Objective: Endoscopic retrograde cholangiopancreatography (ERCP) may be unsuccessful in patients with duodenal stenosis or malignant ampullary infiltration. Endoscopic ultrasound-guided biliary drainage (EUS-BD) has been proposed as an alternative. We aimed to assess the efficacy and safety of EUS-BD for malignant distal bile duct obstruction using the newly introduced smaller caliber 6 or 8 mm cautery-enhanced lumen-apposing metal stent. Methods: A multicenter retrospective study was performed on patients with unresectable malignant distal bile duct obstruction who underwent EUS-BD between 2021 and 2022 after unsuccessful ERCP. Results: Thirty-two patients were included [7 (53.13%) males], with a mean age of 72.2 ± 12.5 years. The technical success rate was 100%. Altered anatomy was present in 2 (6.25%). The indication for drainage was biliary obstruction from pancreatic cancer in 26 patients (84.5%), cholangiocarcinoma in 3 (9.4%), and ampullary mass in 3 (9.4%). The procedure was performed mostly in an outpatient setting (n = 19, 59.38%). The clinical success rate was 92.3% [bilirubin: 14.1 (SD: 8.9) preprocedure vs 4.9 (SD: 1.1) postprocedure; P= 0.0001]. There was one early adverse event of a perforation, which was closed endoscopically and drained percutaneously. Delayed adverse events included food impaction of the stent (n = 1), which was resolved with a repeat procedure and insertion of a double pigtail stent. Conclusion: This study demonstrates the feasibility of EUS-BD drainage using smaller caliber 6 or 8 mm lumen-apposing metal stent to relieve malignant distal bile duct obstruction in patients who fail conventional ERCP.

Objectives: Pancreatic duct leaks can cause ascites, and fluid amylase can be used as a marker to suggest pancreatic duct leak; however, there is no reference parameter or cutoff value for diagnosis. We assessed whether a novel ratio of ascitic fluid to serum amylase can reliably predict pancreatic leaks and need for endoscopic retrograde cholangiopancreatography (ERCP). Materials and methods: Patients who had fluid amylase from ascitic fluid and serum amylase within one week of confirmed pancreatic leaks via ERCP were included along with appropriate medical and surgical controls. Results: A total of sixteen patients were included in the study group. The mean ascitic fluid amylase to serum amylase ratio in the study group was 243, and 0.3511, and 0.9406 for medical and surgical controls respectively. The cutoff ratio to predict pancreatic leaks was 6.89 with 100% sensitivity and specificity (p-value 0.0000000000001347). Conclusions: Patients with a fluid to serum amylase ratio of at least 6.89 should be considered high risk for pancreatic leak with consideration to proceed directly to ERCP.

Background and study aims Endoscopic retrograde cholangiopancreatography (ERCP) poses the risk of radiation exposure (RE) to patients and staff and increases the risk of adverse biological effects such as cataracts, sterility, and cancer. Newer fluoroscopy equipment (C-Arm) provides options to limit radiation in the form of lower radiation dose and frame rate or time-limited "pulsed" settings. However, the impact of lower settings on image quality has not been assessed, and no standard protocol exists for fluoroscopy settings used during ERCP. Patients and methods This was a single-center, double-blind, prospective randomized study of consecutive adult patients undergoing standard-of-care ERCP at a tertiary academic medical center. Patients were randomized into two groups: 1) standard-dose pulsed and 2) low-dose pulsed. Pulsed mode (8 fps) was defined as x-ray exposure either in the manufacturer standard-dose or low-dose settings limited to 3 seconds each time the foot-operated switch was depressed. Results Seventy-eight patients undergoing ERCP were enrolled and randomized. No difference in age, gender, or body mass index was found between the two groups. No significant difference in image quality was found between standard-dose and low-dose fluoroscopy P = 0.925). The low-dose group was exposed to significantly less radiation when compared with standard-dose P < 0.05). Fluoroscopy time (minutes) was similar in both groups (2.0 vs 1.9), further suggesting that group assignment had no impact on image quality or procedure time. Conclusions Low-dose pulsed fluoroscopy is a reliable method that substantially reduces radiation without compromising image quality or affecting procedure or fluoroscopy times. This underscores the need for standardization in ERCP fluoroscopy settings to limit radiation exposure.

