Mitsuyoshi Honjo

Endoscopic ultrasound-guided placement of plastic vs. biflanged metal stents for therapy of walled-off necrosis: a retrospective single-center series

BACKGROUND AND STUDY AIMS Recently, a novel fully covered and biflanged metal stent (BFMS)dedicated to the drainage of walled-off necrosis(WON) was developed. The aim of this study was to retrospectively evaluate the safety, efficacy, and cost performance of drainage of WON using the novel BFMS compared with a traditional plastic stent. PATIENTS AND METHODS A total of 70 patients with symptomatic WON were treated under endoscopic ultrasound (EUS) guidance. Initial drainage was conducted using the single gateway technique with placement of one or more plastic stents or a single BFMS.If drainage was unsuccessful,direct endoscopic necrosectomy (DEN)was performed. RESULTS There were no statistically significant differences in rates of technical success, clinical success,and adverse events between plastics stents and BFMS, despite the size of WON in the BFMS group being significantly larger than that in the plastic stent group (105.6 vs. 77.1 mm; P=0.003).The mean procedure times for the first EUS-guided drainage and for re-intervention were significantly shorter in the BFMS group than in the plastic stent group (28.8±7.1 vs. 42.6±14.2, respectively,for drainage, P<0.001; and 34.9±8.5 vs.41.8±7.6, respectively, for re-intervention, P<0.001). There was no statistically significant difference in the total cost between plastic stent and BFMS use in the treatment of WON (

A newly designed plastic stent for EUS-guided hepaticogastrostomy: a prospective preliminary feasibility study (with videos).

5352vs.

Initial evaluation of a new plastic pancreatic duct stent for endoscopic ultrasonography-guided placement.

6274; P=0.25). CONCLUSIONS Plastic stents and BFMS were safe and effective for the treatment of WON. In particular,BFMS placement appeared to be preferable for initial EUS-guided drainage and additional reintervention(e.g. DEN) as it reduced the procedure time. Prospective randomized controlled trials are warranted.

Safety trial of high-intensity focused ultrasound therapy for pancreatic cancer

BACKGROUND There are currently no dedicated plastic stents for EUS-guided hepaticogastrostomy (EUS-HGS). OBJECTIVE We prospectively evaluated the feasibility and the technical and functional success rates of our newly designed plastic stent for EUS-HGS. DESIGN Prospective preliminary feasibility study. SETTING A tertiary-care referral center. PATIENTS Twenty-three consecutive patients were treated. The reasons for requiring EUS-HGS were periampullary tumor invasion (n=9), altered anatomy (n=7), failed duodenal intubation (n=3), and previous ERCP failure (n=4). INTERVENTIONS An 8F single-pigtail plastic stent with 4 flanges was placed for EUS-HGS. MAIN OUTCOME MEASUREMENTS Technical success, clinical success, and adverse events according to the American Society for Gastrointestinal Endoscopy lexicon. RESULTS All stents were successfully deployed without procedural adverse events (100% technical success rate). Bleeding from the punctured gastric wall occurred in 1 patient 3 days postoperatively. We exchanged the plastic stent for a fully covered self-expandable metal stent. A mild adverse event of self-limited abdominal pain occurred in 3 patients. Treatment success was achieved in all patients. The occlusion rate was 13.7% (3/22) during the median follow-up period (5.0 months, range 0.5-12.5 months). The median duration of stent patency was 4.0 months (range 0.5-9.0 months). There was no stent migration or dislocation during the follow-up period. LIMITATIONS Small number of patients and lack of a control group. CONCLUSIONS This newly designed single-pigtail plastic stent dedicated for EUS-HGS was technically feasible and can possibly be used for highly selected patients with advanced malignancy or benign stricture. ( TRIAL REGISTRATION http://www.umin.ac.jp/english/: UMIN000012993.).

Is the double‐guidewire technique superior to the pancreatic duct guidewire technique in cases of pancreatic duct opacification?

There are currently no plastic pancreatic duct stents that have been designed for endoscopic ultrasonography (EUS)-guided placement. This study prospectively evaluated the feasibility and efficacy of a new, single-pigtail, plastic stent. Eight patients with main pancreatic duct stricture or stenotic pancreatojejunostomy underwent EUS-guided placement of the pancreatic duct stent. The stent was placed successfully in all cases (8/8). Treatment success was achieved in all cases (8/8). A mild adverse event associated with the procedure was observed in one patient but there were no other adverse events during a mean follow-up of 7.4 months. This new pancreatic duct stent appears to be feasible and effective for EUS-guided stenting.

