatively higher in the 19-gauge needle when 50 ml of negative pressure was applied. Suction force using the slow pull method was very weak at 5% of pressure found with conventional methods. With the use of a 20-ml syringe, the time to reach the maximum negative pressure was 4 s in the 19-gauge needle, 11 s in the 22-gauge needle, and 80 s in the 25-gauge needle. CONCLUSIONS: Bench-top testing showed that suction force increases with a larger gauge needle and larger aspiration volume. The slow pull method produces a very weak suction force. The time to reach the maximum negative pressure was longest in the 25-gauge needle.

No benefit of endoscopic sphincterotomy before biliary placement of self-expandable metal stents for unresectable pancreatic cancer.

BACKGROUND & AIMS: Endoscopic sphincterotomy (ES) is performed routinely before self-expandable metallic stents (SEMS) are placed in malignant distal biliary strictures to prevent postprocedural pancreatitis. However, it is not clear whether ES actually prevents pancreatitis or affects other adverse events (AEs). We conducted a noninferiority trial to examine the necessity of ES before SEMS placement. METHODS: Two hundred patients with distal biliary strictures caused by unresectable pancreatic cancer were assigned randomly to groups that received ES or did not receive ES (non-ES) before SEMS placement, at 25 hospitals in Hokkaido, Japan, from August 2010 through November 2012. The primary outcome was early AEs (≤30 d) specifically related to the presence or absence of ES (pancreatitis, bleeding, or perforation). Secondary outcomes measured included the effect of ES omission on time to SEMS dysfunction and patient survival times. RESULTS: The proportions of patients with early AEs were 9.2% in the non-ES group and 10.4% in the ES group (a difference of 1.2%, noninferior). The median times to SEMS dysfunction was longer than 594 days in the non-ES group and 541 days in the ES group (P = .88). The median overall survival times were 202 in the ES group vs 255 days in the non-ES group; P = .20). CONCLUSIONS: ES before SEMS does not affect the incidence of AEs, SEMS patency, or patient survival times. Our data provide no evidence for a benefit of ES to patients undergoing SEMS placement for a biliary stricture caused by pancreatic cancer. UMIN clinical trials registry number: 000004044.

Feasibility, efficacy, and predictive factors for the technical success of endoscopic nasogallbladder drainage: a prospective study.

BACKGROUND/AIMS: Several studies have shown the useful-ness of endoscopic nasogallbladder drainage (ENGBD) in patients with acute cholecystitis. However, the procedure is difficult, and factors that affect technical success have not yet been clarified. We conducted a prospective study to eval-uate the technical feasibility, efficacy, and predictive factors for the technical success of ENGBD in patients with acute cholecystitis. METHODS: All patients with moderate or severe acute cholecystitis who were enrolled underwent ENGBD between April 2009 and April 2011. Patients with surgically altered anatomy or pancreatobiliary malignancies were ex-cluded. The primary outcomes included technical success, clinical success, and complications. Factors that could affect the technical success were also examined. RESULTS: Of the 27 patients who underwent ENGBD during the study period, technical success was achieved in 21 (78%) and clinical improvement was achieved in 20 (95%). Early complications were encountered in four patients (15%). Gallbladder wall thickness (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.08 to 2.47) and age (OR, 1.16; 95% CI, 1.00 to 1.35) were effective predictors of technical failure. CONCLUSIONS: ENGBD was effective in resolving acute cholecystitis; however, this modality was technically challenging and had a limited suc-cess rate. Because of technical difficulties, ENGBD should be reserved for limited indications. (Gut Liver, 2015;9239-246).

Validation of a nomogram for predicting the probability of carcinoma in patients with intraductal papillary mucinous neoplasm in 180 pancreatic resection patients at 3 high-volume centers.

OBJECTIVE: We previously published a nomogram for prediction of carcinoma in patients with intraductal papillary mucinous neoplasm (IPMN). The objective of the current study was to validate this nomogram in an external cohort of patients at multiple institutions. METHODS: The clinical details of 180 patients with IPMN who underwent a pancreatic resection at 3 hospitals were collected. Four significant predictive factors (sex, lesion type, nodule height, and pancreatic juice cytology) were analyzed. RESULTS: Of the 180 patients, 66 (36.7%) had a main pancreatic duct-type IPMN and 114 (63.3%) had a branch pancreatic duct-type IPMN. The final pathological diagnosis was benign IPMN in 95 (52.8%) patients and malignant IPMN in 85 (47.2%) patients. The area under the receiver operating characteristic curve for the model was 0.760. The area under the receiver operating characteristic curve of the IPMN nomogram for prediction of malignancy was 0.747 in main pancreatic duct-type IPMN and 0.752 in branch pancreatic duct-type IPMN. The sensitivity and specificity of the model were 80.0% and 57.9%, respectively, when the predictive probability of more than 10% was used to indicate the presence of carcinoma. CONCLUSIONS: This nomogram for predicting the probability of carcinoma in patients with IPMN was accurate in an external validation patient cohort.