University of Maryland School of Medicine, USA.

Introduction: Single-use duodenoscopes (SUDs) were developed in response to concerns for infection transmission while performing endoscopic retrograde cholangiopancreatography (ERCP) with re-usable duodenoscopes. Currently, Boston Scientific (Exalt) and Ambu (aScope) manufacture their own SUD models. While there have been multiple trials evaluating the Exalt model, limited data exists for the aScope model. Furthermore, conventional ERCP is performed with the patient in prone position and limited data exists for ERCP in supine position. In this study we evaluate patients who underwent ERCP with either Exalt or aScope SUD and compare the effectiveness and safety of the 2 models, as well as whether patient positioning has any effect on ERCP outcomes with SUD. Methods: Single-center retrospective study of consecutive adult patients undergoing ERCP with Exalt or aScope SUD between 1/2021-4/2023. Primary outcome was technical success and adverse events based on scope model as well as patient positioning. Secondary outcomes included the ASGE grade and procedural indication. Fisher’s exact test and chi-squared analysis were used to determine statistical significance between variables. Results: 109 procedures were included (56 Exalt, 53 aScope). Eighty-one cases were done in the supine position. The majority of cases were ASGE grade 2 (n=28) or grade 3 (n=45). Procedural indications and characteristics are listed in Table 1. Rates of technical success were 98.2% for Exalt and 100% for aScope with no statistically significant difference (Fisher’s test, P=1.0). Rates of peri-operative adverse events were 1.8% for Exalt (1 intrahepatic duct leak) and 0% for Ascope with no statistically significant difference (Fisher’s test, P=1.0). Rates of extended adverse events (within 10 days from procedure) were 5.4% for Exalt (1 sphincterotomy bleed, 1 pneumoperitoneum, 1 cholecystitis) and 0% for aScope with no statistically significant difference (Fisher’s test, P=0.24). Comparing ERCP’s performed in prone versus supine patient position, rates of technical success and adverse events were not statistically different. Conclusion: Our study highlights the efficacy of both SUD models. Regardless of patient positioning, there were high rates of technical success and low rates of adverse events, with no significant differences between models. Further studies are needed to determine whether our data is generalizable to ERCP performed outside of a tertiary center and to determine which clinical scenarios SUD should be utilized. Table 1. - Patient characteristics, procedural characteristics, and procedural outcomes Patient Characteristics Exalt aScope Male (%) 51 40 White (%) 64 70 African American (%) 27 28 Mean Age (years) 58 55 Mean BMI (kg/m2) 27.12 28.47 Prior ERCP (%) 62 67 Inpatient (%) 51 25* Prior Sphincterotomy (%) 65 65 Procedural Indication Exalt (n=) aScope (n=) Abnormal MRCP 3 1 Anastomotic Stricture 1 0 Bile Leak 3 6 Bile Stone 12 3 Biliary Stricture 10 6 Bismuth Stricture 4 3 CBD Stones 3 4 Cholangitis 6 0 Elevated Liver Enzymes 0 5 Jaundice 1 2 Pancreatic Duct Leak 0 1 Pancreatic Duct Stricture 0 1 Pancreatic Malignancy 1 0 Pancreatitis 4 12 Stent Exchange 6 2 Stent Removal 2 7 Procedural Characteristics Exalt aScope Patient Supine (%) 79 70 Sphincterotomy Performed (%) 39 26 Bile Duct Cannulation (%) 86 72 Pancreatic Duct Cannulation (%) 30 28 Stone Extraction (%) 34 17 Stent Placement (%) 70 76 Balloon Dilation (%) 13 25 Cholangioscopy (%) 11 4 ASGE Grade Exalt (n=) aScope (n=) 1 15 8 2 21 7 3 19 30 4 1 8 Model Number of Cases Technical Success (%) Peri-operative Adverse Event (%) Extended Adverse Event (%) Exalt 56 98.2 1.8 5.4 aScope 53 100 0 0 Patient Position Number of Cases Technical Success (%) Peri-operative Adverse Event (%) Extended Adverse Event (%) Prone 13 100 0 0 Supine 81 98.8 1.2 2.5 Lateral Decubitus 15 100 0 6.7 Extended adverse events are defined as adverse events within 10 days of procedure.*Statistically significant difference.

