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The American Society for Gastrointestinal Endoscopy (ASGE) has proposed the "resect-and-discard" and "diagnose-and-leave" strategies for diminutive colorectal polyps to reduce the costs of unnecessary polyp resection and pathology evaluation. However, the diagnostic thresholds set by these guidelines are not always met in community practice. To overcome this sub-optimal performance, artificial intelligence (AI) has been applied to the field of endoscopy. The incorporation of deep learning algorithms with AI models resulted in highly accurate systems that match the expert endoscopists' optical biopsy and exceed the ASGE recommended thresholds. Recent studies have demonstrated that the integration of AI in clinical practice results in significant improvement in endoscopists' diagnostic accuracy while reducing the time to make a diagnosis. Yet, several points need to be addressed before AI models can be successfully implemented in clinical practice. In this review, we summarize the recent literature on the application of AI for characterization of colorectal polyps, and review the current limitation and future directions for this field., (Copyright © 2021. Published by Elsevier Ltd.)

In response to the coronavirus disease 2019 (COVID-19) pandemic, many jurisdictions and gastroenterological societies around the world have suspended nonurgent endoscopy. Subject to country-specific variability, it is projected that with current mitigation measures in place, the peak incidence of active COVID-19 infections may be delayed by over 6 months. Although this aims to prevent the overburdening of healthcare systems, prolonged deferral of elective endoscopy will become unsustainable. Herein, we propose that by incorporating readily available point-of-care tests and conducting accurate clinical risk assessments, a safe and timely return to elective endoscopy is feasible. Our algorithm not only focuses on the safety of patients and healthcare workers, but also assists in rationalizing the use of invaluable resources such as personal protective equipment., (Copyright © 2020 American Society for Gastrointestinal Endoscopy. All rights reserved.)

Background & Aims: Endoscopist-directed propofol sedation (EDP) remains controversial. We sought to update the safety experience of EDP and estimate the cost of using anesthesia specialists for endoscopic sedation., Methods: We reviewed all published work using EDP. We contacted all endoscopists performing EDP for endoscopy that we were aware of to obtain their safety experience. These complications were available in all patients: endotracheal intubations, permanent neurologic injuries, and death., Results: A total of 646,080 (223,656 published and 422,424 unpublished) EDP cases were identified. Endotracheal intubations, permanent neurologic injuries, and deaths were 11, 0, and 4, respectively. Deaths occurred in 2 patients with pancreatic cancer, a severely handicapped patient with mental retardation, and a patient with severe cardiomyopathy. The overall number of cases requiring mask ventilation was 489 (0.1%) of 569,220 cases with data available. For sites specifying mask ventilation risk by procedure type, 185 (0.1%) of 185,245 patients and 20 (0.01%) of 142,863 patients required mask ventilation during their esophagogastroduodenoscopy or colonoscopy, respectively (P < .001). The estimated cost per life-year saved to substitute anesthesia specialists in these cases, assuming they would have prevented all deaths, was $5.3 million., Conclusions: EDP thus far has a lower mortality rate than that in published data on endoscopist-delivered benzodiazepines and opioids and a comparable rate to that in published data on general anesthesia by anesthesiologists. In the cases described here, use of anesthesia specialists to deliver propofol would have had high costs relative to any potential benefit.

Objective: The demand for endoscopic services is increasing rapidly. Of the several potential mechanisms to improve the supply of endoscopic procedures, improved efficiency in the endoscopy unit has received little attention., Methods: We invited 20 experienced endoscopists to participate in an initial evaluation of endoscopy efficiency, in which they were observed performing procedures in their own unit. Procedure volume per unit time was used as the measure of efficiency. Medical directors and head nurses at each endoscopy unit were interviewed regarding factors they perceived as most important in limiting procedure volume., Results: There was a greater than 3-fold variation in procedure volume score between the least efficient and most efficient endoscopists. The clearest trend predicting procedure volume score was short room turnover time (p = 0.0004). There was a trend toward improved procedure volume among endoscopists using another professional to sedate their patients and using two procedure rooms. The surveys of medical directors and head nurses suggested that multiple factors contribute to limiting procedure volume, but on average each perceived number of available doctors is the least important factor in limiting volume., Conclusions: Improving the efficiency of some endoscopists appears to be an important potential mechanism to meet the rising demand for endoscopic services. Increasing the resources that provide the opportunity for efficiency may be an important mechanism for increasing the availability of endoscopic services. Specific measures associated with improved efficiency include reduced room turnover times, and possibly use of two rooms per endoscopist and sedation by persons other than the endoscopist.

Objectives: Propofol has certain advantages over benzodiazepines plus narcotics as sedation for endoscopy. In a few centers, propofol has reportedly been used in endoscopic procedures and administered by nurses supervised by gastroenterologists without attendance by anesthesiologists or nurse anesthetists., Methods: As part of our continuous quality improvement program, we prospectively recorded the doses of propofol and adverse reactions to the drug in our initial 2000 cases. In all cases propofol was administered by nurses who were supervised by gastroenterologists, with no involvement by an anesthesia specialist., Results: The 2000 cases included 2222 procedures. There were five episodes of oxygen desaturation to <85%, four of which seemed to be related to excessive administration of propofol and were treated by brief (< 1 min) periods of mask ventilation. No patient required endotracheal intubation or hospital admission, or suffered long-term sequelae from propofol administration. There were no perforations in 977 colonoscopies., Conclusions: Propofol can be given safely by appropriately trained nurses under supervision by endoscopists. Technology that allows immediate detection of apnea would likely further improve its safety.

