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Browsing by Author "Wallace, Michael B."
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Item Clip Closure Prevents Bleeding After Endoscopic Resection of Large Colon Polyps in a Randomized Trial(Elsevier, 2019-10) Pohl, Heiko; Grimm, Ian S.; Moyer, Matthew T.; Hasan, Muhammad K.; Pleskow, Douglas; Elmunzer, B. Joseph; Khashab, Mouen A.; Sanaei, Omid; Al-Kawas, Firas H.; Gordon, Stuart R.; Mathew, Abraham; Levenick, John M.; Aslanian, Harry R.; Antaki, Fadi; von Renteln, Daniel; Crockett, Seth D.; Rastogi, Amit; Gill, Jeffrey A.; Law, Ryan J.; Elias, Pooja A.; Pellise, Maria; Wallace, Michael B.; Mackenzie, Todd A.; Rex, Douglas K.; Medicine, School of MedicineBackground & aims: Bleeding is the most common severe complication after endoscopic mucosal resection of large colon polyps and is associated with significant morbidity and cost. We examined whether prophylactic closure of the mucosal defect with hemoclips after polyp resection reduces the risk of bleeding. Methods: We performed a multicenter, randomized trial of patients with a large nonpedunculated colon polyp (≥20 mm) at 18 medical centers in North America and Spain from April 2013 through October 2017. Patients were randomly assigned to groups that underwent endoscopic closure with a clip (clip group) or no closure (control group) and followed. The primary outcome, postprocedure bleeding, was defined as a severe bleeding event that required hospitalization, a blood transfusion, colonoscopy, surgery, or another invasive intervention within 30 days after completion of the colonoscopy. Subgroup analyses included postprocedure bleeding with polyp location, polyp size, or use of periprocedural antithrombotic medications. We also examined the risk of any serious adverse event. Results: A total of 919 patients were randomly assigned to groups and completed follow-up. Postprocedure bleeding occurred in 3.5% of patients in the clip group and 7.1% in the control group (absolute risk difference [ARD] 3.6%; 95% confidence interval [CI] 0.7%-6.5%). Among 615 patients (66.9%) with a proximal large polyp, the risk of bleeding in the clip group was 3.3% and in the control group was 9.6% (ARD 6.3%; 95% CI 2.5%-10.1%); among patients with a distal large polyp, the risks were 4.0% in the clip group and 1.4% in the control group (ARD -2.6%; 95% CI -6.3% to -1.1%). The effect of clip closure was independent of antithrombotic medications or polyp size. Serious adverse events occurred in 4.8% of patients in the clip group and 9.5% of patients in the control group (ARD 4.6%; 95% CI 1.3%-8.0%). Conclusions: In a randomized trial, we found that endoscopic clip closure of the mucosal defect following resection of large colon polyps reduces risk of postprocedure bleeding. The protective effect appeared to be restricted to large polyps located in the proximal colon.Item Endoscopic Ultrasound and Related Technologies for the Diagnosis and Treatment of Pancreatic Disease - Research Gaps and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop(Lippincott, Williams & Wilkins, 2017) Lee, Linda S.; Andersen, Dana K.; Ashida, Reiko; Brugge, William R.; Canto, Mimi I.; Chang, Kenneth J.; Chari, Suresh T.; DeWitt, John; Hwang, Joo Ha; Khashab, Mouen A.; Kim, Kang; Levy, Michael J.; McGrath, Kevin; Park, Walter G.; Singhi, Aatur; Stevens, Tyler; Thompson, Christopher C.; Topazian, Mark D.; Wallace, Michael B.; Wani, Sachin; Waxman, Irving; Yadav, Dhiraj; Singh, Vikesh K.; Medicine, School of MedicineA workshop was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases to address the research gaps and opportunities in pancreatic endoscopic ultrasound (EUS). The event occurred on July 26, 2017 in 4 sessions: (1) benign pancreatic diseases, (2) high-risk pancreatic diseases, (3) diagnostic and therapeutics, and (4) new technologies. The current state of knowledge was reviewed, with identification of numerous gaps in knowledge and research needs. Common themes included the need for large multicenter consortia of various pancreatic diseases to facilitate meaningful research of these entities; to standardize EUS features of different pancreatic disorders, the technique of sampling pancreatic lesions, and the performance of various therapeutic EUS procedures; and to identify high-risk disease early at the cellular level before macroscopic disease develops. The need for specialized tools and accessories to enable the safe and effective performance of therapeutic EUS procedures also was discussed.Item EUS-derived criteria for distinguishing benign from malignant metastatic solid hepatic masses(Elsevier, 2015-05) Fujii-Lau, Larissa L.; Abu Dayyeh, Barham K.; Bruno, Marco J.; Chang, Kenneth J.; DeWitt, John M.; Fockens, Paul; Forcione, David; Napoleon, Bertrand; Palazzo, Laurent; Topazian, Mark D.; Wiersema, Maurits J.; Chak, Amitabh; Clain, Jonathan E.; Faigel, Douglas O.; Gleeson, Ferga C.; Hawes, Robert; Iyer, Prasad G.; Rajan, Elizabeth; Stevens, Tyler; Wallace, Michael B.; Wang, Kenneth K.; Levy, Michael J.; Medicine, School of MedicineBackground Detection of hepatic metastases during EUS is an important component of tumor staging. Objective To describe our experience with EUS-guided FNA (EUS-FNA) of solid hepatic masses and derive and validate criteria to help distinguish between benign and malignant hepatic masses. Design Retrospective study, survey. Setting Single, tertiary-care referral center. Patients Medical records were reviewed for all patients undergoing EUS-FNA of solid hepatic masses over a 12-year period. Interventions