19G FNA Research Articles

Temporary EUS-Guided Hepaticogastrostomy With Electrohydraulic Shockwave Lithotripsy for Management of Altered Anatomy Choledocholithiasis: 2017 Presidential Poster Award

ERCP is challenging in patients with gastric bypass due to altered anatomy. We report a case of symptomatic choledocholithiasis requiring temporary placement of EUS-guided hepaticogastrostomy with a fully covered metal stent and electrohydraulic lithotripsy. This is a 71-year-old female with a history of multiple abdominal surgeries, including Roux-en-Y gastric bypass with Fobi pouch, appendectomy, cholecystectomy, and adhesiolysis who presented with 4 months right upper quadrant abdominal pain and a 1 week hx of jaundice. MRCP revealed intra and extrahepatic ductal dilatation with a 1.1cm obstructing stone in a tortuous CBD. A double balloon enteroscopy assisted ERCP was considered but initial endoscopy revealed a stricture at the GJ anastomosis thought to be related to complications from the fobi pouch. Given the complex anatomy, surgery was consulted to coordinate a laparoscopic-assisted ERCP. However, due to her extensive surgical history and multiple repeated open abdominal surgeries, they strongly advocated for a non-surgical approach. Interventional radiology was then consulted for a percutaneous approach, but explained that they would require multiple procedures for percutaneous tract dilation before the point that stone extraction could be attempted. As a result, an EUS guided approach was performed via creation of a hepaticogastrostomy. The procedure was performed by puncturing a dilated radical of the left intrahepatic system with a 19G FNA needle. A 0.035mm guidewire was passed antegrade down into the tortuous bile duct. A 6mm balloon catheter was passed into the bile duct and used to dilate the tract. A 10mmx8cm fully covered metal biliary stent was placed from the gastric pouch to the intrahepatic ducts with confirmation made with cholangiogram. A pediatric gastroscope was then passed through the stent and eventually into the distal CBD where the stone was seen. Under direct visualization saline assisted electrohydraulic shockwave lithotripsy was performed to fragment the stone. The stone pieces were pushed and flushed through the ampulla. Two months later, patient underwent repeat EGD. The stent was subsequently removed without any complications and today she continues to do well. This case illustrates that lithotripsy through a temporarily placed EUS-guided hepaticogastrostomy may be safe and effective approach for altered anatomy patients who cannot undergo more traditional approaches for management of complex choledocholithiasis.Figure: MRCP Showing 10.4mm CBD Stone.Figure. CBD: Stone Before Lithotripsy.Figure. CBD: Stone After Lithotripsy.

Needle-Based Confocal Laser Endomicroscopy for Evaluation of Cystic Neoplasms of the Pancreas.

The accurate diagnosis of cystic neoplasms of the pancreas (CNP) with current diagnostic methods is limited. Endoscopic ultrasound (EUS)-guided needle-based confocal laser endomicroscopy (nCLE) is a new technique which can obtain images from the cyst wall during EUS-fine needle aspiration (EUS-FNA). The aim of this study was to assess the safety, feasibility, and diagnostic value of nCLE for CNP. Patients who underwent EUS-FNA to evaluate a CNP larger than 2cm were enrolled. The cyst was punctured with 19-G FNA needle preloaded with an nCLE probe. The images from different areas of the cyst wall were recorded. Using the final diagnosis defined by surgery or EUS-FNA cyst fluid analysis, the accuracy of the confocal images was defined. The procedure and image acquisition was successful in 18 of the 20 patients. Predefined typical structures for mucinous cysts were visualized in 8 of 12 (66%) cysts but none of the non-mucinous cysts. The superficial vascular network which is a typical finding of serous cysts was observed in 2 of 3 patients. The sensitivity, specificity, and diagnostic accuracy of the findings of epithelial structures by nCLE were 66, 100, and 80%, respectively, for a mucinous cyst diagnosis. All patients tolerated the procedure well, and no adverse effects were determined. nCLE was found to be safe and feasible with high technical success, in this pilot study. With an overall accuracy of 80%, it has the potential to contribute to the diagnosis of CNP with specific imaging.