Accurate polyp size estimation during colonoscopy has an impact on clinical decision-making. A laser-based virtual scale endoscope (VSE) is available to allow measuring polyp size using a virtual adaptive scale. This study evaluates video-based polyp size measurement accuracy among expert endoscopists using either VSE or visual assessment (VA) with either snare as reference size or without any reference size information. A prospective, video-based study was conducted with 10 expert endoscopists. Video sequences from 90 polyps with known reference size (fresh specimen measured using calipers) were distributed on three different slide sets so that each slide set showed the same polyp only once with either VSE, VA or snare-based information. A slide set was randomly assigned to each endoscopist. Endoscopists were asked to provide size estimation based on video review. Relative accuracies for VSE, VA, and snare-based estimation were 75.1% (95% CI [71.6–78.5]), 65.0% (95% CI [59.5–70.4]) and 62.0% (95% CI [54.8–69.0]), respectively. VSE yielded significantly higher relative accuracy compared to VA (p = 0.002) and to snare (p = 0.001). A significantly lower percentage of polyps 1–5 mm were misclassified as >5 mm using VSE versus VA and snare (6.52% vs. 19.6% and 17.5%, p = 0.004) and a significantly lower percentage of polyps >5 mm were misclassified as 1–5 mm using VSE versus VA and snare (11.4% vs. 31.9% and 14.9%, p = 0.038). Endoscopists estimate polyp size with the highest accuracy when virtual adaptive scale information is displayed. Using a snare to assist sizing did not improve measurement accuracy compared to displaying visual information alone. [ABSTRACT FROM AUTHOR]

Many quality indicators have been proposed for colonoscopy, but most colonoscopists and endoscopy groups focus on measuring the adenoma detection rate and the cecal intubation rate. Use of proper screening and surveillance intervals is another accepted key indicator but it is seldom evaluated in clinical practice. Bowel preparation efficacy and polyp resection skills are areas that are emerging as potential key or priority indicators. This review summarizes and provides an update on key performance indicators for colonoscopy quality. [ABSTRACT FROM AUTHOR]

The article focuses on the approach of the author in dealing with anatomically difficult colons when conducting a colonoscopy. Topics include advantage of the approach is that it uses only standard instruments generally available in nearly all endoscopy units, experience of the author that standard length colonoscopies are easier to use, and use of barium enema and computed tomography colonography after an incomplete colonoscopy.

Background: Recent data indicate that the risk of cancer in colorectal lesions < 10 mm is lower than previously reported, possibly reflecting improved detection of flat, low-volume lesions with a low risk of cancer. Few studies have examined the prevalence of cancer in colorectal lesions 10 - 19 mm in size.Methods: We reviewed a prospectively collected database of all colorectal lesions removed at a single endoscopy center in order to identify lesions of 10 - 19 mm in size and review their histology. Lesions ≥ 20 mm were evaluated as a control group. We reviewed photographs of cancerous lesions to determine the frequency of endoscopic features of cancer.Results: A total of 5093 lesions ≥ 10 mm were removed from 4020 patients (mean age 63.2 years, 34.4 % female). Among 3068 lesions 10 - 19 mm in size, 28 (0.9 %) had adenocarcinoma, including 1.2 % of conventional adenomas and 0.3 % of serrated class lesions. These rates were lower than the 6.9 % and 2.0 % rates of cancer found in conventional adenomatous lesions and serrated lesions ≥ 20 mm, respectively. Cancer was suggested by endoscopic features in 52.0 % of malignancies 10 - 19 mm in size compared with 79.2 % of lesions ≥ 20 mm.Conclusions: The prevalence of cancer in 10 - 19 mm colorectal lesions was much lower than previously reported. The cancer risk was higher in conventional adenomas than in serrated lesions. Cancer was endoscopically evident prior to resection in slightly more than half of colorectal lesions 10 - 19 mm in size. [ABSTRACT FROM AUTHOR]

Background: Diminutive colorectal polyps resected during colonoscopy are sometimes histologically interpreted as normal tissue. The aim of this observational study was to explore whether errors in specimen handling or processing account in part for polyps ≤ 3 mm in size being interpreted as normal tissue by pathology when they were considered high confidence adenomas by an experienced endoscopist at colonoscopy.Methods: One endoscopist photographed 900 consecutive colorectal lesions that were ≤ 3 mm in size and considered endoscopically to be high confidence conventional adenomas. The photographs were reviewed blindly to eliminate poor quality images. The remaining 644 endoscopy images were reviewed by two external experts who predicted the histology while blinded to the pathology results.Results: Of 644 consecutive lesions ≤ 3 mm in size considered high confidence conventional adenomas by a single experienced colonoscopist, 15.4 % were reported as normal mucosa by pathology. The prevalence of reports of normal mucosa in polyps removed by cold snare and cold forceps were 15.2 % and 16.0 %, respectively. When endoscopy photographs were reviewed by two blinded outside experts, the lesions found pathologically to be adenomas and normal mucosa were interpreted as high confidence adenomas by endoscopic appearance in 96.9 % and 93.9 %, respectively, by Expert 1 (P = 0.15), and in 99.6 % and 100 %, respectively, by Expert 2 (P = 0.51).Conclusion: Retrieval and/or processing of tissue specimens of tiny colorectal polyps resulted in some lesions being diagnosed as normal tissue by pathology despite being considered endoscopically to be high confidence adenomas. These findings suggest that pathology interpretation is not a gold standard for lesion management when this phenomenon is observed. [ABSTRACT FROM AUTHOR]