Abstract Fluoroscopy is increasingly used by gastroenterologists for endoscopic procedures such as endoscopic retrograde cholangiopancreatography. Unfortunately, fluoroscopy exposes patients and staff to ionizing radiation, which can cause DNA damage, cell death, genetic defects, and cancer. These adverse effects are more likely to occur with increased exposure time and higher radiation doses; therefore, all efforts to decrease exposure are helpful. In this study, we investigate the impact that updating the C-Arms in our endoscopy unit will have on radiation exposure by comparing ionizing radiation effects of the OEC 9900 Elite to the newer OEC Elite. After replicating the setup of a typical endoscopic retrograde cholangiopancreatography, ionizing radiation and energy were measured at the bedside and the head of the bed with each machine. At both positions, the newer OEC Elite C-Arm emitted less energy and ionizing radiation than the OEC 9900 Elite. Continuous imaging with OEC 9900 Elite emitted 0.12 mSv/h at the head of the bed and 0.49 mSv/h at the bedside, while the OEC Elite only emitted 0.04 mSv/h and 0.14 mSv/h, respectively. These values are measures of radiation-induced cancer risk, otherwise known as stochastic risk. The differences grow more significant when extrapolated to show radiation differences for an average procedure (approximately 8 minutes of fluoroscopy time) and the procedural volume for an entire year. In an effort to use as little radiation as possible, we see that we can significantly reduce radiation exposure to our staff by upgrading from an OEC 9900 Elite to and OEC Elite.

BACKGROUND In order to successfully manage traumatic pancreatic duct (PD) leaks, early diagnosis and operative management is paramount in reducing morbidity and mortality. In the acute setting, endoscopic retrograde cholangiopancreatography (ERCP) can be a useful, adjunctive modality during exploratory laparotomy. ERCP with sphincterotomy and stent placement improves preferential drainage in the setting of injury, allowing the pancreatic leak to properly heal. However, data in this acute setting is limited. CASE SUMMARY In this case series, a 27-year-old male and 16-year-old female presented with PD leaks secondary to a gunshot wound and blunt abdominal trauma, respectively. Both underwent intraoperative ERCP within an average of 5.9 h from time of presentation. A sphincterotomy and plastic pancreatic stent placement was performed with a 100% technical and clinical success. There were no associated immediate or long-term complications. Following discharge, both patients underwent repeat ERCP for stent removal with resolution of ductal injury. CONCLUSION These experiences further demonstrated that widespread adaption and optimal timing of ERCP may improve outcomes in trauma centers.

Although uterine leiomyosarcoma (ULMS) is a rare disease, it accounts for a significant proportion uterine cancer-related deaths due to frequent metastasis and chemoresistance. The WHO currently recognizes the conventional (spindle), myxoid, and epithelioid variants of ULMS, the latter of which is the rarest, least understood, and cited as clinically more aggressive than the other variants. Descriptions of the histologic features of epithelioid ULMS are extremely limited, and are absent from the cytology literature which has only published descriptions of conventional ULMS or epithelioid variants of other LMS primaries. Therefore, we present a unique case of metastatic epithelioid ULMS to an unusual location, the pancreas, along with its cytologic features on endoscopic ultrasound-guided fine needle aspiration not previously described including pseudoglandular arrangements, scant cytoplasm, and frequent molding.