Optimizing EUS-guided liver biopsy sampling: comprehensive assessment of needle types and tissue acquisition techniques

EUS-guided liver biopsy sampling using FNA and, more recently, fine-needle biopsy (FNB) needles has been reported with discrepant diagnostic accuracy, in part due to differences in methodology. We aimed to compare liver histologic yields of 4 EUS-based needles and 2 percutaneous needles to identify optimal number of needle passes and suction. Six needle types were tested on human cadaveric tissue: one 19G FNA needle, one existing 19G FNB needle, one novel 19G FNB needle, one 22G FNB needle, and two 18G percutaneous needles (18G1 and 18G2). Two needle excursion patterns (1 vs 3 fanning passes) were performed on all EUS needles. Primary outcome was number of portal tracts. Secondary outcomes were degree of fragmentation and specimen adequacy. Pairwise comparisons were performed using t tests, with a 2-sided P< .05 considered to be significant. Multivariable regression analysis was performed. In total, 288 liver biopsy samplings (48 per needle type) were performed. The novel 19G FNB needle had significantly increased mean portal tracts compared with all needle types. The 22G FNB needle had significantly increased portal tracts compared with the 18G1 needle (3.8 vs 2.5, P< .001) and was not statistically different from the 18G2 needle (3.8 vs 3.5, P= .68). FNB needles (P< .001) and 3 fanning passes (P≤ .001) were independent predictors of the number of portal tracts. A novel 19G EUS-guided liver biopsy needle provides superior histologic yield compared with 18G percutaneous needles and existing 19G FNA and core needles. Moreover, the 22G FNB needle may be adequate for liver biopsy sampling. Investigations are underway to determine whether these results can be replicated in a clinical setting.

EUS-guided intrahepatic portosystemic shunt with direct portal pressure measurements: a novel alternative to transjugular intrahepatic portosystemic shunting

Transjugular intrahepatic portosystemic shunting involves the creation of a low-resistance channel between the portal vein (PV) and the hepatic vein (HV), and is routinely performed under angiography. The aims were to evaluate (1) safety and technical feasibility; (2) procedural duration; and (3) subjective workload assessment of EUS-guided intrahepatic portosystemic shunt (EIPS). Five Yorkshire pigs were used in the study. The HV or inferior vena cava (IVC) was identified using a linear-array echoendoscope and accessed with a 19-G FNA needle preloaded with a digital pressure wire. Mean pressure was recorded. The needle was advanced into the PV, where pressure measurements were again taken, and ultimately exchanged over a guidewire. A lumen-apposing metal stent was deployed under EUS and fluoroscopic guidance, with distal and proximal ends positioned inside the PV and HV (IVC),respectively. Dilation was performed, and pressure measurements repeated. The National Aeronautics and Space Administration (NASA) Task Load Index (TLI) was scored. Animals survived 2 weeks before necropsy. EIPS was successful in 5 out of 5 pigs. Mean time required for EUS identification, needle access, pressure measurement, and stent placement was 43 (31-55) minutes. NASA TLI scores revealed moderate workload. Mean baseline pressure measurements were PV 7.0 (5-9) and HV/IVC 5.0 (3-7)mm Hg and PV 6.3 (5-7) and HV/IVC 6.0 (4-7)mm Hg after. All animals survived 2 weeks. No bleeding was seen on necropsy. This study demonstrates the technical feasibility of EIPS using LAMS, with direct portal pressure measurement, in a survival model. In addition, the procedure was performed quickly with moderate technical demand.

Comparison of 22G reverse-beveled versus standard needle for endoscopic ultrasound-guided sampling of solid pancreatic lesions.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) using standard needles has a high diagnostic value in the evaluation of solid pancreatic masses. Fenestrated needles have been developed to improve the quality of EUS-guided tissue sampling by providing core biopsies (FNB). Patients with solid pancreatic masses of >2 cm were prospectively included in our study and randomized to receive EUS sampling, using either a standard 22G FNA or a 22G Procore® FNB needle. The main study endpoint was the number of needle passes required to obtain a diagnosis in more than 90% of cases. We included 100 patients (male = 63, female = 37; mean age = 68.4 years) in our study. We found that 88% of the lesions were malignant, with a mean size of 32 mm. A sample adequate for diagnosis was obtained in more than 90% of cases after the second needle pass in the FNB group, versus the third needle pass in the FNA group. Slide cellularity and presence of tissue microfragments were significantly higher in the FNB group. Sensitivity for the diagnosis of malignancy was 88.4% versus 97.8% for the EUS-FNA and EUS-FNB group, respectively, while specificity for both techniques was 100%. No complications were recorded. Although the accuracy of both needle types for proving malignancy was similar, a lower number of passes was required with the FNB needles to achieve the same contributive sample rate as with the FNA needles. FNB also improved the histopathological quality of specimens, suggesting an overall superiority of FNB sampling.