The Multi-Society Task Force, in collaboration with invited experts, developed guidelines to assist health care providers with the appropriate provision of genetic testing and management of patients at risk for and affected with Lynch syndrome as follows: Figure 1 provides a colorectal cancer risk assessment tool to screen individuals in the office or endoscopy setting; Figure 2 illustrates a strategy for universal screening for Lynch syndrome by tumor testing of patients diagnosed with colorectal cancer; Figures 3,4,5,6 provide algorithms for genetic evaluation of affected and at-risk family members of pedigrees with Lynch syndrome; Table 10 provides guidelines for screening at-risk and affected persons with Lynch syndrome; and Table 12 lists the guidelines for the management of patients with Lynch syndrome. A detailed explanation of Lynch syndrome and the methodology utilized to derive these guidelines, as well as an explanation of, and supporting literature for, these guidelines are provided. [ABSTRACT FROM AUTHOR]

Background and study aims: A newer colonoscope series has optical magnification and improvement in image freezing function.We aimed to assess the impact on image capture, image quality, and polyp discrimination. Patients and methods: In consecutive patients undergoing outpatient colonoscopy images of colorectal polyps were taken with Olympus 190 or 180 series instruments. The number of image captures needed to obtain an adequate image, quality of stored images, proportion of polyps with a high confidence estimate of likely histology, and accuracy of interpretations were compared. Results: An acceptable image at the first attempt was obtained in 97.3% of photos with the 190 device vs. 83.8% with the 180 instrument (P<0.001). In the 190 group narrowband imaging (NBI) provided high confidence readings in 9% more cases than in the 180 group, but did not improve accuracy of polyp categorization. The quality of the stored images was judged better for the 190 device. However, when images that had provided high confidence estimates of polyp histology were re-interpreted later by the original endoscopist, there was agreement with the original interpretation for >98% of polyps in both the 180 group and the 190 group. A second endoscopist agreed with the original high confidence interpretations for 90% of polyps imaged with either the 180 or the 190 scope. Conclusion: The new colonoscope had less image blurring, improved subjective quality of stored images, and increased the proportion of high confidence endoscopic estimates of polyp histology, but did not improve accuracy in estimating polyp histology. [ABSTRACT FROM AUTHOR]

Abstract: Cold forceps are an appropriate tool for resection of 1-3-mm polyps that can be engulfed in a single bite. Jumbo and large-capacity forceps are more likely to engulf a tiny polyp in a single bite and are more effective and efficient than standard-size forceps. Cold snaring (transection of a polyp by guillotining without the use of electrocautery current) is more effective than either cold or hot forceps for resection of small polyps and can be used for polyps 1-9mm in size. The size at which hot snaring (the use of snare and cautery in the traditional manner for polypectomy) should be used is unknown, but the author often uses hot snaring for pedunculated polyps, bulky sessile polyps, and proximal colon serrated polyps that are 6-9mm in size. The cold snaring technique involves grasping a rim of normal tissue around the polyp and does not require tenting, and is therefore fundamentally different than hot snaring. Hot forceps should only be used for polyps ≤5mm in size, it can leave residual polyp and create a thermal injury that risks delayed hemorrhage and rarely perforation. The author never uses hot forceps. The current paradigm of diminutive polyp (polyps ≤5mm in size) management is to resect and send for pathologic evaluation. The pathology (adenoma vs hyperplastic) following removal is used to guide the postpolypectomy surveillance interval. Polyps in this size range very rarely have cancer, and infrequently have either villous elements or high-grade dysplasia. This observation has generated interest in developing endoscopic imaging technologies that could serve as alternatives to the pathologist''s examination of diminutive polyps and would be less expensive than the histologic evaluation. The American Society for Gastrointestinal Endoscopy has recommended minimum performance thresholds for imaging technologies with regard to 2 clinically relevant end points: (1) a policy of “resect and discard” for high-confidence interpretations of diminutive polyps anywhere in the colon and (2) leaving distal colon hyperplastic polyps in place without resection. Several technologies appear promising with regard to reaching the recommended performance thresholds, and additional study of how well they function when used by community endoscopists is awaited. [Copyright &y& Elsevier]

Objective Low-dose aspirin reduces colorectal cancer (CRC) incidence and mortality. Recently, the aspirin effect has been shown to occur primarily in the proximal colon. Colonoscopy has been either less effective or ineffective in the proximal compared to the distal colon. The authors assessed the cost-effectiveness of adding low-dose aspirin to a simulated screening with colonoscopy or sigmoidoscopy. Design A Markov model comparing the strategies of 10-year colonoscopy or sigmoidoscopy screening and the combination of either of the two with low-dose aspirin in 100 000 subjects aged 50 years until death was constructed. Proximal and distal CRC prevention rates with endoscopy or aspirin were extracted from the literature. Screening and aspirin prevention were simulated to stop at 80 years. The cost of aspirin and aspirin-related complications, as well as aspirin-related mortality, was included. Incremental cost-effectiveness ratios between the different strategies were calculated. Sensitivity and probabilistic analyses were also performed. Results The addition of low-dose aspirin to colonoscopy and sigmoidoscopy screening increased the CRC death prevention rate from 68% and 39% to 81% and 69%, respectively. Lifetime aspirin-related mortality appeared to be 0.1%. Because of the substantial reduction in CRC care, the addition of aspirin to colonoscopy and sigmoidoscopy screening was cost-effective (incremental cost-effectiveness ratio: US$5413 per life-year saved) and cost saving (US$278 per person), respectively. When the proximal CRC prevention rate with colonoscopy was increased 56% to 73% from the baseline, the addition of aspirin was no longer cost-effective. The addition of aspirin to colonoscopy and sigmoidoscopy was a cost-effective strategy in 52% and 94% of the scenarios at probabilistic analysis. Conclusions When assuming a suboptimal efficacy of endoscopy in preventing CRC, the addition of low-dose aspirin may be an effective and cost-effective strategy, mainly because of its high efficacy in preventing proximal CRC. [ABSTRACT FROM AUTHOR]