Introduction: Colorectal adenomas and diverticular disease are often found independently on screening colonoscopy. The presence of colorectal adenomas share common risk factors with diverticular disease, including advanced age, low fiber diet and obesity. Therefore it is not surprising that colorectal adenomas have been found within diverticuli although it is not common. Case description/methods: A 61 year old woman with history of COPD initially presented for polypectomy after a 15 mm polyp was found on screening colonoscopy. Sigmoidoscopy revealed a 15 mm tubular adenomatous polyp in the sigmoid colon at the rim of a diverticulum (a). The polyp was injected with 5 mL ORISE for lesion assessment (b) and removed via a piecemeal manner with hot snare (c). Pathology revealed a tubulovillous adenoma with focal high grade dysplasia. Follow up sigmoidoscopy 10 months later showed recurrence of the lesion, now extending deep within the diverticulum (d), preventing polypectomy. The polyp was biopsied multiple times for evaluation of dysplasia or intramural carcinoma. Pathology showed tubulovillous adenoma, and a referral was made to colorectal surgery for risk assessment of laparoscopic resection. Discussion: Adenomas found within diverticuli pose a challenge to be managed endoscopically. Due to the lack of a muscular layer within the diverticulum, endoscopic intervention of these adenomas carries a greater risk for colonic perforation. Both diverticuli and adenomas concurrently increase in prevalence with increasing age. It is important to examine diligently during colonoscopy since high grade lesions, as in this patient, can arise in locations difficult to visualize and resect. Furthermore, progression to colon cancer of these intradiverticular lesions in case reports have been shown to have challenging complications including fistula formation. Our case highlights the need for developing a safe and effective technique for endoscopic management, which will be paramount in helping patients avoid the need for surgical management.Figure 1.: A: 15 mm tubular sigmoid adenomatous polyp at the rim of a diverticulum. B: Polyp injected with 5 mL ORISE for lesion assessment. C: Polyp after removal with hot snare. D: Recurrent sigmoid polyp extending deep within the diverticulum.

Background/Aim: Endoscopic retrograde cholangiopancreatography (ERCP) training requires varying degrees of staff assistance regarding operation of the fluoroscopy machine via a foot pedal. Efficiency is important to acquire during this training due to radiation risks. In this study, we evaluate the effect of controlling endoscopy and fluoroscopy unit on duct cannulation rates (CRs) and total fluoroscopy time (FT) for fellows in training.Methods: 204 patients undergoing ERCP were randomized to one of two groups: 1) “Endoscopist Driven” group in which the endoscopist controlled the foot pedal for fluoroscopy, and 2) “Assistant Driven” group in which attending or fellow controlled the foot pedal while the other team member controlled the endoscope. Various measures including selective duct CR and total FT were recorded.Results: There was no significant difference in mean procedure duration between the two groups (32 minutes vs. 33 minutes, p=0.70). There was also no statistically significant difference in CR (83.7% vs. 77.4%, p=0.25) or FT (3.27 minutes vs. 3.54 minutes, p=0.48).Conclusions: ERCP is a technically challenging procedure which requires extensive supervision. This study demonstrates that CR and FT are not affected by who controls the fluoroscopy.

BACKGROUND:Over 6 million esophagogastroduodenoscopy (EGD) procedures are performed in the United States each year. Patients having anesthesia for advanced EGD procedures, such as interventional procedures, are at high risk for hypoxemia. METHODS:Our primary study aim was to evaluate whether high-flow nasal cannula (HFNC) oxygen reduces the incidence of hypoxemia during anesthesia for advanced EGD. Secondarily, we studied whether HFNC oxygen reduces hypercarbia or hypotension. After obtaining written informed consent, adults having anesthesia for advanced EGD, expected to last longer than 15 minutes, were randomly assigned to receive HFNC oxygen or standard nasal cannula (SNC) oxygen. The primary outcome was occurrence of one or more hypoxemia events during anesthesia, defined by arterial oxygen saturation <92% for at least 15 consecutive seconds. Secondary outcomes were occurrence of one or more hypercarbia or hypotension events. A hypercarbia event was defined by a transcutaneous CO2 measurement 20 mm Hg or more above baseline, and a hypotension event was defined by a mean arterial blood pressure measurement 25% or more below baseline. RESULTS:Two hundred seventy-one adult patients were enrolled and randomized, and 262 patients completed study procedures. Eight randomized patients did not complete study procedures due to changes in their anesthesia or endoscopy plan. One patient was excluded from analysis because their procedure was aborted after 1 minute. Patients who received HFNC oxygen (N = 132) had a significantly lower incidence of hypoxemia than those who received SNC oxygen (N = 130; 21.2% vs 33.1%; hazard ratio [HR] = 0.59 [95% confidence interval {CI}, 0.36-0.95]; P = .03). There was no difference in the incidence of hypercarbia or hypotension between the groups. The HR for hypercarbia with HFNC oxygen was 1.29 (95% CI, 0.89-1.88; P = .17), and the HR for hypotension was 1.25 (95% CI, 0.86-1.82; P = .25). CONCLUSIONS:HFNC oxygen reduces the incidence of hypoxemia during anesthesia for advanced EGD and may offer an opportunity to enhance patient safety during these procedures.