PWE-210 Needle-based confocal laser endomicrosocpy for pancreatic cystic lesions: initial results from the UK concyst study

<h3>Introduction</h3> Pancreatic cystic lesions (PCL) are an increasingly common clinical finding, present in up to 2% of patients undergoing CT and 14% of those undergoing MRI for non-pancreatic indications. Cytology from endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) often has a low diagnostic yield. Needle-based confocal laser endomicroscopy (nCLE) allows a sub-millimetre AQ-flex 19 miniprobe (Mauna Kea Technologies, Paris, France) to be inserted into the cyst via a 19G FNA needle, enabling real-time imaging of the interior of the cyst. The aim of the study was therefore to evaluate the diagnostic potential, safety and efficacy of nCLE in the management of indeterminate PCL. <h3>Method</h3> The CONCYST study aims to recruit 60 patients prospectively with indeterminate CLP who require EUS-FNA from hepatopancreaticobiliary referral centres with nCLE in the UK; currently Royal Free Hospital, London, and Addenbrooke’s Hospital, Cambridge. The study commenced in July 2014; 21 patients have been recruited to date. The procedure was performed under conscious sedation (Midazolam and Fentanyl). Patients received antibiotics immediately prior to the start of the procedure. 2.5mls of 10% fluorescein was injected once the cyst was visualised at EUS. After observation in the recovery room for up to 4 h all patients were discharged home the same day. Following the procedure all patients were followed up by telephone clinic. Ethical approval for the study was granted by the National Research Ethics Service (14/LO/0040). <h3>Results</h3> Of the 21 patients that underwent EUS-nCLE, 12 were male and 9 female. Median age was 70 (range 40–86) years. Confocal images were obtained in all cases. Median nCLE scanning time was 5 min and did not exceed 10 min in any case. EUS-nCLE findings correlated with final diagnosis (based on imaging, cytology and multidisciplinary team review) in 91% (19/21) of cases which was superior to cytology alone which correlated with final diagnosis in 71% (15/21) of cases. One patient experienced mild pruritus immediately following the procedure (possibly related to the fluorescein injection) but this settled promptly with a single dose of chlorphenamine. No complications were reported during follow-up. <h3>Conclusion</h3> These preliminary results are encouraging and suggest that nCLE under conscious sedation in the daycase setting is safe. Our initial findings indicate that EUS-nCLE is more sensitive than standard EUS-FNA for diagnosing indeterminate cystic lesion of the pancreas, but larger numbers will be required to confirm these findings. <h3>Disclosure of interest</h3> None Declared.

935 A Novel EUS-Guided Liver Biopsy Needle Is Superior to 19-G Core and FNA Needles: Examining the Effect of Needle Design, Number of Excursions, and Variable Suction Parameters on Histologic Yield

935 A Novel EUS-Guided Liver Biopsy Needle Is Superior to 19-G Core and FNA Needles: Examining the Effect of Needle Design, Number of Excursions, and Variable Suction Parameters on Histologic Yield

Which needle is better for diagnosing subepithelial lesions?

Which needle is better for diagnosing subepithelial lesions?

Basic technique in endoscopic ultrasound-guided fine needle aspiration for solid lesions: How many passes?

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has evolved to become an indispensable tool for tissue acquisition in patients with luminal and extra luminal gastrointestinal cancers. Despite the extensive use of EUS-FNA, there still exists a wide variation in the number of samples required to ensure acquisition of diagnostic material from different kind of lesions. There are several factors that may influence the number of fine needle passes made during EUS-FNA, but the main factor seems to be the presence of a Cytopathologist during the EUS procedure. The diagnostic yield of EUS-FNA with rapid on-site evaluation (ROSE) in most studies exceeds 90%. Nevertheless, ROSE is not available in many centers. Various studies have investigated the adequate number of needle passes that should be performed if ROSE is not used. Differences exist based on the nature of the target lesion: Five to seven passes for pancreatic masses, three passes for lymphnodes, only one pass for pancreatic cystic lesions. Consider using a core biopsy needle or a 19-G FNA needle for histology could improve the diagnostic yield. Even though EUS-FNA is widely available, some patients still do not receive conclusive diagnoses upon initial EUS-FNA. One way to maximize the benefits for patients might be to centralize cases to several well-equipped, high-volume centers with experienced endosonographers that have universal availability of ROSE.