Background & Aims: Colonoscopy may have a greater protective effect for distal colorectal cancer (CRC) than proximal CRC. Serrated polyps are frequently located in the proximal colon, can be missed during colonoscopy, and may progress to CRC. We investigated the prevalence and endoscopist detection rates of proximal serrated polyps in a large cohort of average risk patients undergoing screening colonoscopy. Methods: Screening colonoscopies performed by 15 attending gastroenterologists at 2 academic endoscopy units between 2000 and 2009 were reviewed. Serrated polyps included hyperplastic polyps, sessile serrated adenomas, and traditional serrated adenomas. Endoscopist-level detection rates for adenomas and serrated polyps were calculated. Pearson correlation coefficients were calculated to evaluate the associations of adenoma and proximal serrated polyp detection rates. Logistic regression was used to compare endoscopists’ detection rates. Results: A total of 11,049 polyps were detected in 6681 colonoscopies (adenomas: 5637, 51%; serrated: 3984, 36%; proximal serrated: 1238, 11%). The proportion of colonoscopies with at least one proximal serrated polyp was 13% (range 1%–18%). Proximal serrated polyp detection rates per colonoscopy ranged from 0.01 to 0.26. Adenoma and proximal serrated polyp detection rates per colonoscopy were strongly correlated (R = 0.76, P = .0005). The odds of detecting at least one proximal serrated polyp for individual endoscopists ranged from 0.05 to 0.67 compared to the highest level detector. Endoscopist (P < .0001), but not patient age (P = .76) or gender (P = .95), was associated with proximal serrated polyp detection. Conclusions: In an average-risk screening cohort, the detection of proximal serrated polyps was highly variable and endoscopist dependent. A significant proportion of proximal serrated polyps may be missed during colonoscopy. High-quality colonoscopy is important for the detection and resection of all polyps with neoplastic potential. [Copyright &y& Elsevier]

The article presents a statement on the use of nonanesthesiologist-administered propofol (NAAP) gastrointestinal (GI) endoscopy, issued jointly by the American Association for the Study of Liver Diseases, American College of Gastroenterology, and American Gastroenterological Association. According to this statement, the administration of propofol and standard sedation by nonanesthesiologists is comparable with respect to their efficacy and safety profiles. Further details are offered.

This is a review of basic principles applicable to the use of propofol by trained endoscopists and nurses for endoscopy, without the involvement of an anesthesia specialist (an anesthesiologist or certified registered nurse anesthetist). The review also explicitly describes the nature of the current controversy surrounding the use of propofol by endoscopists, implies its origins in financial incentives, and outlines obstacles to the use of endoscopist-directed propofol. [Copyright &y& Elsevier]

Background & Aims: The ability to determine colorectal polyp pathology by endoscopy could reduce the risks of polypectomy and the cost of pathologic evaluation. This study evaluated the ability of the Olympus Exera 180 high-definition colonoscope (Olympus America, Inc, Center Valley, PA), with narrow-band imaging, to predict colorectal polyp histology. Methods: A library of 320 endoscopic photographs with correlated histologic information was used to identify endoscopic features associated with adenomatous and hyperplastic histology. These features were tested in a prospective study of 451 consecutively identified colorectal polyps. Polyps were observed endoscopically and assigned a designation of high or low confidence. The primary end points were the predictive value of high-confidence endoscopic interpretations of adenoma and hyperplastic histology for polyps 5 mm and smaller in size. Results: Endoscopic predictions of adenoma and hyperplastic histology were made with high confidence for 80% and 83% of cases, respectively. High-confidence predictions were more likely than low-confidence predictions to be correct (P < .001). High-confidence predictions of adenoma and hyperplastic histology were correct for 91% and 95%, respectively, of polyps 5 mm and smaller in size. Conclusions: Introduction of confidence levels to the endoscopic interpretation of colorectal polyp histology allows sufficient accuracy for the use of the Exera narrow-band imaging system in the identification of distal hyperplastic polyps that do not need resection, as well as to plan postpolypectomy surveillance without pathologic evaluation of polyps 5 mm in size or smaller. [Copyright &y& Elsevier]

Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stages II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double-contrast barium enema or computed tomography colonography should be performed preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that examination is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see “Guidelines for Colonoscopy Surveillance After Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society”). Shorter intervals also are indicated if the patient’s age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer. [Copyright &y& Elsevier]

The article reports on the guidelines which were updated by the American Cancer Society and the US Multi-Society Task Force on Colorectal Cancer regarding the use of endoscopy in colorectal cancer surveillance and resection. It presents steps and recommendations for clinicians that will aid them in clearing synchronous diseases and colonoscopy.

BACKGROUND: Loop formation during colonoscopy insertion results in patient pain and delays in advancement of the colonoscope tip.AIM: To assess the insertability and safety of a novel shape-locking guide (ShapeLock, USGI, San Clemente, CA) that resists looping during colonoscopy.RESULTS: In 54 patients, both a disposable and a partly reusable version of the ShapeLock received high scores (mean scores>9.0 on 1–10 scale) for ease of insertion, and ability to maneuver the colonoscope through the shape locked device. No significant trauma resulted from use of the device.CONCLUSION: A novel shape-locking device for colonoscopy can be readily and safely inserted into the colon and locked. The device warrants controlled evaluation to determine in which, if any cases, it may be useful for either experienced colonoscopists and/or those with less or minimal experience.(Am J Gastroenterol 2005;100:1-4) [ABSTRACT FROM AUTHOR]

