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Introduction: To investigate the impact of procedure-related and endoscopist-related factors on the effectiveness of a computer-aided detection (CADe) device in adenomas per colonoscopy (APC) detection., Methods: The SKOUT clinical trial was conducted at 5 US sites. We present prespecified analyses of procedure-related and endoscopist-related factors, and association with APC across treatment and control cohorts., Results: There were numeric increases in APC between SKOUT vs standard colonoscopy in community-based endoscopists, withdrawal time of ≥8 minutes, for endoscopists with >20 years of experience, and endoscopists with baseline adenoma detection rate <45%., Discussion: The application of CADe devices in clinical practice should be carefully evaluated. Larger studies should explore differences in endoscopist-related factors for CADe., (Copyright © 2023 by The American College of Gastroenterology.)

Objectives: Risk stratification in Barrett's esophagus (BE) is challenging. We evaluated the ability of a panel of genetic markers to predict progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC)., Methods: In this case-control study, we assessed a measure of genetic instability, the mutational load (ML), in predicting progression to HGD or EAC. Cases had nondysplastic BE or low-grade dysplasia (LGD) at baseline and developed HGD/EAC ≥1 year later. Controls were matched 2:1, had nondysplastic BE or LGD, and no progression at follow-up. Formalin-fixed, paraffin-embedded tissue was microdissected for the epithelium. Loss of heterozygosity (LOH) and microsatellite instability (MSI) were assessed. ML was calculated from derangements in 10 genomic loci. High-clonality LOH mutations were assigned a value of 1, low-clonality mutations were assigned a value of 0.5, and MSI 0.75 at the first loci, and 0.5 for additional loci. These values were summed to the ML. Receiver operator characteristic (ROC) curves were created., Results: There were 69 patients (46 controls and 23 cases). Groups were similar in age, follow-up time, baseline histology, and the number of microdissected targets. Mean ML in pre-progression biopsies was higher in cases (2.21) than in controls (0.42; P<0.0001). Sensitivity was 100% at ML ≥0.5 and specificity was 96% at ML ≥1.5. Accuracy was highest at 89.9% for ML ≥1. ROC curves for ML ≥1 demonstrated an area under the curve (AUC) of 0.95., Conclusions: ML in pre-progression BE tissue predicts progression to HGD or EAC. Although further validation is necessary, ML may have utility as a biomarker in endoscopic surveillance of BE.

Objectives: Thrombosis of the portal venous system (PVS) may complicate cirrhosis, pancreatitis, malignancies, and hypercoagulable states. Computed tomography (CT) scanning can diagnose thrombi present in the lumen of the PVS, but is probably insensitive. Endoscopic ultrasound (EUS) may be a more sensitive test for diagnosing PVS thrombosis (PVST). We sought to determine the accuracy of EUS for the diagnosis of PVST., Methods: Using a retrospective analysis of patients' studies retrieved from a database at Massachusetts General Hospital, we determined the sensitivity and specificity of EUS in 16 patients with PVST and 29 without PVST as proven by surgery and/or CT scanning. All patients underwent a linear EUS exam of the PVS and the results of the EUS report were used as the basis of the study., Results: The sensitivity of EUS for the finding of PVST was 81% in 13 of 16 patients and the specificity was 93% in 27 of 29 patients with an overall accuracy of 89% (40/45). In an additional group of 11 patients, EUS demonstrated the presence of a PVST that was not detected by CT scanning., Conclusion: Linear EUS is a highly sensitive and specific test for PVST.

Bile leaks are the most common biliary complication of laparoscopic cholecystectomy. Cholescintigraphy has been utilized in the past to diagnose postoperative bile leaks after open cholecystectomy. However, the sensitivity and specificity of this imaging technique has not been defined or compared to other clinical tests. We have retrospectively studied 30 patients over a 2-yr period who underwent cholescintigraphy for a possible postoperative bile leak. This study reviewed the cholescintigraphy images, clinical presentations, and abdominal ultrasonography/CT scanning. Using a gold standard that consisted of the findings of cholangiography and clinical outcome, we determined the diagnostic accuracy of these tests. Symptoms, laboratory testing, and physical examination were found to be poor predictors for the presence of postoperative bile leaks. Ultrasound and CT imaging were less sensitive and nonspecific. In contrast, cholescintigraphy was found to be quite accurate (83-87%) for predicting the presence of bile leaks after laparoscopic cholecystectomy, as well as other biliary surgeries.

Many previous investigations of available amylase inhibitors have not been able to demonstrate significant carbohydrate malabsorption. This study uses breath hydrogen analysis, a sensitive method for detecting the passage of starch into the colon, to determine if a potent amylase inhibitor is capable of producing carbohydrate malabsorption. Thirteen volunteers underwent three studies, ingesting as a carbohydrate substrate: lactulose 20 g, spaghetti alone, and spaghetti with amylase inhibitor (3.8 g). Samples of breath were collected (at frequent intervals) for 2 h after the lactulose and for 8 h after the spaghetti meal and analyzed for hydrogen concentration. The ingestion of spaghetti alone resulted in significant increases in breath hydrogen concentration at 420-450 min. The mean (+/- SE) hydrogen excretion rate was increased more than 2-fold with the amylase inhibitor, from 0.4 +/- 0.2 to 0.9 +/- 0.3 ml/h (p less than 0.05). Use of the amylase inhibitor in powder form produced a similar increase in the rate of hydrogen excretion to 1.1 +/- 0.4 ml/h. The percentage of carbohydrate malabsorbed was calculated for the spaghetti meal and spaghetti with amylase inhibitor using each individual's observed hydrogen excretion with lactulose. Over the 8-h observation period, 4.7 +/- 1.9% of the spaghetti was malabsorbed and 7.0 +/- 1.4% of the spaghetti with amylase inhibitor was malabsorbed (p less than 0.05). Measurements of the effect of the amylase inhibitor on amylase activity of duodenal juice revealed that the amylase inhibitor at a concentration of more than 5 mg/ml decreased the amylase activity by more than 96%. These results indicate that this potent amylase inhibitor is capable of enhancing malabsorption of wheat starch.