Mo1501 Meta-Analysis Comparing Rates of Complications Between the Standard 19G and 22G/25G Needles for EUS-Guided FNA of Pancreatic Lesions

With recent technological advancements 19G needles are increasingly being used for EUS-guided FNA procedures. However, given the limited number of studies, differences in needle designs, and heterogeneity in lesions sampled, there is scant data on the safety profile of the standard 19G FNA needle for tissue acquisition and cyst aspiration.

329 Reduced Expression of Nerve Growth Factor in Aging Gastric Mucosal Endothelial Cells - A New Key Mechanism for Impaired Angiogenesis in Aging Gastric Mucosa?

croscopy (CLE) is a novel tool that enables in-vivo histologic imaging by detection of fluorescence. An ultrathin CLE catheter probe that inserts into a 19G FNA needle now allows for Needle-based confocal laser endomicroscopy (nCLE). This study was aimed to determine feasibility of in vivo visualization of the innervation of porcine pancreas using endoscopic ultrasound guided nCLE and a fluorescent neuronal marker; and to determine pancreatic nerve cell expression of: nerve growth factor (NGF neurotrophic factor that promotes survival of neuronal cells), its high affinity receptor Trk A and melatonin receptor 1 (MR1). Methods. Studies were performed in anesthetized pigs. NeuroTrace (fluorescent neuronal marker) was injected into pancreas tail and body using endoscopic ultrasound guided 19G FNA needle, followed by nCLE in vivo imaging (Cellvizio AQ-Flex-19, Mauna Kea Technologies, Paris, France). Pigs were then euthanized and pancreatic specimens obtained for histology, ex-vivo immunostaining and molecular imaging. Studies: 1) nCLE image analysis, 2) quantitative histology and visualization of neuronal labeling under fluorescence, 3) immunostaining and quantification for NGF, its TrkA receptor and MR1 using specific antibodies. Results: nCLE imaging visualized an extensive network of intrapancreatic ganglia and nerves labeled with NeuroTrace. There was a higher density of neural elements in the body than the tail. On histologic sections examined under fluorescence microscope, in-vivo injected NeuroTrace was localized to the neural structures and nerves in pancreatic stromal tissue with features similar to those seen on nCLE. NGF was strongly expressed in intrapancreatic neuronal cells and nerves and was also expressed in epithelial cells of pancreatic acini and endothelial cells of blood vessels. TrkA was expressed in some neuronal cells and nerves distributed throughout the acini. MR1 was expressed in about 60% of ganglion cells and nerves and also in pancreatic acini. Quantitatively its expression was 2.5fold lower (p,0.01) compared to NGF. Conclusions: 1)This study showed feasibility of in vivo visualization of neuronal network in porcine pancreas nCLE. 2)The pancreatic neural network is extensive; numerous neuronal cells express NGF, Trk A and MTR1. 3)NGF and MR1 expression in epithelial acinar cells and endothelium of blood vessels, in addition to neural structures, indicates local interactions between neural, epithelial and vascular components of pancreas.

Diagnosis of Pancreatic Cysts: Endoscopic Ultrasound, Through-the-needle Confocal Laser-induced Endomicroscopy and Cystoscopy Trial (DETECT Study)