Propofol use for endoscopy is increasing rapidly. Its administration by registered nurses under the supervision of endoscopists has thus far proven safe, but is not realistically feasible in most U.S. endoscopy units. Therefore, propofol in the United States is being administered almost entirely by anesthetists. Transition to anesthetist-delivered sedation for endoscopy is being accompanied by increased costs, which in turn has the potential to adversely affect endoscopic practice. The gastroenterology and anesthesia communities should work together to explore mechanisms to expand propofol use or an alternative for endoscopy in a safe and cost-effective manner. Propofol use for endoscopy is increasing rapidly. Its administration by registered nurses under the supervision of endoscopists has thus far proven safe, but is not realistically feasible in most U.S. endoscopy units. Therefore, propofol in the United States is being administered almost entirely by anesthetists. Transition to anesthetist-delivered sedation for endoscopy is being accompanied by increased costs, which in turn has the potential to adversely affect endoscopic practice. The gastroenterology and anesthesia communities should work together to explore mechanisms to expand propofol use or an alternative for endoscopy in a safe and cost-effective manner. [ABSTRACT FROM AUTHOR]

BACKGROUND: Small polyps are routinely missed during colonoscopy even with careful examination. AIM: To determine and compare endoscopic efficiency and polyp miss rate between a prototype 1700 wide-angle (WA) colonoscope and a standard (S) colonoscope. METHODS: Two consecutive same-day colonoscopies were performed in 50 patients with intact colons. The patients were randomized to undergo the first colonoscopy with either the prototype WA 170° angle of view colonoscope or an S adult 140° angle of view colonoscope. RESULTS: The mean time for insertion was 2.09 (1.09) mm versus 2.53 (1.47) mm (p = 0.002) for the WA colonoscope and the S colonoscope, respectively. Similarly, the mean time for examination during withdrawal was shorter with the WA colonoscope (4.98 (0.94) vs 5.74 (1.12) mm; p <0.0001). The mean insertion time for the second examination was shorter than the insertion time for the first examination, irrespective of the colonoscope (p = 0.006). However, the withdrawal times were not significantly different between the first and second examinations (p = 0.11). The miss rate for all polyps with the WA colonoscope (19%) was similar to the miss rate with the S colonoscope (27%; p = 0.19). The miss rates for adenomas with the WA (10/33; 30.3%) and the S scope (15/50; 30%) were similar (p = 0.98). CONCLUSIONS: The use of the WA colonoscope was associated with a reduction in insertion time to the cecum, as well as examination time during withdrawal. No evidence was found that the accuracy of the two colonoscopes differs. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Nurse-administered propofol has gained attention as a safe and effective means of sedation for patients undergoing endoscopic procedures. However, little is known about the effect of propofol on the technical performance of colonoscopy.METHODS: Three separate studies were conducted. In the first study, we reviewed procedure notes from consecutive colonoscopies performed by a single experienced endoscopist at our hospital endoscopy unit on patients sedated with either nurse-administered propofol (n= 162) or midazolam/narcotic (n= 164). In the second study, 100 eligible colonoscopy outpatients were randomized to receive either nurse-administered propofol (n= 50) or midazolam/fentanyl (n= 50). In both studies, the measured parameters included visualization of the cecum, time required to reach the cecum, repositioning of the patient, and the application of abdominal counterpressure. In a third study, we reviewed the rate of cecal intubation and colonic perforation in the first 2357 patients in our unit receiving nurse-administered propofol.RESULTS: In the retrospective comparative study, there was no difference in the cecal intubation rate in those receiving propofol (99.4%) compared to those receiving midazolam/narcotic (97%;p= 0.1), and three of five failed cecal intubations in the latter group resulted from obstructing masses. Patients sedated with propofol were repositioned less frequently compared to those receiving midazolam/narcotic (3.7%vs26.2%) (p<0.0001). Abdominal pressure was employed in 9.9% of patients sedated with propofol compared to 19.5% (p= 0.01) of those given midazolam/narcotic. The mean time to reach the cecum was lower in the propofol group than in the midazolam/narcotic group (4.6 minvs6.0 min,p= 0.002). In the prospective randomized study, the endoscopist intubated the cecum in all 100 patients. Patients in the propofol group were repositioned less frequently than those in the midazolam/fentanyl group (2%vs24%, respectively,p= 0.001). The number of cases requiring abdominal counterpressure was not significantly different between the propofol and midazolam/fentanyl groups (12%vs24%, respectively,p= 0.1). The mean time to reach the cecum in the propofol group (3.2 min) was similar to that in the midazolam/fentanyl group (3.8 min,p= 0.08). Among the first 2357 patients in our unit undergoing colonoscopy with nurse-administered propofol, the rate of complete colonoscopy was 99.2% and there were no perforations.CONCLUSION: Nurse-administered propofol sedation is safe and simplifies the technical performance of colonoscopy compared to midazolam/narcotic sedation. [ABSTRACT FROM AUTHOR]

: ObjectiveNarcotics and benzodiazepines are commonly used for sedation for endoscopy in the United States. Propofol has certain advantages over narcotics and benzodiazepines, but its use is often controlled by anesthesia specialists. This report describes our experience with dosage, safety, patient satisfaction, and discharge time with nurse-administered propofol sedation in 9152 endoscopic cases.: MethodsThe study was performed in a private practice ambulatory surgery center in Medford, Oregon. With the assistance of an anesthesiologist, we developed a protocol for administration of propofol in routine endoscopic cases, in which propofol was given by registered nurses under the supervision of endoscopists or gastroenterologists. We then applied the protocol with 9152 patients.: ResultsThere were seven cases of respiratory compromise (three prolonged apnea, three laryngospasm, one aspiration requiring hospitalization), all associated with upper endoscopy. Five patients required mask ventilation, but none required endotracheal intubation. There were seven colonic perforations (<1 per 1000 colonoscopies), of which three may have involved forceful sigmoid disruption. Of patients who had previously received narcotic or benzodiazepine sedation, 84% preferred propofol. Gastroenterologists strongly preferred propofol. The mean time from completion of procedures to discharge in a sample of 100 patients was 18 min.: ConclusionNurse-administered propofol sedation in an ambulatory surgery center was safe and resulted in high levels of patient satisfaction and rapid postprocedure recovery and discharge. [Copyright &y& Elsevier]