Prospective, randomized, comparative study of delineation capability of radial scanning and curved linear array endoscopic ultrasound for the pancreaticobiliary region.

BACKGROUND AND STUDY AIMS: There are two types of endoscopic ultrasound (EUS) endoscope, the radial scanning (RS) and the curved linear array (CL). The type of EUS endoscope used at a first intent depends on local expertise, local habits and sometimes on how the examination is reimbursed. In Japan, RS is mainly used for observation, whereas CL is primarily used for histopathological diagnosis and treatment. We compared the imaging capabilities of RS and CL in evaluating the pancreaticobiliary region, a study which has not been performed previously. PATIENTS AND METHODS: This prospective and randomized trial included 200 patients undergoing endoscopic ultrasonography of the pancreaticobiliary region by RS (n = 99) or CL (n = 101). The primary end point was the basal imaging capability of each technique. Eleven pancreaticobiliary areas were assessed and scored (range, 0 - 2). Endoscopists evaluated each criterion, and a transcriber recorded the decisions in real time. RESULTS: The mean imaging scores in the RS and CL groups were 18.39 and 19.62, respectively (significantly higher in CL, 95 %CI: 0.82 - 1.64). Although no significant difference in imaging capability for the pancreatic head, body, or tail was observed between CL and RS, the imaging capability of CL for the pancreatic head - body transition region was superior to that of RS. Although no significant difference in imaging capability for the middle and inferior bile duct or the cystic duct was observed between CL and RS, the imaging capability of RS for the major duodenal papilla and gallbladder was superior to that of CL. For the area from the hepatic portal region to the superior bile duct, the imaging capability of CL was superior. In the delineation of the branch area of the celiac and superior mesenteric arteries, CL was also superior to RS. CONCLUSIONS: The non-inferiority of the overall imaging capability of CL to that of RS was demonstrated. CL was superior in the delineation of the pancreatic head - body transition region, the area from the hepatic portal region to the superior bile duct, and the vascular bifurcation, whereas RS was superior in the delineation of the major duodenal papilla and gallbladder. Thus, for detailed evaluations of specific areas, the choice of scope should probably be considered.

Endoscopic retrograde cholangiopancreatography in patients with surgically altered anatomy using balloon-assisted enteroscope.

Endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy involves challenging procedures for ERCP endoscopists. In these patients, the anatomical structure of the intestine is substantially altered, and an endoscope needs to be inserted into the long afferent limb. Moreover, the papilla is observed in the opposite view from the normal anatomy. Recently, a balloon-assisted enteroscope (BAE) has been developed and made available for use in daily practice. The two types of BAE are single-balloon enteroscope (SBE), which is inserted with one balloon attached to the overtube using a balloon-assisted method, and double-balloon enteroscope (DBE), which is inserted with two balloons, one attached to the overtube and the other attached to the tip of the enteroscope. In addition, short-type DBE (short-DBE) and short-type SBE (short-SBE) with a working length of approximately 150 cm, which could be used with various ERCP accessories, are commercially available or under development. Notably, the success rate of ERCP through coordinated manipulation with a balloon was remarkably improved with the use of BAE, even in patients with surgically altered anatomy. Here, we report the current status and procedures of ERCP in patients with surgically altered anatomy.

Efficacy, Safety, and Long-Term Follow-Up Results of EUS-Guided Transmural Drainage for Pancreatic Pseudocyst.

Background and Aim. EUS-guided transmural drainage (EUS-GTD) is now considered a minimally invasive and effective alternative to surgery for drainage of symptomatic pancreatic pseudocysts. However, the technique is rather difficult, and sometimes serious complications occur to patients undergoing this procedure. We retrospectively evaluated efficacy, safety, and long-term follow-up results of EUS-GTD for pancreatic pseudocyst. Methods. Sixty-seven patients with pancreatic pseudocyst who underwent EUS-GTD from April 2000 to March 2011 were enrolled. We retrospectively evaluated (1) technical success, (2) clinical success, (3) adverse event of procedure, and (4) long-term follow-up results. Results. Total technical success rate was 88%. Ninety-one percent of external drainage, 79% of internal drainage, and 66% of puncture and aspiration only achieved clinical success. There was only one case with an adverse event, perforation (1.5%). The case required emergency operation. Total recurrence rate was 23.9%. Median follow-up period was 33.9 months. The recurrence rates in the cases of stent remaining, spontaneously dislodged, removed on schedule, external tube removal, and aspiration only were 10.0%, 12.5%, 42.9%, 50%, and 0%, respectively. Conclusion. EUS-GTD is a relatively safe and effective therapeutic method. However, further analysis should be done by larger series to determine the method of EUS-GTD for pancreatic pseudocyst.