Purpose: Probe-based confocal laser-induced endomicroscopy (pCLE) enables in-vivo real time GI tract imaging. A prototype high-resolution CLE probe has been developed (Cellvizio, Mauna Kea Technologies), which inserts into a 19G FNA needle allowing for needle-based CLE (nCLE). The diagnosis of pancreatic cysts, which now depends on morphology, cytology and fluid analysis, is challenging. The combination of direct visualization (cystoscopy) using a through-the-needle fiber optic probe (Spyglass, Boston Scientific) and nCLE under EUS guidance may improve the diagnosis of pancreatic cysts.The aim of this study (NCT#01447238) was to determine the feasibility and safety of EUS-guided dual “through-the-needle” imaging (cystoscopy and nCLE) and to identify specific imaging features which correlate with mucinous vs. non-mucinous cysts. Methods: After EUS examination, the cyst was punctured with a 19G FNA needle (Cook Medical) preloaded with a fiber optic probe. After examination of the cyst wall and contents, the probe was exchanged with nCLE probe and in vivo imaging was performed after IV injection of 2.5 ml fluorescein. Both exams were performed by advancing the probe just beyond the needle tip. Finally, fluid was aspirated and string sign, cytology, CEA and amylase evaluated. Clinical diagnosis was based on surgical pathology or clinical presentation combined with EUS findings, CT/MRI, cytology and fluid analysis (independent blinded review). Results: From October 2010 to May 2012, 30 patients with pancreatic cysts were enrolled (Table 1). Clinical diagnosis was “high certainty” in 18 (IPMN-7, MCN-3, SCN-4, pseudocyst-3, lymphoepithelial cyst-1) and “less certain” in 12 (IPMN-7, SCN-4, retention cyst-1). Needle puncture, probe advancement, and image acquisition was successful in all 30 cases; 29 via single puncture. Two patients developed pancreatitis requiring 4-day hospitalizations. The image quality of cystoscopy and nCLE was good/excellent in 20 (67%) and 27 (90%) cases, respectively. Cystoscopy and nCLE findings of mucinous vs. non-mucinous cysts in cases with high certainty diagnosis (2 surgical, 16 clinical) are shown in Table 2. Mucin on cystoscopy and epithelial structures on nCLE were specific (100%) to mucinous cysts and presence of debris on cystoscopy was specific (100%) to non-mucinous cysts. Sensitivity for mucinous cysts using: cystoscopy (mucin) alone, nCLE (epithelial structures) alone, and cystoscopy + nCLE was 90%, 80%, and 100% respectively.Table 1: Patient characteristics and FNA resultsTable 2: FNA results and image findings on cystoscopy and nCLE in mucinous and non-mucinous lesions and their sensitivity, specificity, PPV and NPV for mucinous cystsConclusion: EUS-FNA with through-the-needle cystoscopy and nCLE for pancreatic cysts appears safe and feasible, and specific features were identified which appear to predict the clinical diagnosis of mucinous vs. non-mucinous cysts. Additional data confirming histologic correlation is needed. Disclosure: Dr. Chang - consultant for Olympus, Wilson Cook. Dr. Samarasena - None. Dr. Nakai - None. Dr. Iwashita - None. Dr. Lee - None. Dr. Park - None.

Novel Use of Endoscopic Ultrasound to Successfully Treat Parastomal Varices with N-butyl-2-cyanoacrylate: Presidential Poster

Purpose: Describe a novel role for endoscopic ultrasound (EUS) in the treatment of parastomal varices with N-butyl-2-cyanoacrylate (NBCA). Case Report: A 74 year old female with a hx of ulcerative colitis s/p colectomy with end ileostomy, morbid obesity, COPD (O2 dependent), and Laennec's cirrhosis was transferred to our institution for transfusion dependent ostomy bleeding. The patient had over a dozen admissions to her local hospital and required 34 units of PRBC over the last year. CT demonstrated parastomal varices with cirrhotic liver morphology. Two previous attempts at transjugular intrahepatic portosystemic shunt (TIPS) were unsuccessful due to adverse anatomy. Options were discussed with the patient. A trial of beta-blockers was thought suboptimal given her COPD. A retrial of TIPS at our institution was offered but the patient refused. Consequently, we decided to employ EUS to localize the parastomal varices and then use NBCA to obliterate them. The patient was prepped with Mg citrate overnight. First, an adult gastroscope was advanced 20 cm into the stoma. No blood was seen and the mucosa was normal with no large vessels. Subsequently, a radial echoendoscope was used to visualize two prominent parastomal varices below the mucosal surface of the ileostomy by US. Flow was confirmed with Doppler. A linear echoendoscope was then inserted. Using a 22-G FNA needle, a mixture of 0.5 ml NBCA and 1.5 ml lipoidal was injected into the varices with good immediate effect. Lack of flow was confirmed after injection by Doppler. Ex-vivo, needle and scope channel were immediately flushed with Lipoidol. A total of 5.5 ml of glue was used. The patient tolerated the procedure well, was discharged home after 3 days, and has had no further episodes of bleeding. Discussion: Parastomal varices are a known complication of stoma creation in patients with portal HTN. Established treatments for parastomal varices include TIPS and surgery. We describe a case of parastomal varices in a patient who could not undergo either of these treatment modalities. Additionally, her significant comorbidities were a relative contraindication to even medical therapy with beta-blockers. Consequently, we employed EUS-guided NBCA glue to treat her parastomal varices. Though a few cases of parastomal varices treated with glue exist in the literature, all of the previous situations have employed a direct percutaneous approach. Consequently, this is the first reported case where EUS is successfully used for visualization and obliteration of varices in this patient population. Although further evaluation is warranted, EUS appears to be a safe and important adjunct modality in the treatment of stomal varices by NBCA glue injection.