: ObjectiveAccessing the proximal sides of colorectal folds, flexures, and valves can be difficult endoscopically and can contribute to missed lesions and failed therapeutic procedures. The aim of this study was to determine whether a prototype colonoscope with a short bending section could facilitate accessing difficult to reach areas proximal to folds, flexures, and valves.: MethodsIn a nonrandomized study, the prototype colonoscope, a standard pediatric colonoscope, and a standard adult colonoscope were used to attempt retroflexion in the cecum and, if unsuccessful, in the right colon.: ResultsThe prototype colonoscope allowed cecal retroflexion, including clear visualization of the ileocecal valve and the cecal mucosa medial to the valve, in 95% of attempts. A standard pediatric colonoscope was successful in 50% and a standard adult colonoscope in 24.5%. The prototype was more successful than both the standard pediatric (p < 0.001) and the standard adult instrument (p < 0.001). The standard pediatric colonoscope was successful more often than the standard adult colonoscope (p = 0.02).: ConclusionUsing the ability to retroflex in the cecum as a surrogate marker, a prototype pediatric colonoscope with a short bending section seems to facilitate retroflexion and visualization of the proximal aspects of difficult to see regions in the proximal colon. [Copyright &y& Elsevier]

: BackgroundWireless capsule endoscopy (WCE) is a new technology for small bowel imaging.: AimTo report our initial experience with sensitivity of high quality enteroclysis in patients with small bowel ulcers detected by WCE.: MethodsMedical records of all patients referred for WCE from December, 2001 to April, 2002 at our institution were reviewed. All patients had negative upper and lower endoscopies and small bowel barium studies before WCE.: ResultsThere were 40 patients (19 female, mean age 57.3 yr) during this study period. Three patients had multiple small bowel ulcers detected by WCE. One with ileal ulcers and abdominal pain had an enteroclysis at another hospital before WCE. Review of the study at our institution showed that it was of excellent quality and was normal. Two patients with chronic iron deficiency anemia had multiple small bowel ulcers and were referred after WCE for a repeat small bowel barium study by biphasic enteroclysis performed by experienced GI radiologists. The radiologists were told in advance of the WCE findings. Both studies were considered technically to be of perfect quality. Despite this, both studies were negative. All 3 patients improved after therapy for Crohn’s disease.: ConclusionsOur data indicates that WCE may be more sensitive for small bowel ulcers than the best enteroclysis available. [Copyright &y& Elsevier]

OBJECTIVE:Recent studies have identified a group of polyps, usually located in the proximal colon, with distinct endoscopic features that predict hyperplastic histology. These polyps may occasionally have foci of dysplastic (adenomatous) tissue. We aimed to define the prevalence of adenomatous foci in these polyps.METHODS:Fifty-one consecutive hyperplastic-appearing proximal colon polyps were sectioned at 1-mm intervals for histological analysis.RESULTS:All 51 polyps were hyperplastic, but two (4%) had foci of adenomatous tissue.CONCLUSION:The prevalence of adenomatous foci in proximal colon polyps with endoscopic features of hyperplastic polyps is low. Whether endoscopic resection of polyps with these features is warranted remains uncertain. [Copyright &y& Elsevier]

Objective: The prevalence of colonic angiodysplasia (AD) among healthy asymptomatic people is unknown, and the natural history of these lesions has not been clearly defined. The purpose of our study was to determine prevalence and to review and assess the natural history of AD. Methods: Each of the authors had previously published his own prospective study that involved screening colonoscopy for the detection of neoplasia in asymptomatic adult men and women who had never bled. Ail pathological lesions diagnosed by endoscopy were recorded, but only data pertaining to polyps were published. We pooled and analyzed the endoscopic findings (raw data) from those studies and assessed the natural history of the lesions by reviewing the medical charts of affected subjects to determine whether bleeding had occurred. Nine hundred sixty-four patients were evaluated (mean age, 62 yr). All were ≥ 50 yr old (range, 50-79 yr), not anemic, Hemoccult negative, asymptomatic, and had full colonoscopy to the cecum. Results: Eight subjects had AD (prevalence, 0.83%). Lesions in affected individuals were usually small (mean size, 4.0 mm) and most often were located in the right colon (62%). No subject bled, and all maintained a stable hemoglobin (mean, 14.6 g%) with a mean follow-up of 3 yr. Conclusions: We conclude that 1) colonic AD is uncommon among healthy asymptomatic people (prevalence, 0.83%), 2) lesions are usually small (<10 mm) and are located proximal to the hepatic flexure, 3) the natural history for AD in these people is benign, and the risk of bleeding over a 3-yr period is low (0% in 3 yr), and 4) because of this low risk, endoscopic treatment for incidental (nonbleeding) AD is unnecessary. [ABSTRACT FROM AUTHOR]

Background & Aims: The prevalence of synchronous neoplasia in patients with large sessile colorectal adenomas is uncertain. Methods: We conducted a retrospective single-center review of synchronous neoplastic findings in 190 consecutive patients with intact colons and single large sessile adenomas resected endoscopically. Synchronous polyps were those removed at the colonoscopy that discovered the large sessile adenoma or at any follow-up endoscopic examination within 12 months of discovery of the large sessile adenoma. Results: Seventy-five percent of patients had at least 1 synchronous adenoma, and the 190 patients had a mean of 4 synchronous adenomas. Thirty percent of patients had ≥1 synchronous advanced adenoma (adenoma ≥1 cm in size or with high-grade dysplasia or villous elements). There were a total of 116 synchronous advanced adenomas, including 89 adenomas 10–19 mm in size and 8 that were ≥20 mm in size. Conclusions: Colonoscopists should be aware that patients with large sessile adenomas have a high prevalence of synchronous advanced neoplasia. Prospective study of this issue is warranted. [Copyright &y& Elsevier]

The author reflects on the dominance of colonoscopy in the diagnosis and surveillance imaging in the colon and colorectal cancer screening in the medical sector in the U.S. There are several reasons for colonoscopy's popularity; first, colonoscopy is widely and accurately perceived as the most sensitive method to detect adenomas, second, it is multifunctional, which means can be used for diagnosis and therapeutics in a single session.