INTRODUCTION: Fluoroscopy guidance is widely employed in the field of gastroenterology, particularly by advanced endoscopists for ERCP. This comes with the risk of ionizing radiation. Ionization can cause DNA damage and cell death, leading to cancer and genetic defects. The longer the radiation exposure and the higher the radiation levels, the more likely one is to experience these consequences. Thus, the Nuclear Regulatory Commission (NRC) set an occupational dose limit of 50 Millisievert (mSv) effective dose per year. This study investigates the effect that updating our C-Arm will have on radiation exposure by comparing ionizing radiation effects of the OEC 9900 Elite to the newer OEC Elite. METHODS: We replicated the room positioning of a typical ERCP with a C-Arm adjacent to our bed and a stack of acrylic plates to simulate patient tissue. We measured energy output and levels of radiation in the air at bedside, 33” from the center of the bed (position of endoscopist), and at the head of the table, 46” from the center of the bed (position of anesthetist). The same set-up and measurements were completed with the OEC 9900 Elite and the OEC Elite. For each system and position we calculated mSv/hr with continuous and pulsed fluoroscopy. RESULTS: At each position, the OEC Elite emitted less energy and ionizing radiation or potential for radiation-induced harm than the OEC 9900 Elite. Continuous imaging with OEC 9900 Elite emitted 0.12 mSv/hr at the head of the bed and 0.49 mSv/hr at the bedside, while the OEC Elite emitted 0.04 mSv/hr and 0.14 mSv/hr, respectively. CONCLUSION: This study confirms that the greater the distance a staff member stands from the location that x-rays enter the patient, the lower their radiation exposure will be. Similarly, pulsed imaging mode lowers scatter radiation exposure. Unique to this study, is the demonstration that the OEC Elite operated at a lower energy output (kVp and mA), which resulted in lower scatter radiation exposure. With an average of 8 minutes of fluoroscopy time per ERCP and approximately 850 ERCP cases done annually in our endoscopy center, the annual effective dose is strongly influenced by C-Arm choice. Continuous fluoroscopy imaging with OEC 9900 Elite produces 13.92 mSv/year at the head of the bed and 55.60 mSv/year at the bedside. However, the OEC Elite produces 4.18 mSv/year and 15.41 mSv/year at respective locations and would allow an endoscopist standing at bedside for these cases to remain within NRC occupational dose limit of 50 mSv annually.Table 1.: Depicts the energy output in kVp and mA as well as the measurement of radiation in a volume of air (mR/hr) for each device, image mode, and location. kVp = Kilovoltage peak; mA = Milliamperage; mR/hr = Milliroentgen per hourTable 2.: Depicts stochastic biological risk of ionizing radiation in rates of Millisievert, which is the commonly used SI (International System of Units) measurement. Shown above in rates per hour, case, and year. In this study, a case represents 8 minutes of fluoroscopy time, which is the average per ERCP. A year consists of 850 ERCP cases, which is the approximate ERCP case load in our Endoscopy Center at UMMCImage 1.: Demonstrates the experimental set-up used to simulate an endoscopic case with fluoroscopic guidance. Here, a Fluke 451 Ion Chamber Survey Meter is used to measure ionizing radiation from bedside at typical position of endoscopist.