Assessment of the technical performance of the flexible 19-gauge EUS-FNA needle

A needle made of nitinol has been developed with enhanced flexibility to overcome the limitations of the currently available 19-G EUS-FNA needles. Evaluate the ability to perform transduodenal FNAs, procure histologic specimens, and undertake therapeutic interventions using the flexible 19-G needle. Prospective cohort study. Tertiary-care academic medical center. Consecutive patients with subepithelial masses, pancreatic head or uncinate lesions, or lesions adjacent to the pancreatic head, and patients undergoing therapeutic intervention. Perform tissue acquisition and interventions with the flexible 19-G FNA needle. Evaluate the ability to perform transduodenal passes with the flexible 19-G FNA needle. Also, assess the utility of the needle to yield both cytologic and histologic samples and to perform therapeutic interventions. Of the 50 patients enrolled, tissue acquisition was undertaken in 38 and therapeutic intervention in 12. Of 38 patients from whom tissue was procured, 32 tissue samples were from pancreatic head/uncinate or peripancreatic masses and 6 were from subepithelial masses. Tissue acquisition, which included transduodenal passes, was successful and adequate for cytologic assessment in all 38 patients (100%). Satisfactory histologic specimens were procured from 36 of 38 (94.7%) patients. An onsite diagnosis was established in 35 of 38 (92.1%) patients. In 3 patients with indeterminate/suspicious lesions, a definitive diagnosis was established at histology. A mean of 1.45 ± 0.79 passes per patient was performed. All 12 therapeutic interventions were successful (100%) and included pseudocyst drainage in 5, pelvic abscess drainage in 2, fiducial placement in 2, celiac plexus neurolysis in 2, and cholangiogram in 1. Needle dysfunction or procedural complications were not encountered. Single-center study with limited power. Preliminary data suggest that the flexible 19-G needle can be used for procuring cytologic aspirates and histologic specimens and to undertake therapeutic interventions even by the transduodenal route. Confirmatory studies are required in a larger cohort of patients with varied pathologic conditions to validate these findings.

Randomized trial comparing the 22-gauge aspiration and 22-gauge biopsy needles for EUS-guided sampling of solid pancreatic mass lesions

To overcome limitations of cytology, biopsy needles have been developed to procure histologic samples during EUS. To compare 22-gauge (G) FNA and 22G biopsy needles (FNB) for EUS-guided sampling of solid pancreatic masses. Randomized trial. Tertiary-care medical center. This study involved 56 patients with solid pancreatic masses. Sampling of pancreatic masses by using 22G FNA or 22G FNB devices. Compare the median number of passes required to establish the diagnosis, diagnostic sufficiency, technical performance, complication rates, procurement of the histologic core, and quality of the histologic specimen. A total of 28 patients were randomized to the FNA group and 28 to the FNB group. There was no significant difference in median number of passes required to establish the diagnosis (1 [interquartile range 1-2.5] vs 1 [interquartile range 1-1]; P = .21), rates of diagnostic sufficiency (100% vs 89.3%; P = .24), technical failure (0 vs 3.6%; P = 1.0), or complications (3.6% for both) between FNA and FNB needles, respectively. Patients in whom diagnosis was established in passes 1, 2, and 3 were 64.3% versus 67.9%, 10.7% versus 17.9%, and 25% versus 3.6%, respectively, for FNA and FNB cohorts. There was no significant difference in procurement of the histologic core (100% vs 83.3%; P = .26) or the presence of diagnostic histologic specimens (66.7% vs 80%; P = .66) between FNA and FNB cohorts, respectively. Only pancreatic masses were evaluated. Diagnostic sufficiency, technical performance, and safety profiles of FNA and FNB needles are comparable. There was no significant difference in yield or quality of the histologic core between the 2 needle types.

