Woo Hyun Paik

Simplified fistula dilation technique and modified stent deployment maneuver for EUS-guided hepaticogastrostomy

AIM To evaluate the success rates, procedural time and adverse event rates of the modified methods in endoscopic ultrasonography-guided hepaticogastrostomy (EUS-HGS). METHODS Twenty-eight patients in a prospective case series who underwent EUS-HGS (phase I). Forty-six patients in a matched case-control study (phase II). The simplified technique for fistula dilation was the primary use of a 4 mm balloon catheter with a stainless steel stylet. The stent deployment was modified by deploying the metal stent inside a bile duct (half of the stent) under EUS and fluoroscopic guidance and gently pulling the echoendoscope after full deployment of the stent inside the echoendoscope channel (remaining portion of the stent) under fluoroscopic guidance. This cohort was compared with a matched historical cohort. RESULTS In phase I, the technical and clinical success with the modified method was 96% (27/28) and 89% (24/27 as per-protocol analysis). The overall adverse event rate was 7%. In phase II, there was no difference in technical and clinical success, stent patency and overall adverse events in each group. However, the procedural time (15.3 ± 5.2 min vs 22.3 ± 6.0 min, P < 0.001) and early adverse events (0% vs 26%, P = 0.02) were statistically improved in case cohort compared with control cohort. CONCLUSION Compared with the conventional EUS-HGS technique, the procedural time was shorter and early adverse events were less frequent with our simplified and modified technique.

Prospective evaluation of new 22 gauge endoscopic ultrasound core needle using capillary sampling with stylet slow-pull technique for intra-abdominal solid masses.

Goals: The aim of this study was to evaluate the adequacy and diagnostic yield of the histologic core obtained with a 22 G endoscopic ultrasound histology needle using capillary sampling with stylet slow-pull technique without on-site cytopathologist. Background: No standard technique for new EUS histology needle has been established. Study: A total of 125 consecutive patients with intra-abdominal solid masses were enrolled prospectively between October 2011 and March 2013. EUS-guided fine needle biopsy (EUS-FNB) with a 22 G histology needle using capillary sampling with stylet slow-pull technique was performed. Results: A total of 133 EUS-FNB procedures targeting the pancreas, lymph node, retroperitoneal mass, ampulla of Vater, gallbladder, common bile duct, duodenum, and liver were performed in 125 patients. EUS-FNB was technically feasible in all cases, and a visible core was obtained in 128 cases (96%). Histologic core specimens suitable for pathologic assessment were reported in 111 cases (83%). There were no procedure-related adverse events. According to the determinants of malignancy with EUS-FNB, the sensitivity, specificity, positive and negative predictive values, and accuracy were 85%, 98%, 99%, 77%, and 89%, respectively. In addition, histologic architecture with or without immunohistochemical staining of the core biopsy specimens was useful for pathologic confirmation in 101 cases (76%). Conclusions: A 22 G EUS-FNB using capillary sampling with stylet slow-pull technique showed a high diagnostic yield and histologic core acquisition for the histologic diagnosis of various intra-abdominal masses without an on-site cytopathologist. Furthermore, a histologic core with or without immunohistochemical staining was helpful for clinical decision making in 76% of the intra-abdominal solid masses.

Clinical relevance of the revised Atlanta classification focusing on severity stratification system

BACKGROUND/OBJECTIVE Recognizing the limitation of the Atlanta classification for acute pancreatitis (AP), two international classifications have been recently proposed; the revised Atlanta classification and the determinant-based classification. There is an inconsistency between the two international classifications on whether infected necrosis (IN) is the major determinant of severity in AP. The aim of the current study was to validate the revised Atlanta classification and to determine the association of this new classification system with relevant clinical outcome in patients with AP. METHODS Data have been collected on 553 patients with AP admitted to a single center during the 7-year period commencing January 2006. Primary outcomes included the need for interventions, the need for intensive care unit (ICU) care, length of ICU stay, total hospital stay, and mortality. RESULTS The different grades of severity for revised Atlanta classification system were associated with statistically significant differences in terms of clinical outcomes. Patients with severe AP that had IN, compared to those without IN, were associated with worse clinical outcomes. Having stratified patients with severe AP category according to the presence or absence of IN, the mortality rate increased fourfold to 32.3% for the presence of infected necrosis. CONCLUSIONS Overall, the revised Atlanta classification seems to be valid, since it correlates well with clinical outcome. To more accurately assess clinical outcome of patients with severe AP defined by the revised Atlanta classification, however, severe AP patients with IN should be considered separately from those without IN in classification system.