EUS-FNA of solid hepatic masses. Main Outcome Measurements Masses were deemed benign or malignant according to predetermined criteria. EUS images from 200 patients were used to create derivation and validation cohorts of 100 cases each, matched by cytopathologic diagnosis. Ten expert endosonographers blindly rated 15 initial endosonographic features of each of the 100 images in the derivation cohort. These data were used to derive an EUS scoring system that was then validated by using the validation cohort by the expert endosonographer with the highest diagnostic accuracy. Results A total of 332 patients underwent EUS-FNA of a hepatic mass. Interobserver agreement regarding the initial endosonographic features among the expert endosonographers was fair to moderate, with a mean diagnostic accuracy of 73% (standard deviation 5.6). A scoring system incorporating 7 EUS features was developed to distinguish benign from malignant hepatic masses by using the derivation cohort with an area under the receiver operating curve (AUC) of 0.92; when applied to the validation cohort, performance was similar (AUC 0.86). The combined positive predictive value of both cohorts was 88%. Limitations Single center, retrospective, only one expert endosonographer deriving and validating the EUS criteria. Conclusion An EUS scoring system was developed that helps distinguish benign from malignant hepatic masses. Further study is required to determine the impact of these EUS criteria among endosonographers of all experience.Item Quality Assurance of Computer-Aided Detection and Diagnosis in Colonoscopy(Elsevier, 2019) Vinsard, Daniela Guerrero; Mori, Yuichi; Misawa, Masashi; Kudo, Shin-ei; Rastogi, Amit; Bagci, Ulas; Rex, Douglas K.; Wallace, Michael B.; Medicine, School of MedicineRecent breakthroughs in artificial intelligence (AI), specifically via its emerging sub-field “Deep Learning,” have direct implications for computer-aided detection and diagnosis (CADe/CADx) for colonoscopy. AI is expected to have at least 2 major roles in colonoscopy practice; polyp detection (CADe) and polyp characterization (CADx). CADe has the potential to decrease polyp miss rate, contributing to improving adenoma detection, whereas CADx can improve the accuracy of colorectal polyp optical diagnosis, leading to reduction of unnecessary polypectomy of non-neoplastic lesions, potential implementation of a resect and discard paradigm, and proper application of advanced resection techniques. A growing number of medical-engineering researchers are developing both, CADe and CADx systems, some of which allow real-time recognition of polyps or in vivo identification of adenomas with over 90% accuracy. However, the quality of the developed AI systems as well as that of the study designs vary significantly, hence raising some concerns regarding the generalization of the proposed AI systems. Initial studies were conducted in an exploratory or retrospective fashion using stored images and likely overestimating the results. These drawbacks potentially hinder smooth implementation of this novel technology into colonoscopy practice. The aim of this article is to review both contributions and limitations in recent machine learning based CADe/CADx colonoscopy studies and propose some principles that should underlie system development and clinical testing.Item Valuing innovative endoscopic techniques: prophylactic clip closure after endoscopic resection of large colon polyps(Elsevier, 2020) Shah, Eric D.; Pohl, Heiko; Rex, Douglas K.; Wallace, Michael B.; Crockett, Seth D.; Morales, Shannon J.; Feagins, Linda A.; Law, Ryan; Medicine, School of MedicineBackground and Aims Clip closure of the mucosal defect after resecting large (≥20 mm) nonpedunculated colorectal polyps reduces postprocedure bleeding and is cost saving for payers. Clip costs are not reimbursed by payers, posing a major barrier to adoption of this technique in the community. We aimed to determine appropriate clip costs to support broader use of this procedure in practice. Methods We performed budget impact analysis using our recent decision analytic model, comparing prophylactic clip closure with no clip closure on national cost and outcomes data, to determine the maximum feasible clip price while maintaining cost savings in practice. Sensitivity analyses were performed on important clinical factors. Results In the original model, the baseline postprocedure bleeding risk was 6.8%, increasing cost of care by $614.11 averaged among all patients undergoing large polyp resection without clip closure. Prophylactic clip closure of only large right-sided polyps reduced postprocedure bleeding risk by 70.7% but resulted in cost saving only if the price of clips was $100 or less. Comparatively, prophylactic clip closure of large left-sided polyps had no clinical benefit and was not cost saving. Clip closure strategies focused only on extra-large polyps (≥40 mm), or patients taking antithrombotics regardless of polyp characteristics, were only minimally cost saving. Cost savings and maximum tolerated clip prices depended on medical comorbidity, which directly influences the costs of care to manage postprocedure bleeding. Conclusions Prophylactic clip closure after endoscopic resection of large colon polyps, particularly those in the right colon segment, is cost saving but requires clip costs less than $100. Translating these findings into practice requires gastroenterology practices to obtain reimbursement from payers for improved clinical outcomes and to align commercial clip prices with this clinical indication.