Predictors of malignancy in intraductal papillary mucinous neoplasm of the pancreas: analysis of 310 pancreatic resection patients at multiple high-volume centers.

OBJECTIVES: The present study was a retrospective investigation of predictors of malignancy in intraductal papillary mucinous neoplasm (IPMN) of the pancreas. METHODS: The subjects were 310 patients who underwent pancreatic resection at 3 high-volume centers. Preoperative laboratory and imaging findings were analyzed in logistic regression analyses. Endoscopic ultrasonography measurements were essential for the size of mural nodules, and a central review was conducted for pathological diagnosis. RESULTS: Pathological diagnosis was benign IPMN in 150 cases and malignant in 160 (noninvasive carcinoma, n = 100; invasive, n = 60). In multivariate analysis, size of mural nodules, diameter of main pancreatic duct, and cyst size of branch pancreatic duct were independent predictors of malignancy, and areas under the receiver operating characteristic curve for these 3 factors were 0.798, 0.643, and 0.601, respectively. With 7 mm taken as the cutoff value for the size of mural nodules, the diagnosis of malignant IPMN had sensitivity of 74.3% and specificity of 72.7%. Carcinoma without nodules was present in 15 patients (15/160 [9.4%]). CONCLUSIONS: The size of mural nodules measured with endoscopic ultrasonography showed high predictive ability. However, about 10% of carcinoma patients did not have nodules, and the handling of the diagnosis in such cases is a problem for the future.

Factors predictive of adverse events associated with endoscopic ultrasound-guided fine needle aspiration of pancreatic solid lesions.

BACKGROUND: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) provides high diagnostic accuracy with a low incidence of procedural complications. However, it occasionally causes serious complications, and factors that increase the susceptibility to such adverse events remain unknown. AIMS: We aimed to examine post-procedural events and determine risk factors associated with EUS-FNA of pancreatic solid lesions. METHODS: This single-center retrospective study included 316 consecutive patients with pancreatic solid lesions who underwent 327 EUS-FNA procedures from April 2003 to September 2011. We registered all patients undergoing EUS-FNA in the database and retrospectively ascertained the presence/absence of post-procedural adverse events. RESULTS: The incidence of post-procedural adverse events, including moderate to mild pancreatitis, mild abdominal pain, and mild bleeding, was 3.4 %. Univariate analysis showed that the incidence of post-procedural events was significantly increased in patients with tumors less than or equal to 20 mm in diameter (P < 0.001), those with pancreatic neuroendocrine tumors (PNET) (P = 0.012), and patients who had intervening normal pancreas for accessing the lesion (P = 0.048). Multivariate analysis identified tumors measuring less than or equal to 20 mm in diameter (OR 18.48; 95 % CI 3.55-96.17) and case of PNETs (OR 36.50; 95 % CI 1.73-771.83) were an independent risk factors. CONCLUSIONS: EUS-FNA of pancreatic solid lesions is a safe procedure. However, pancreatic lesions with small diameters and pancreatic neuroendocrine tumors are important factors associated with adverse events after EUS-FNA.

[A case of adenoendocrine cell carcinoma on the ampulla of Vater].

The occurrence of an adenoendocrine cell carcinoma on the ampulla of Vater is rare, especially when the component of adenocarcinoma is not located on the mucosa of the ampulla. A 76-year-old man was referred to our hospital for further investigation of a mass lesion on the ampulla. EGD revealed SMT like mass lesion on the ampulla. Endoscopic ultrasonography showed an ampullary hypoechoic mass. We performed pylorus-preserving pancreatoduodenectomy on the basis of the diagnosis of poorly differentiated adenocarcinoma of the ampulla of Vater. Postoperative pathological examinations revealed two different components of the tumor;malignant endocrine cells, and adenocarcinoma. The component of adenocarcinoma was located on the Ap lesion. We deducted that the adenocarcinoma appeared on the epithelium of Ap, then grew and spread into the direction of duodenum lumen, degenerating to endocrine cells.