Conversion of external percutaneous transhepatic biliary drainage to endoscopic ultrasound-guided hepaticogastrostomy after failed standard internal stenting for malignant biliary obstruction

Background and study aim Percutaneous transhepatic biliary drainage (PTBD) is a rescue procedure after a failed endoscopic retrograde cholangiopancreatography. As PTBD causes patient discomfort, conversion of the PTBD to internal biliary stenting (PTBDS) may be required; however, PTBDS is sometimes difficult because of the tight stricture. We evaluated the efficacy and safety of conversion of external PTBD to endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) after failed PTBDS. Patients and methods A total of 16 patients with malignant distal biliary obstruction who underwent conversion of external PTBD to EUS-HGS after failed PTBDS were enrolled from two institutions in Korea and Japan. Data were analyzed retrospectively. Results The technical and clinical success rates were 100 % and 81 %, respectively. Early adverse events developed in two patients: proximal stent migration (n = 1), and cholecystitis (n = 1). Stents were occluded or migrated distally in five patients. The mean duration of stent patency was 402 days. Conclusions Conversion of external PTBD to EUS-HGS may be a good rescue option after failed PTBDS.

Clinical usefulness with the combination of color Doppler and contrast-enhanced harmonic EUS for the assessment of visceral vascular diseases.

Goals: To evaluate the clinical usefulness of the color Doppler and contrast-enhanced harmonic endoscopic ultrasonography (CEH-EUS) in diagnosing visceral vascular diseases and in assessing morphologic and hemodynamic characteristics required for optimized patient management. Background: Mesenteric arteries are easily accessible with EUS because of its proximities to the gastrointestinal tract. Study: EUS was performed in 12 patients with clinically suspected visceral vascular disease, as determined by computed tomography (CT) scan between February 2012 and March 2013. Conventional B-mode, color Doppler, and CEH-EUS was performed to evaluate vascular status of the celiac artery and superior mesenteric artery (SMA). Results: CT scan imaging suggested arterial dissection in 9 patients; arterial stenosis or occlusion in 2 patients, and periarterial soft tissue cuffing in 1 patient. EUS accurately identified all the visceral vascular lesions of 11 patients and 1 patient with suspected SMA dissection on CT imaging was proven to be normal by EUS. EUS also identified one undefined dissection not detected on abdominal CT. EUS examination revealed vascular intimal flap in 5 patients and blood flow within the true lumen and thrombi within the false lumen in 8 patients. In addition, the stenotic area could be calculated using color Doppler EUS. Two patients underwent surgical thrombectomy and angioplasty because of total occlusion of SMA on color Doppler and CEH-EUS. Conclusions: The combination of color Doppler and CEH-EUS may be a promising diagnostic modality to assess the splanchnic artery without exposure to radiation. Moreover, EUS is a useful tool to determine the appropriate treatment options for patients with isolated mesenteric artery dissection.

Endoscopic Ultrasound-Guided Biliary Access, with Focus on Technique and Practical Tips

In 1980, endoscopic ultrasound (EUS) was introduced as a diagnostic tool for evaluation of the pancreas. Since the introduction of curvilinear-array echoendoscopy, EUS has been used for a variety of gastrointestinal interventions, including fine needle aspiration, tumor ablation, and pancreatobiliary access. One of the main therapeutic roles of EUS is biliary drainage as an alternative to endoscopic retrograde biliary drainage (ERBD) or percutaneous transhepatic biliary drainage (PTBD). This article summarizes three different methods of EUS-guided biliary access, with focus on technique and practical tips.

UTILITY OF ENDOSCOPIC ULTRASOUND (EUS)-GUIDED FINE-NEEDLE ASPIRATION FOR PERI-ARTERIAL SOFT TISSUE CUFFS WITHOUT IDENTIFIABLE PANCREAS MASS ON CT AND EUS: A PROSPECTIVE COMPARATIVE STUDY

Pancreatic cancer may present as a peri-arterial soft tissue cuff (PSTC) around the superior mesenteric artery or celiac axis without an identifiable pancreatic mass. We evaluated the diagnostic yield of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in patients with a PSTC without definite pancreas involvement and those with a typical pancreatic mass. The patients who underwent EUS-FNA of a PSTC without pancreatic involvement were prospectively enrolled. The patients who underwent EUS-FNA for a pancreatic mass were recruited as a control group. A total of 224 patients underwent 247 EUS-FNAs. Among the 13 patients with a PSTC, 11 were positive for malignancy as determined by EUS-FNA, with 5 diagnosed after the first session and 6 after the second session. The diagnostic yield of PSTCs by EUS-FNA was significantly lower than that for typical pancreatic masses (65% vs. 87%, p = 0.02). An on-site cytopathologist and repeated EUS-FNA are recommended to improve the diagnostic accuracy of this disease entity.