One-fourth of colorectal neoplasias are missed during screening colonoscopies; these can develop into colorectal cancer (CRC). Deep learning systems allow for real-time computer-aided detection ...(CADe) of polyps with high accuracy. We performed a multicenter, randomized trial to assess the safety and efficacy of a CADe system in detection of colorectal neoplasias during real-time colonoscopy.
We analyzed data from 685 subjects (61.32 ± 10.2 years old; 337 men) undergoing screening colonoscopies for CRC, post-polypectomy surveillance, or workup due to positive results from a fecal immunochemical test or signs or symptoms of CRC, at 3 centers in Italy from September through November 2019. Patients were randomly assigned (1:1) to groups who underwent high-definition colonoscopies with the CADe system or without (controls). The CADe system included an artificial intelligence–based medical device (GI-Genius, Medtronic) trained to process colonoscopy images and superimpose them, in real time, on the endoscopy display a green box over suspected lesions. A minimum withdrawal time of 6 minutes was required. Lesions were collected and histopathology findings were used as the reference standard. The primary outcome was adenoma detection rate (ADR, the percentage of patients with at least 1 histologically proven adenoma or carcinoma). Secondary outcomes were adenomas detected per colonoscopy, non-neoplastic resection rate, and withdrawal time.
The ADR was significantly higher in the CADe group (54.8%) than in the control group (40.4%) (relative risk RR, 1.30; 95% confidence interval CI, 1.14–1.45). Adenomas detected per colonoscopy were significantly higher in the CADe group (mean, 1.07 ±1.54) than in the control group (mean 0.71 ± 1.20) (incidence rate ratio, 1.46; 95% CI, 1.15–1.86). Adenomas 5 mm or smaller were detected in a significantly higher proportion of subjects in the CADe group (33.7%) than in the control group (26.5%; RR, 1.26; 95% CI, 1.01–1.52), as were adenomas of 6 to 9 mm (detected in 10.6% of subjects in the CADe group vs 5.8% in the control group; RR, 1.78; 95% CI, 1.09–2.86), regardless of morphology or location. There was no significant difference between groups in withdrawal time (417 ± 101 seconds for the CADe group vs 435 ± 149 for controls; P = .1) or proportion of subjects with resection of non-neoplastic lesions (26.0% in the CADe group vs 28.7% of controls; RR, 1.00; 95% CI, 0.90–1.12).
In a multicenter, randomized trial, we found that including CADe in real-time colonoscopy significantly increases ADR and adenomas detected per colonoscopy without increasing withdrawal time. ClinicalTrials.gov no: 04079478
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False positive (FP) results by computer-aided detection (CADe) hamper the efficiency of colonoscopy by extending examination time. Our aim was to develop a classification of the causes and clinical ...relevance of CADe FPs, and to assess the relative distribution of FPs in a real-life setting.
In a post-hoc analysis of a randomized trial comparing colonoscopy with and without CADe (NCT: 04079478), we extracted 40 CADe colonoscopy videos. Using a modified Delphi process, 4 expert endoscopists identified the main domains for the reasons and clinical relevance of FPs. Then, 2 expert endoscopists manually examined each FP and classified it according to the proposed domains. The analysis was limited to the withdrawal phase.
The 2 main domains for the causes of CADe FPs were identified as artifacts due to either the mucosal wall or bowel content, and clinical relevance was defined as the time spent on FPs and the FP rate per minute. The mean number of FPs per colonoscopy was 27.3 ± 13.1, of which 24 ± 12 (88%) and 3.2 ± 2.6 (12%) were due to artifacts in the bowel wall and bowel content, respectively. Of the 27.3 FPs per colonoscopy, 1.6 (5.7%) required additional exploration time of 4.8 ± 6.2 seconds per FP (ie, 0.7% of the mean withdrawal time). In detail, 15 (24.2%), 33 (53.2%), and 14 (22.6%) FPs were classified as being of mild, moderate, or severe clinical relevance. The rate of FPs per minute of withdrawal time was 2.4 ± 1.2, and was higher for FPs due to artifacts from the bowel wall than for those from bowel content (2.4 ± 0.6 vs 0.3 ± 0.2, P < .001).