Tu1524 Endoscopic Ultrasound Guided Transmural Drainage (Eutmd) for Walled off Pancreatic Necrosis (WOPN) - a Single Center Experience of 65 Patients

Endoscopic Ultrasound Guided Transmural Drainage (Eutmd) for Walled off Pancreatic Necrosis (WOPN) a Single Center Experience of 65 Patients Advay Aher*, Amol Bapaye Dept. of Digestive Diseases & Endoscopy, Deenanath Mangeshkar Hospital & Research Center, Pune, India Introduction & Aim: WOPN defined as a walled off collection of pus, necrotic debris & enzyme rich fluid in the lesser sac, is a frequent sequel of acute severe pancreatitis. WOPN may be infected or sterile. Infected WOPN is the commonest cause of sepsis & intervention in these patients. Intervention may be percutaneous, surgical or endoscopic with or without EUS guidance. Controversy exists regarding the best approach. We present a retrospective analysis of outcomes of 66 consecutive patients of WOPN treated by EUTMD over 7 years (2005-11). Patients & Methods: Median age was 38 years (Range 19 62); 57 (86%) males. Etiology of pancreatitis was gall stones 42 (64%), alcohol 17 (26%) & others 7 (10%). Sepsis (42, 64%) was the commonest indication for intervention; followed by failure to tolerate enteral feeds & severe abdominal pain. Contrast enhanced spiral CT scan confirmed suitability of endoscopic drainage based on location, wall thickness & contents. Visual quantification of necrosis by EUS excluded 5 patients (8%, 50% solid debris). EUTMD was performed in the rest. After EUS guided puncture using 19G FNA needle, tract was dilated to 18mm over a guide wire & multiple stents were placed. Same session endoscopic necrosectomy was performed when EUS showed 25% solid debris, additional nasocystic drain (NCD) was placed & cavity irrigated. Procedure was repeated till debris was cleared; NCD was removed & multiple stents left in place. Intravenous antibiotics were prescribed throughout hospitalization. Follow up was at 1, 2, 4 & 6 weeks using appropriate imaging. ERP & pancreatic sphincterotomy was performed between 2 to 4 weeks, duct stents were placed to bridge leak or into the cavity in case of disconnection. Observations & Results: 61/66 (92%) patients underwent EUTMD. Balloon dilation (18mm) was performed in all. Median 4 (2-5) stents placed. Necrosectomy was performed in 29/61 (48%), NCD & irrigation in 29/29 (100%), median 2 (1-4) sessions. Median hospital stay was 8 (4-65) days. Complications were seen in 23/61 (37.7%) patients aggravation of infection in 11 (18%), hemorrhage in 5 (8.1%, 2 surgery, 1 endoclips, 2 self limiting), residual intra abdominal (IA) fluid collections in 7 (11.4%). Subsequent surgery was required in 20/61 (32.7%). 4(6.5%) patients died of ongoing post-operative sepsis. ERP & sphincterotomy was performed in 38/61 (62.3%). Stents were placed in 26/38 (68.4%), 20 (84.3%) in cavity, 6 (15.7%) bridging the leak. Conclusions: EUTMD is an effective treatment for most WOPN patients. Aggressive approach of large balloon dilation, necrosectomy (for 25% solid debris), multiple stent placement & ERP with pancreatic duct stenting may avoid surgery in two thirds patients. Complications can occur in one third patients & nearly always demand surgery.

Sa1538 Usability and Cytological Yield of a Rotatable, Rapid Exchange 19G FNA Needle vs. Standard 19G FNA Needle in 3 Echoendoscope Positions

Sa1538 Usability and Cytological Yield of a Rotatable, Rapid Exchange 19G FNA Needle vs. Standard 19G FNA Needle in 3 Echoendoscope Positions

EUS-guided needle-based Confocal Laser induced Endomicroscopy (nCLE): a correlation study of “through the needle' imaging with normal histology in a porcine model

Background: Endoscopic probe-based Confocal Laser Endomicroscopy (pCLE) enables in-vivo real time imaging of cells and blood flow within the mucosal layer of the GI tract. Recently, a prototype high-resolution CLE probe has been developed (Cellvizio®, Mauna Kea Technologies) which can be introduced through a 19g FNA needle creating the possibility for needle-based Confocal Laser Endomicroscopy (nCLE). The feasibility and quality of images obtained using EUS-guided nCLE in solid organs such as the pancreas, liver, spleen, gallbladder and lymph node have not been clearly correlated with normal histology.

