Katsushige Gon

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

Abstract 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.

Comparison of modified introducer method with pull method for percutaneous endoscopic gastrostomy: prospective randomized study.

Aim:  The pull method is associated with a high incidence of percutaneous endoscopic gastrostomy (PEG) site infection. The introducer method has been shown to be less likely to cause infection, because it avoids the passage of a tube through the oropharynx. The aim of the present study was to compare the modified introducer method with the pull method for PEG.

Is endoscopic papillary large balloon dilatation without endoscopic sphincterotomy effective

AIM To evaluate the safety and efficacy of endoscopic papillary large balloon dilatation (EPLBD) without endoscopic sphincterotomy in a prospective study. METHODS From July 2011 to August 2013, we performed EPLBD on 41 patients with naïve papillae prospectively. For sphincteroplasty of EPLBD, endoscopic sphincterotomy (EST) was not performed, and balloon diameter selection was based on the distal common bile duct diameter. The balloon was inflated to the desired pressure. If the balloon waist did not disappear, and the desired pressure was satisfied, we judged the dilatation as complete. We used a retrieval balloon catheter or mechanical lithotripter (ML) to remove stones and assessed the rates of complete stone removal, number of sessions, use of ML and adverse events. Furthermore, we compared the presence or absence of balloon waist disappearance with clinical characteristics and endoscopic outcome. RESULTS The mean diameters of the distal and maximum common bile duct were 13.5 ± 2.4 mm and 16.4 ± 3.1 mm, respectively. The mean maximum transverse-diameter of the stones was 13.4 ± 3.4 mm, and the mean number of stones was 3.0 ± 2.4. Complete stone removal was achieved in 97.5% (40/41) of cases, and ML was used in 12.2% (5/41) of cases. The mean number of sessions required was 1.2 ± 0.62. Pancreatitis developed in two patients and perforation in one. The rate of balloon waist disappearance was 73.1% (30/41). No significant differences were noted in procedure time, rate of complete stone removal (100% vs 100%), number of sessions (1.1 vs 1.3, P = 0.22), application of ML (13% vs 9%, P = 0.71), or occurrence of pancreatitis (3.3% vs 9.1%, P = 0.45) between cases with and without balloon waist disappearance. CONCLUSION EST before sphincteroplasty may be unnecessary in EPLBD. Further investigations are needed to verify the relationship between the presence or absence of balloon waist disappearance.

Newly designed J-shaped tip guidewire: a preliminary feasibility study in wire-guided cannulation.

AIM To perform wire-guided cannulation using a newly designed J-shaped tip guidewire, and to verify feasibility and safety for use. METHODS The study was conducted on endoscopic retrograde cholangiopancreatography (ERCP) patients with naïve papilla undergoing diagnosis and treatment of biliary diseases between September 2011 and July 2012. We performed ERCP in a succession of 50 cases with a J-shaped tip guidewire. The first insertion attempt began with a trainee who had 5 min to complete cannulation, followed if necessary by the trainer for another 5 min. We assessed the primary success rate of selective biliary cannulation within 10 min and adverse events such as post-ERCP pancreatitis (PEP), bleeding or perforation. RESULTS The primary success rate was 90% (45/50) within 10 min, the initial success rate within 5 min by trainee staff was 76% (38/50). The rate of PEP was 6% (3/50), but all 3 cases were mild pancreatitis. All patients were managed successfully with conservative treatment. There was no bleeding or perforation. CONCLUSION A newly designed J-shaped tip guide-wire has the possibility to facilitate selective biliary cannulation for ERCP and appears to be safe.

Feasibility, Efficacy, and Predictive Factors for the Technical Success of Endoscopic Nasogallbladder Drainage: A Prospective Study

Background/Aims Several studies have shown the usefulness 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 evaluate 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 excluded. 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 success rate. Because of technical difficulties, ENGBD should be reserved for limited indications.

A novel dry model for practicable sphincterotomy and precut needle knife sphincterotomy.

Aim. We aimed to develop a simulation dry model for endoscopic sphincterotomy (ES) and needle knife precut sphincterotomy (NKP) and to evaluate its usefulness as a training simulator. Materials and Methods. An endoscopic retrograde cholangiopancreatography trainer was used as a duodenum, bile duct, and papilla simulator. A simulated papilla was created with a piece of rolled uncured ham, and ES and NKP were performed. Hands-on training was carried out using this model, and success and failure of the procedures were evaluated. A questionnaire survey was conducted among the participants to assess the performance and usefulness of the dry model for ES and NKP training. Results. Twenty-two endoscopists participated in the hands-on training using this dry model. ES was successful in 33 out of 34 attempts (97%) whereas NKP was successful in all 7 attempts (100%). Based on the results of the questionnaire survey, the median score for realism was 7 (range: 2–9) for ES and 8 for NKP on a scale of 1 to 10. Conclusions. The dry model using an uncured ham provides a condition closely similar to actual clinical practice and is useful as a training model for ES and NKP.