Relationship Between the Liver Tissue Shear Modulus and Histopathologic Findings Analyzed by Intraoperative Shear Wave Elastography and Digital Microscopically Assisted Morphometry in Patients With Hepatocellular Carcinoma

AIM To evaluate the safety and clinical application of high-intensity focused ultrasound (HIFU) therapy for unresectable pancreatic cancer (PC). METHODS Thirty PC patients (16 cases in stage III and 14 cases in stage IV) with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy. Informed consent was obtained. This study began at the end of 2008 and was approved by the ethics committee of our hospital [Institutional Review Board (IRB): 890]. The HIFU device used was the FEP-BY02 (Yuande Bio-Medical Engineering, Beijing, China). RESULTS The mean tumor size after HIFU therapy changed to 30.9 ± 1.7 mm from 31.7 ± 1.7 mm at pre-therapy. There were no significant changes in tumor size, mean number of treatment sessions (2.7 ± 0.1 mm), or mean total treatment time (2.4 ± 0.1 h). The rate of symptom relief effect was 66.7%. The effectiveness of primary lesion treatment was as follows: complete response, 0; partial response, 4; stable disease, 22; progressive disease, 4. Treatment after HIFU therapy included 2 operations, 24 chemotherapy treatments, and 4 best supportive care treatments. Adverse events occurred in 10% of cases, namely pseudocyst formation in 2 cases and mild pancreatitis development in 1. However, no severe adverse events occurred in this study. CONCLUSION We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.

Creation of simulated papillae for endoscopic sphincterotomy and papillectomy training by using in vivo and ex vivo pig model (with videos)

Pancreatic duct guidewire placement (P‐GW) techniques include both the injection cannulation technique with a contrast medium and wire‐guided cannulation without contrast injection for selective biliary cannulation; the latter is the so‐called “double‐guidewire technique” (D‐GW). The aim of this study was to compare the outcomes between P‐GW and D‐GW for biliary cannulation.

Radiologic-pathologic correlation of three-dimensional shear-wave elastographic findings in assessing the liver ablation volume after radiofrequency ablation

Shear wave elastography is a novel noninvasive method for assessing liver fibrosis by measuring liver stiffness. This study was conducted to evaluate how pathologic changes could have an impact on measured elasticity values in both resected hepatocellular carcinomas and adjacent liver tissue.

Real-time virtual sonography visualization and its clinical application in biliopancreatic disease

BACKGROUND There are few in vivo and ex vivo models for training in endoscopic sphincterotomy (ES) and endoscopic papillectomy (EP). OBJECTIVE We describe in vivo and ex vivo training pig models that use a simulated papilla for hands-on teaching of ES and EP. DESIGN Animal experiment. SETTING A referral center. MATERIALS AND INTERVENTIONS Hyaluronate solution (0.4%) was injected submucosally using a 25-gauge sclerotherapy needle to create a submucosal bleb by using porcine in vivo stomach, ex vivo stomach, and ex vivo rectum. ES and EP were then performed by using a pull-type sphincterotome and snare, respectively. MAIN OUTCOME MEASUREMENT The feasibility of creating a simulated papilla for ES and EP procedures was tested by experienced and nonexperienced ERCP endoscopists. RESULTS Creation of a hemispheroidal bulge was successful in 13 of 17 (76%) areas within an in vivo stomach, 13 of 16 (81%) areas of an ex vivo stomach, and 16 of 16 (100%) areas in an ex vivo rectum. In the in vivo stomach model, ES was successfully and realistically performed on the anterior wall of the stomach rather than in other walls. In the ex vivo stomach model, endoscopists experienced in ERCP and trainees performed ES without difficulty, whereas it was difficult or impossible for nonexperienced trainees to perform ES. In the ex vivo rectum model, all 3 endoscopists were able to complete not only ES but also EP. LIMITATIONS Pilot study. CONCLUSIONS Although further studies are necessary to evaluate the reproducibility and cost-effectiveness, this novel pig model appears useful for ES and EP training.

Serum metabolomic profiles for human pancreatic cancer discrimination

AIM To evaluate the usefulness of three-dimensional (3D) shear-wave elastography (SWE) in assessing the liver ablation volume after radiofrequency (RF) ablation. METHODS RF ablation was performed in vivo in 10 rat livers using a 15-gauge expandable RF needle. 3D SWE as well as B-mode ultrasound (US) were performed 15 min after ablation. The acquired 3D volume data were rendered as multislice images (interslice distance: 1.10 mm), and the estimated ablation volumes were calculated. The 3D SWE findings were compared against digitized photographs of gross pathological and histopathological specimens of the livers obtained in the same sectional planes as the 3D SWE multislice images. The ablation volumes were also estimated by gross pathological examination of the livers, and the results were then compared with those obtained by 3D SWE. RESULTS In B-mode US images, the ablation zone appeared as a hypoechoic area with a peripheral hyperechoic rim; however, the findings were too indistinct to be useful for estimating the ablation area. 3D SWE depicted the ablation area and volume more clearly. In the images showing the largest ablation area, the mean kPa values of the peripheral rim, central zone, and non-ablated zone were 13.1 ± 1.5 kPa, 59.1 ± 21.9 kPa, and 4.3 ± 0.8 kPa, respectively. The ablation volumes depicted by 3D SWE correlated well with those estimated from gross pathological examination (r (2) = 0.9305, P = 0.00001). The congestion and diapedesis of red blood cells observed in histopathological examination were greater in the peripheral rim of the ablation zone than in the central zone. CONCLUSION 3D SWE outperforms B-mode US in delineating ablated areas in the liver and is therefore more reliable for spatially delineating thermal lesions created by RF ablation.