In 2002, the U.S. MultiSociety Task Force on Colorectal Cancer proposed multiple quality indicators for use in the continuous quality improvement (CQI) process for colonoscopy. The quality indicators were not prioritized for implementation in clinical practice. This editorial reviews evidence suggesting that after cecal intubation rates, two quality indicators should be the priorities for the CQI process for colonoscopy: (1) measurement of individual endoscopists' adenoma detection rates and (2) recommended intervals for postpolypectomy surveillance colonoscopy. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Given Imaging (Yoqneam, Israel) has developed a suspected blood indicator (SBI) function for its wireless capsule endoscopy (WCE) software. The SBI detects blood and marks appropriate images for interrogation. The sensitivity and accuracy of SBI and its role in examining WCE studies is unknown. Our aim was to evaluate the accuracy of this new software in detecting small bowel lesions. METHODS: WCE reports of all patients referred for WCE in October and November, 2002, were reviewed. The images from each patient were reviewed by experienced gastroenterologists at 15 frames/s. The findings detected by gastroenterologists were compared to those recognized by SBI. Arteriovenous malformations (AVMs), ulcers, erosions, and sites of active bleeding were considered significant lesions. RESULTS: A total of 24 patients (16 women and eight men, mean age 59 yr) were studied during this period. The indications for the study were iron deficiency anemia in 18 patients and abdominal pain in six patients. A total of 109 lesions were identified by gastroenterologists (47 AVMs, 18 active bleeding ulcers, 18 ulcers without bleeding, and 26 erosions). Active bleeding seen by gastroenterologists was secondary to AVMs (five cases), jejunal ulcers (11 cases, all in the same patient), and gastric ulcers (two cases). A total of 31 potential areas of blood were identified by SBI. When compared to those findings recognized by gastroenterologists, 28 lesions were correctly identified (six AVMs, 13 active bleeding ulcers, (three AVMs and 10 jejunal ulcers), seven nonbleeding ulcers, and two nonbleeding erosions. The overall sensitivity, positive predictive value, and accuracy of SBI to detect significant small bowel lesions were 25.7%, 90%, and 34.8%, respectively. If only actively bleeding lesions in the small bowel were considered, SBI had sensitivity, positive predictive value, and accuracy of 81.2%, 81.3%, and 83.3%, respectively. CONCLUSIONS: SBI has good sensitivity and positive predictive value for actively bleeding lesions in the small bowel. Complete review of the study by the physician is still needed. SBI should be considered as a complementary and rapid screening tool for gastroenterologists to identify actively bleeding lesions. [ABSTRACT FROM AUTHOR]

Interval cancers occur more frequently in the right colon. One reason could be that right-sided adenomas are frequently missed in colonoscopy examinations. We reanalyzed data from tandem colonoscopies to assess adenoma miss rates in relation to location and other factors. We pooled data from 8 randomized tandem trials comprising 2218 patients who had diagnostic or screening colonoscopies (adenomas detected in 49.8% of patients). We performed a mixed-effects logistic regression with patients as cluster effects with different independent parameters. Factors analyzed included location (left vs right, splenic flexure as cutoff), adenoma size, form, and histologic features. Analyses were controlled for potential confounding factors such as patient sex and age, colonoscopy indication, and bowel cleanliness. Right-side location was not an independent risk factor for missed adenomas (odds ratio [OR] compared with the left side, 0.94; 95% CI, 0.75–1.17). However, compared with adenomas ≤5 mm, the OR for missing adenomas of 6–9 mm was 0.62 (95% CI, 0.44–0.87), and the OR for missing adenomas of ≥10 mm was 0.51 (95% CI, 0.33–0.77). Compared with pedunculated adenomas, sessile (OR, 1.82; 95% CI, 1.16–2.85) and flat adenomas (OR, 2.47; 95% CI, 1.49–4.10) were more likely to be missed. Histologic features were not significant risk factors for missed adenomas (OR for adenomas with high-grade intraepithelial neoplasia, 0.68; 95% CI, 0.34–1.37 and OR for sessile serrated adenomas, 0.87; 95% CI, 0.47–1.64 compared with low-grade adenomas). Men had a higher number of adenomas per colonoscopy (1.27; 95% CI, 1.21–1.33) than women (0.86; 95% CI, 0.80–0.93). Men were less likely to have missed adenomas than women (OR for missed adenomas in men, 0.73; 95% CI, 0.57–0.94). In an analysis of data from 8 randomized trials, we found that right-side location of an adenoma does not increase its odds for being missed during colonoscopy but that adenoma size and histologic features do increase risk. Further studies are needed to determine why adenomas are more frequently missed during colonoscopies in women than men. [ABSTRACT FROM AUTHOR]