Direct Peroral Cholangioscopy Using an Ultraslim Upper Endoscope for Biliary Lesions

BACKGROUND The development of direct peroral cholangioscopy (DPOC) using an ultraslim endoscope simplifies biliary cannulation. The conventional techniques are cumbersome to perform and require advanced skills. The recent introduction of the guidewires and balloons has improved the therapeutic outcomes. Here we describe an effective and easier method for performing DPOC using an ultraslim upper endoscope. METHODS Indications for DPOC were the presence of stones on follow-up of patients who had previously undergone complete sphincteroplasty, including endoscopic sphincterotomy or endoscopic papillary large balloon dilatation. Fifteen patients underwent DPOC. An ultraslim endoscope was inserted perorally and was advanced into the major papilla. The ampulla of Vater was visualized by retroflexing the endoscope in the distal second portion of the duodenum, and then DPOC was performed using a wire-guided cannulation technique with an anchored intraductal balloon catheter. RESULTS One patient failed in the treatment due to looping of the endoscope in the fornix of the stomach. Fourteen (93.3%) were successfully treated with our modified DPOC technique. Only one patient (6.7%) experienced an adverse event (pancreatitis) who responded well to conservative management. Residual stones of the common bile duct were completely removed in 3 patients. CONCLUSION The modified method of DPOC is simple, safe and easy to access the bile duct.

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.

Endoscopic management of benign biliary stricture: should we treat more aggressively?

BENIGN BILIARY STRICTURES (BBS) have various etiologies, including intraoperative injury, postoperative stenosis, chronic pancreatitis, and primary and secondary cholangitis. Stasis of the bile juice causes abdominal pain, fever, and jaundice. At present, endoscopic biliary stenting or balloon dilatation is considered to be the first-line treatment for BBS. Recent advances in endoscopic techniques and various accessories have allowed successful treatment of most BBS cases. However, a consensus regarding the adequate management of BBS has not yet been reached. Moreover, various etiologies of BBS may confuse the choice of adequate treatment. Weber et al. reported interesting long-term follow-up results after endoscopic stent therapy for BBS depending on the various causes of the stricture. Intraoperative injury-induced stricture and postoperative stricture showed good follow-up results, whereas chronic pancreatitis-induced stricture revealed poor follow-up results. In terms of pathological findings, chronic pancreatitis was accompanied by not only fibrosis but also by swelling of the pancreas and calcification of the pancreatic parenchyma. These pathological conditions induce the formation of a difficult-to-resolve stricture. Single plastic stent placement is mainly used for the management of BBS. However, the single plastic stent does not usually achieve effective bile duct stricture resolution, and good long-term follow-up results. In addition, single plastic stents have short-term patency rates only, limited stent diameter, and a requirement for multiple endoscopic sessions. Moreover, most of the previous studies on single plastic stents are retrospective and have different patient selection criteria, dilatation methods, stent diameters, follow-up periods, and definitions of success. For these reasons, more aggressive treatments such as multiple plastic stent and covered metal stent insertions have been carried out. The concept of these treatments is to achieve larger dilatation of the stricture site. Costamagna et al. used multiple plastic stent insertion to obtain stricture resolution. They reported no recurrence of symptoms caused by a relapsing biliary stricture in 89 patients during a mean follow-up period of 48.8 months (range: 2–11.3 years). Catalano et al. treated symptomatic distal common bile duct stenosis and reported their prospective series compared with historical controls, together with a comparison of single versus multiple simultaneous plastic stents. Twelve consecutive patients with chronic pancreatitis and common bile duct stricture underwent endoscopic placement of multiple simultaneous plastic stents and were followed prospectively. Results were compared with a group of 34 patients in whom a single stent was placed. In the 12 patients with multiple stent placements, the diameter of the distal common bile duct stenosis increased from a mean of 1.0 mm to 3.0 mm post-treatment; no change in diameter was noted in the patients treated with a single stent. Theoretically, multiple stents have a larger boogie effect for stricture resolution than a single plastic stent. However, multiple plastic stent placement requires a longer procedure time and, in cases of tight strictures, it is difficult to pass and place multiple stents across the stricture. Another option for treating BBS is the placement of a metallic stent, which was first done in 1990. Unfortunately, an uncovered metallic stent was used which produced unsatisfactory results as the stent was difficult to remove because of endoluminal hyperplasia. To address this problem, covered self-expandable metallic stents (CSEMS) were used for BBS. CSEMS, particularly fully covered metallic stents (FCSEMS) can be reliably removed. Kahaleh et al. used CSEMS in 79 patients with BBS and confirmed stricture resolution in 90% of the patients. Although the dilating and stenting method has achieved successful resolution in most cases, 10–40% of BBS do not respond well. Moreover, stricture relapse may occur in 10–30% of cases after the initial resolution. Currently, the management of refractory BBS remains uncertain. In this issue of Digestive Endoscopy, Bing et al. report the most aggressive therapy for BBS using intraductal bipolar radiofrequency ablation (RFA). The treatment concept is aimed at using ablation power and treating the stricture rather than using the boogie effect. Endoscopic retrograde cholangiopancreatography and RFA therapy were carried out in nine patients. Among these patients, the causes of BBS included post-cholecystectomy injury in four patients, anastomotic stricture after liver transplantation in three, chronic inflammation in one and chronic pancreatitis in one. After RFA and balloon dilatation, stenosis of all the patients significantly improved and five patients (55%) met stricture resolution. Of the nine patients, three required no

What is the preferred shape for an esophageal stent flange

Aim:  Self‐expandable metallic stents (SEMS) for the gastrointestinal tract have different types of flanges at either the oral end or both ends to prevent stent migration. The effect of flange shape on the properties of SEMS, to our knowledge, has not been evaluated. The aim of this study was to measure the strain that a SEMS imposes on the adjacent wall and the anti‐migration force (AF) exerted by three stents, each with a different flange shape.