INTRODUCTION: Gastric cancer is the fifth most common cancer and the third leading cancer-related death worldwide. It is reported that up to 22% of gastric cancers can be missed when evaluating synchronous lesions, and generally around 10% of gastric cancers are missed. In this case report, we discuss a diagnosis of gastric adenocarcinoma that was discovered via small balloon enteroscopy. CASE DESCRIPTION/METHODS: A 57-year-old female was referred for an evaluation of symptomatic iron deficiency anemia and melena. She had prior EGD and colonoscopy less than a year prior to presentation that were negative for any bleeding lesions. A repeat colonoscopy a few months later did show multiple polyps with no bleeding site. The patient continued to have melena thus a capsule endoscopy was performed; this showed active bleeding in the small intestine. The patient then underwent a single-balloon enteroscopy that showed normal duodenum and jejunum (Figure 1). On retraction of the scope, however, the patient had a small focal area of a moderately erythematous mucosa with hematin on the anterior wall (lesser curvature) of the mid-gastric body (Figure 2). This was biopsied and pathology was positive for a poorly differentiated adenocarcinoma with predominant signet ring cell features (Figure 3). She was diagnosed with stage T3 lymph node positive signet ring adenocarcinoma and underwent surgical treatment. She is planned to start adjuvant chemotherapy. DISCUSSION: As with other malignancies, earlier detection of gastric cancer leads to better prognosis. In this case, the patient was undergoing an evaluation for a small bowel lesion when a previously missed upper GI lesion was found via balloon enteroscopy. This case highlights the importance of a persistent and complete work up of a patient’s symptoms, especially in the setting of initial negative endoscopic results.Figure 1.: Normal jejunum.Figure 2.: Focal area of erythema and hemorrhage in the gastric body.Figure 3.: Pathology of the bleeding lesion showing poorly differentiated adenocarcinoma with predominant signet ring cell features, magnified ×400.

Hepatobiliary and esophageal malignancies are often complicated by obstructions that warrant palliative endoscopic stenting. Patients also often undergo radiotherapy as a standard treatment, but there are concerns that metallic stents could affect the amount of radiation dose delivered. There is limited current literature on the proton dose effects on newer esophageal and biliary stents. This study aims to analyze and compare the radiation dosimetry effects of esophageal and biliary stents to determine if dose adjustments are needed in the areas where the stents are placed. Five esophageal and seven biliary stents were used in this study from multiple manufacturers. Esophageal stents included covered and partially covered models of 18 mm diameter. Biliary stents studied included covered and uncovered models of 10 mm diameter, a 6 mm covered stent and 7 Fr plastic stent. The water equivalent thickness (WET) values of each sample were obtained by measuring the shift in the proton beam range through each stent using a multi-layer ionization chamber (MLIC; Giraffe, IBA Dosimetry, Germany) as shown in Figure 1. Proton beams were then delivered simultaneously to the stents inside a water phantom. The 2D-planar dose was measured with a MatriXX PT detector array (IBA Dosimetry, Germany) as seen in Figure 2. WET values for all esophageal stents were less than 1mm, ranging from 0.35 to 0.85 mm. WET values of all biliary stents were less than 0.5mm, ranging from 0.15 to 0.4 mm. The plastic stent had a WET value of 1.55mm. For planar dose measurements in water, no difference (less than 1%) was observed for both esophageal and biliary stents implying that the perturbation effect of the stents is within the measurement uncertainty and not detectable. The stents' WET values indicate the change in the proton beam range due to the presence of the stent is negligible. Our study's results show that the presence of biliary and esophageal stents resulted in minimal proton radiation dose perturbation of less than 1%Figure 22D planar dose measurement setup using MatriXX PT detector array.View Large Image Figure ViewerDownload Hi-res image Download (PPT)