Background & Aims: Almost all colorectal polyps ≤5 mm are benign, yet current practice requires costly pathologic analysis. We aimed to develop and evaluate the validity of a simple narrow-band imaging (NBI)-based classification system for differentiating hyperplastic from adenomatous polyps. Methods: The study was conducted in 4 phases: (1) evaluation of accuracy and reliability of histologic prediction by NBI-experienced colonoscopists; (2) development of a classification based on color, vessels, and surface pattern criteria, using a modified Delphi method; (3) validation of the component criteria by people not experienced in endoscopy or NBI analysis (25 medical students, 19 gastroenterology fellows) using 118 high-definition colorectal polyp images of known histology; and (4) validation of the classification system by NBI-trained gastroenterology fellows, using still images. We performed a pilot evaluation during real-time colonoscopy. Results: We developed a classification system for the endoscopic diagnosis of colorectal polyp histology and established its predictive validity. When all 3 criteria were used, the specificity ranged from 94.9% to 100% and the combined sensitivity ranged from 8.5% to 61.0%. The specificities of the individual criteria were lower although the sensitivities were higher. During real-time colonoscopy, endoscopists made diagnoses with high confidence for 75% of consecutive small colorectal polyps, with 89% accuracy, 98% sensitivity, and 95% negative predictive values. Conclusions: We developed and established the validity of an NBI classification system that can be used to diagnose colorectal polyps. In preliminary real-time evaluation, the system allowed endoscopic diagnoses of colorectal polyp histology. [ABSTRACT FROM AUTHOR]

An abstract of the article "Propofol versus midazolam/fentanyl for outpatient colonoscopy: Administration by nurses supervised by endoscopists," by Brian J Ulmer and colleagues is presented.

The article discusses the U.S. Multi-Society Task Force on Colorectal Cancer (CRC) recommendations on the endoscopic recognition and management strategies for malignant colorectal polyps. Also cited are a guideline on the assessment of lesions linked to cancer, endoscopic management, and how to determine whether a surgery is required if a malignant polyp was endoscopically resected.

Background & Aims: Respiratory complications represent an important adverse event of endoscopic procedures. We screened for respiratory complications after endoscopic procedures using a questionnaire and followed-up patients suggestive of respiratory infection. Method: In this prospective observational, multicenter study performed in Outpatient practices of gastroenterology we investigated 15,690 patients by questionnaires administered 24 hours after the endoscopic procedure. Results: 832 of the 15,690 patients stated at least one respiratory symptom after the endoscopic procedure: 829 patients reported coughing (5.28%), 23 fever (0.15%) and 116 shortness of breath (SOB, 0.74%); 130 of the 832 patients showed at least two concomitant respiratory symptoms (107 coughing + SOB, 17 coughing + fever, 6 coughing + coexisting fever + SOB) and 126 patients were followed-up to assess their respiratory complaints. Twenty-nine patients (follow-up: 22.31%, whole sample: 0.18%) reported signs of clinically evident respiratory infection and 15 patients (follow-up: 11.54%; whole sample: 0.1%) received therefore antibiotic treatment. Coughing or vomiting during the endoscopic procedure resulted in a 156.12-fold increased risk of respiratory complications (95% Cl: 67.44 - 361.40) and 520.87-fold increased risk of requiring antibiotic treatment (95% Cl: 178.01 - 1524.05). All patients of the follow-up sample who coughed or vomited during endoscopy developed clinically evident signs of respiratory infection and required antibiotic treatment while this occurred in a significantly lower proportion of patients without these symptoms (17.1% and 5.1%, respectively). Conclusions: We demonstrated that respiratory complications following endoscopic sedation are of comparably high incidence and we identified major predictors of aspiration pneumonia which could influence future surveillance strategies after endoscopic procedures. [ABSTRACT FROM AUTHOR]

Summary: Background: Although colonoscopy is the accepted standard for detection of colorectal adenomas and cancers, many adenomas and some cancers are missed. To avoid interval colorectal cancer, the adenoma miss rate of colonoscopy needs to be reduced by improvement of colonoscopy technique and imaging capability. We aimed to compare the adenoma miss rates of full-spectrum endoscopy colonoscopy with those of standard forward-viewing colonoscopy. Methods: We did an international, multicentre, randomised trial at three sites in Israel, one site in the Netherlands, and two sites in the USA between Feb 1, 2012, and March 31, 2013. Patients aged 18–70 years referred for colorectal cancer screening, polyp surveillance, or diagnostic assessment underwent same-day, back-to-back tandem colonoscopy with standard forward-viewing colonoscope and the full-spectrum endoscopy colonoscope. The patients were randomly assigned (1:1), via computer-generated randomisation with block size of 20, to which procedure was done first. The endoscopist was masked to group allocation until immediately before the start of colonoscopy examinations; patients were not masked. The primary endpoint was adenoma miss rates. We did per-protocol analyses. This trial is registered with ClinicalTrials.gov, number NCT01549535. Findings: 197 participants were enrolled. 185 participants were included in the per-protocol analyses: 88 (48%) were randomly assigned to receive standard forward-viewing colonoscopy first, and 97 (52%) to receive full-spectrum endoscopy colonoscopy first. By per-lesion analysis, the adenoma miss rate was significantly lower in patients in the full-spectrum endoscopy group than in those in the standard forward-viewing procedure group: five (7%) of 67 vs 20 (41%) of 49 adenomas were missed (p<0·0001). Standard forward-viewing colonoscopy missed 20 adenomas in 15 patients; of those, three (15%) were advanced adenomas. Full-spectrum endoscopy missed five adenomas in five patients in whom an adenoma had already been detected with first-pass standard forward-viewing colonoscopy; none of these missed adenomas were advanced. One patient was admitted to hospital for colitis detected at colonoscopy, whereas five minor adverse events were reported including vomiting, diarrhoea, cystitis, gastroenteritis, and bleeding. Interpretation: Full-spectrum endoscopy represents a technology advancement for colonoscopy and could improve the efficacy of colorectal cancer screening and surveillance. Funding: EndoChoice. [ABSTRACT FROM AUTHOR]