EUS-Guided Placement of Fiducial Markers Using a 22-Gauge Needle

Background: Image guided radiotherapy requires precise mapping of the therapeutic field such that maximal therapy can be applied to cancer tissue while minimizing toxicity to adjacent organs. In soft tissue tumors of the chest, abdomen and pelvis, implantation of radiographic markers (fiducials) is required to construct reference points. Endoscopic ultrasound is routinely employed as a safe and reliable means of staging and sampling many common gastrointestinal malignancies. Limited reports have described EUS-guided placement of fiducials with 19G FNA needles. However no data exists on the feasibility of fiducial placement with a 22G FNA needle. Aims: Describe the feasibility, success and safety of EUS guided fiducial placement with a 22 G FNA needle in GI malignancies and associated lymph nodes. Methods: Patients presenting for EUS evaluation of esophageal malignancies and subsequently found to have nodal positive disease were enrolled. EUS guided fiducial placement was utilized to demarcate the proximal and/or distal most extend of tumor burden. All underwent linear EUS by a single endosonographer. Visicoil gold cylindrical fiducials (0.35 mm X 10 mm) were inserted into tumor or nodal tissue using a standard 22G FNA needle. The cylindrical gold fiducial was manually inserted into the hollow channel of a 22G needle and kept in place with sterile bone wax such that when the tip of the needle was inserted into the target lesion, advancement of the stylet would results in the manual insertion of the fiducial under real time EUS visualization. The position of the fiducial was verified by EUS. Chart review was performed at two months for evaluation of complications. Demographic data including patient age, gender, and cancer stage were collected. Results: Four patients, median age 60 years, all with esophageal cancer (3 adenocarcinoma, 1 squamous) and nodal involvement had fiducials placed. A total of 1-2 fiducials were attempted for each patient. EUS guided fiducial placement was successful in 4/4 patients (100%). Locations of fiducial placed included celiac node (2) AP window node (2) gastrohepatic node (1) and esophagus (2). None of the patients had complications (perforation or infection) within two months of placement. 100% of fiducials attempted were appropriately placed in target site. In all patients (2) with available pretreatment CT scans, 100% of fiducials placed were easily identifiable. Conclusion: A standard 22G FNA needle is effective in directing fiducials into endoscopically accessible malignant nodes and esophageal cancer. This technique is feasible and safe and can be of benefit in mapping tumor extent for radiotherapy.

Is Endoscopic Ultrasound Guided Brachytherapy (EUS-BrTx) Useful for the Treatment of Recurrent Malignant Lymph Nodes?

Background: Brachytherapy is an established treatment for various cancers such as head and neck, lung, and most commonly prostate cancer. For GI malignancies, brachytherapy has been used for esophageal, pancreatic and rectal cancer. Although it has many advantages (minimal toxicity to surrounding organs, single session delivery, etc) one of its major limitations is delivery access. EUS-guided Brachytherapy (EUS-BrTx) is a newly reported technique. However, outcomes data is limited. We report our experience with EUS-BrTx in 5 patients with recurrent cancer. Patient and Method: Four patients with esophageal cancer and one patient with duodenal cancer had pathologically confirmed recurrent malignant lymph nodes. EUS-BrTx was performed as part of an IRB approved protocol using 19G FNA needle (Cook Medical Inc, Bloomington, IN)) and either iodine I125 or palladium Pd103 seeds. Four patients required only a single session while one patient underwent four sessions for recurrent LNs over a span of 9 months. A total of 11 LNs were treated. Two patients had chemotherapy following EUS-BrTx. Result: All LNs were successfully implanted with radioactive seeds via EUS without any procedure related complications. The median size of LNs was 16.2 x 10.5 mm(range 9.5 x 8.2 - 35.9 x 37.0mm). The median number of implanted seeds was 3.5 (1 - 12). On follow up EUS or CT, seven out of 11 LNs(63.6 %) showed decrease in size or disappearance. Two out of 11 LNs (18.2%) did not change in size and 2 out of 11 LNs(18.2%) showed increase in size. Three patients are still alive without any signs of recurrence with a mean survival of 11 months from time of EUS-BrTx. Conclusion: EUS-BrTx is a safe and feasible procedure with an 82% control rate for locally recurrent LNs in a small series.