Single-use duodenoscope for ERCP performed by endoscopists with a range of experience in procedures of variable complexity.

BACKGROUND AND AIMS: Expert endoscopists previously reported ERCP outcomes for the first commercialized single-use duodenoscope. We aimed to document usability of this device by endoscopists with different levels of ERCP experience. METHODS: Fourteen "expert" (>2000 lifetime ERCPs) and 5 "less-expert" endoscopists performed consecutive ERCPs in patients without altered pancreaticobiliary anatomy. Outcomes included ERCP completion for the intended indication, rate of crossover to another endoscope, device performance ratings, and serious adverse events. RESULTS: Two hundred ERCPs including 81 (40.5%) with high complexity (American Society for Gastrointestinal Endoscopy grades 3-4) were performed. Crossover rate (11.3% vs 2.5%, P = .131), ERCP completion rate (regardless of crossovers) (96.3% vs 97.5%, P = .999), median ERCP completion time (25.0 vs 28.5 minutes, P = .130), mean cannulation attempts (2.8 vs 2.8, P = .954), and median overall satisfaction with the single-use duodenoscope (8.0 vs 8.0 [range, 1.0-10.0], P = .840) were similar for expert versus less-expert endoscopists, respectively. The same metrics were similar by procedural complexity except for shorter median completion time for grades 1 to 2 versus grades 3 to 4 (P < .001). Serious adverse events were reported in 13 patients (6.5%). CONCLUSIONS: In consecutive ERCPs including high complexity procedures, endoscopists with varying ERCP experience had good procedural success and reported high device performance ratings. (Clinical trial registration number: NCT04223830.).

Two-photon polymerization nanofabrication of ultracompact light scattering spectroscopic probe for detection of pre-cancer in pancreatic cyst.

Pancreatic cancer has one of the worst survival rates of all major cancers, with pancreatic cystic lesions accounting for one in three pancreatic surgeries. The current gold-standard for diagnosis of pancreatic cyst malignancy is based on the endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) procedure, which suffers from a low accuracy in detecting malignancy. Here we present the design and two-photon polymerization based fabrication of refractive and reflective non-contact probes, capable of rapid surveillance of the entire internal cyst surface-an advance over the contact probe we recently developed that allowed, for the first time, reliable evaluation of pancreatic cyst malignant potential in vivo. We employed a novel two-photon polymerization technique, which allows direct laser-writing to an accuracy of tens of nanometers, to fit the probe within the 540 micrometer internal diameter EUS-FNA needle. The newly constructed probes show excellent separation of the illumination and collection beams, essential for proper operation of the spatial gating method. These probes can be used clinically to perform rapid "optical biopsy", ultimately eliminating unnecessary pancreatic surgeries on benign cysts and dangerous delays in surgical removal of malignant cysts, improving patient prognosis and quality of life.

In vivo detection of bile duct pre-cancer with endoscopic light scattering spectroscopy.

Bile duct cancer is the second most common primary liver cancer, with most diagnoses occurring in the advanced stages. This leads to a poor survival rate, which means a technique capable of reliably detecting pre-cancer in the bile duct is urgently required. Unfortunately, radiological imaging lacks adequate accuracy for distinguishing dysplastic and benign biliary ducts, while endoscopic techniques, which can directly assess the bile duct lining, often suffer from insufficient sampling. Here, we report an endoscopic optical light scattering technique for clinical evaluation of the malignant potential of the bile duct. This technique employs an ultraminiature spatial gating fiber optic probe compatible with cholangioscopes and endoscopic retrograde cholangiopancreatography (ERCP) catheters. The probe allowed us to investigate the internal cellular composition of the bile duct epithelium with light scattering spectroscopy (LSS) and phenotypic properties of the underlying connective tissue with diffuse reflectance spectroscopy (DRS). In a pilot in vivo double-blind prospective study involving 29 patients undergoing routine ERCP procedures, the technique detected malignant transformation with 97% accuracy, showing that biliary duct pre-cancer can be reliably identified in vivo non-invasively.

Use of fully covered self-expanding metal biliary stents for managing endoscopic biliary sphincterotomy related bleeding.

Background and study aims Endoscopic biliary sphincterotomy (EBS) related-bleeding is a common adverse event related to endoscopic retrograde cholangiopancreatography (ERCP). Traditionally, endoscopic modalities such as epinephrine injection, cauterization, and balloon tamponade have been used for management. Recently, use of a fully covered self-expandable metal stent (FCSEMS) to manage EBS-related bleeding has gained popularity. However, data regarding its use are limited to small case series. Therefore, we aimed to evaluate the safety and efficacy of FCSEMS placement for the treatment of EBS-related bleeding. Patients and methods All patients referred to our center from October 2014 to November 2019 who had an FCSEMS placed for EBS-related bleeding were included. FCSEMS was placed either for primary control of bleeding or after failure of other traditional endoscopic hemostasis techniques at the discretion of the endoscopist. Data was collected regarding patient demographics, procedural characteristics, clinical and technical success rates of FCSEMS, as well as adverse events. Results A total of 97 patients underwent placement of FCSEMS for EBS-related bleeding, of which 76.3 % had immediate bleeding and 23.7 % had delayed bleeding. Mean age was 67.2 years and 47.4 % were males. Seven patients who had immediate EBS-related bleeding at index ERCP underwent other endoscopic therapies prior to placement of FCSEMS for rebleeding. The technical success rate for FCSEMS placement was 100 % and the rebleeding rate was 6.2 %. Four patients with FCSEMS placement developed pancreatitis and four had stent migration. Conclusions Our findings suggest that FCSEMS is a highly effective treatment modality for managing EBS-related bleeding and has an acceptable safety profile.

Training a computer-aided polyp detection system to detect sessile serrated adenomas using public domain colonoscopy videos.

Background Colorectal cancer (CRC) is a major public health burden worldwide, and colonoscopy is the most commonly used CRC screening tool. Still, there is variability in adenoma detection rate (ADR) among endoscopists. Recent studies have reported improved ADR using deep learning models trained on videos curated largely from private in-house datasets. Few have focused on the detection of sessile serrated adenomas (SSAs), which are the most challenging target clinically. Methods We identified 23 colonoscopy videos available in the public domain and for which pathology data were provided, totaling 390 minutes of footage. Expert endoscopists annotated segments of video with adenomatous polyps, from which we captured 509 polyp-positive and 6,875 polyp-free frames. Via data augmentation, we generated 15,270 adenomatous polyp-positive images, of which 2,310 were SSAs, and 20,625 polyp-negative images. We used the CNN AlexNet and fine-tuned its parameters using 90 % of the images, before testing its performance on the remaining 10 % of images unseen by the model. Results We trained the model on 32,305 images and tested performance on 3,590 images with the same proportion of SSA, non-SSA polyp-positive, and polyp-negative images. The overall accuracy of the model was 0.86, with a sensitivity of 0.73 and a specificity of 0.96. Positive predictive value was 0.93 and negative predictive value was 0.96. The area under the curve was 0.94. SSAs were detected in 93 % of SSA-positive images. Conclusions Using a relatively small set of publicly-available colonoscopy data, we obtained sizable training and validation sets of endoscopic images using data augmentation, and achieved an excellent performance in adenomatous polyp detection.