FPs by CADe are primarily due to artifacts from the bowel wall. Despite a high frequency, FPs result in a negligible 1% increase in the total withdrawal time because most of them are immediately discarded by the endoscopist.
Multiple therapeutic modalities including surgery and rigid and flexible endoscopy have been adopted to manage Zenker's diverticulum (ZD). Minimally invasive flexible endoscopic septotomy (FES) ...techniques have been increasingly favored over the past 20 years; however, long-term data are still scanty. The aim of this study is to evaluate early and long-term outcomes of FES for naive ZD in a single-center setting.
From 2010 to 2017, ZD patients treated with FES were included in a prospectively maintained database (NCT03948438). Those who had already been treated surgically or endoscopically were excluded from the analysis. The Dakkak and Bennett dysphagia scale was used to rate the dysphagia. Persistent complete or near-complete resolution of symptoms (Dakkak and Bennett 0 or 1) was defined as clinical success. Postprocedural adverse events were reported according to ASGE lexicon.
Overall, 256 consecutive patients were treated. Mean pouch size was 29.8 ± 11.3 mm. The procedure was successfully completed in all scheduled patients, with an early clinical success of 96.1%. Adverse events occurred in 3.5% (9/256) of patients. Eight of them were mild/moderate with no fatal events, whereas one patient required surgery. Recurrences occurred in 31.3% (80/256) of treated patients after a mean time of 9 ± 3 months and 95% of recurrences were treated by a second FES. At an average follow-up of 5.5 years, 95.3% of patients were asymptomatic after a mean number of 1.3 procedures.
FES is a safe and effective treatment modality for patients with ZD. Recurrence rate is significant; however, endoscopic reintervention is associated with long-term relief of dysphagia.
Background:
The endoscopic submucosal dissection (ESD) is a technically demanding and time-consuming procedure, with an increased risk of adverse events compared to standard endoscopic resection ...techniques. The main difficulties are related to the instability of the operating field and to the loss of traction. We aimed to evaluate in a pilot trial a new endoscopic platform tissue retractor system (TRS); ORISE, Boston scientific Co., Marlborough, MA, USA, designed to stabilize the intraluminal space, and to provide tissue retraction and counter traction.
Method:
We prospectively enrolled all consecutive patients who underwent an ESD for sigmoid/rectal lesions. The primary outcome was the rate of technical feasibility. Further technical aspects such as en-bloc and R0 resection rate, number of graspers used, circumferential incision time, TRS assemblage time, submucosal dissection time, and submucosal dissection speed were provided. Clinical outcomes (recurrence rate and adverse events) were recorded as well.
Results:
In all, 10 patients (M/F 4/6, age: 70.4 ± 11.0 years old) were enrolled. Eight out of 10 lesions were located in the rectum. Average lesion size was 31.2 ± 2.7 mm, and mean lesion area was 1628.88 ± 205.3 mm2. The two sigmoid lesions were removed through standard ESD, because the platform assemblage failed after several attempts. All rectal lesions were removed in an en-bloc fashion. R0 resection was achieved in 7/8 (87.5%) patients in an average procedure time of 60.5 ± 23.3 min. None of the patients developed neither intraprocedural nor postprocedural adverse events.
Conclusion:
TRS-assisted ESD is a feasible option when used in the rectum, with promising result in terms of efficacy and safety outcomes. Nevertheless, our pilot study underlines few technical limitations of the present platform that need to be overcome before the system could be widely and routinely used.
Impact of artificial intelligence on colorectal polyp detection Antonelli, Giulio; Badalamenti, Matteo; Hassan, Cesare ...
Baillière's best practice & research. Clinical gastroenterology,
June-August 2021, 2021-06-00, 20210601, Letnik:
52-53
Journal Article
Recenzirano
Since colonoscopy and polypectomy were introduced, Colorectal Cancer (CRC) incidence and mortality decreased significantly. Although we have entered the era of quality measurement and improvement, ...literature shows that a considerable amount of colorectal neoplasia is still missed by colonoscopists up to 25%, leading to an high rate of interval colorectal cancer that account for nearly 10% of all diagnosed CRC. Two main reasons have been recognised: recognition failure and mucosal exposure. For this purpose, Artificial Intelligence (AI) systems have been recently developed that identify a “hot” area during the endoscopic examination. In retrospective studies, where the systems are tested with a batch of unknown images, deep learning systems have shown very good performances, with high levels of accuracy. Of course, this setting may not reflect actual clinical practice where different pitfalls can occur, like suboptimal bowel preparation or poor examination technique. For this reason, a number of randomised clinical trials have recently been published where AI was tested in real time during endoscopic examinations. We present here an overview on recent literature addressing the performance of Computer Assisted Detection (CADe) of colorectal polyps in colonoscopy.
Background and aimsArtificial intelligence has been shown to increase adenoma detection rate (ADR) as the main surrogate outcome parameter of colonoscopy quality. To which extent this effect may be ...related to physician experience is not known. We performed a randomised trial with colonoscopists in their qualification period (AID-2) and compared these data with a previously published randomised trial in expert endoscopists (AID-1).MethodsIn this prospective, randomised controlled non-inferiority trial (AID-2), 10 non-expert endoscopists (<2000 colonoscopies) performed screening/surveillance/diagnostic colonoscopies in consecutive 40–80 year-old subjects using high-definition colonoscopy with or without a real-time deep-learning computer-aided detection (CADe) (GI Genius, Medtronic). The primary outcome was ADR in both groups with histology of resected lesions as reference. In a post-hoc analysis, data from this randomised controlled trial (RCT) were compared with data from the previous AID-1 RCT involving six experienced endoscopists in an otherwise similar setting.ResultsIn 660 patients (62.3±10 years; men/women: 330/330) with equal distribution of study parameters, overall ADR was higher in the CADe than in the control group (53.3% vs 44.5%; relative risk (RR): 1.22; 95% CI: 1.04 to 1.40; p<0.01 for non-inferiority and p=0.02 for superiority). Similar increases were seen in adenoma numbers per colonoscopy and in small and distal lesions. No differences were observed with regards to detection of non-neoplastic lesions. When pooling these data with those from the AID-1 study, use of CADe (RR 1.29; 95% CI: 1.16 to 1.42) and colonoscopy indication, but not the level of examiner experience (RR 1.02; 95% CI: 0.89 to 1.16) were associated with ADR differences in a multivariate analysis.ConclusionsIn less experienced examiners, CADe assistance during colonoscopy increased ADR and a number of related polyp parameters as compared with the control group. Experience appears to play a minor role as determining factor for ADR.Trial registration numberNCT:04260321.
The benefits of prophylactic clipping to prevent bleeding after polypectomy are unclear. We conducted an updated meta-analysis of randomized trials to assess the efficacy of clipping in preventing ...bleeding after polypectomy, overall and according to polyp size and location.
We searched the MEDLINE/PubMed, Embase, and Scopus databases for randomized trials that compared the effects of clipping vs not clipping to prevent bleeding after polypectomy. We performed a random-effects meta-analysis to generate pooled relative risks (RRs) with 95% CIs. Multilevel random-effects metaregression analysis was used to combine data on bleeding after polypectomy and estimate associations between rates of bleeding and polyp characteristics.
We analyzed data from 9 trials, comprising 71897 colorectal lesions (22.5% 20 mm or larger; 49.2% with proximal location). Clipping, compared with no clipping, did not significantly reduce the overall risk of postpolypectomy bleeding (2.2% with clipping vs 3.3% with no clipping; RR, 0.69; 95% confidence interval CI, 0.45–1.08; P = .072). Clipping significantly reduced risk of bleeding after removal of polyps that were 20 mm or larger (4.3% had bleeding after clipping vs 7.6% had bleeding with no clipping; RR, 0.51; 95% CI, 0.33–0.78; P = .020) or that were in a proximal location (3.0% had bleeding after clipping vs 6.2% had bleeding with no clipping; RR, 0.53; 95% CI, 0.35–0.81; P < .001). In multilevel metaregression analysis that adjusted for polyp size and location, prophylactic clipping was significantly associated with reduced risk of bleeding after removal of large proximal polyps (RR, 0.37; 95% CI, 0.22–0.61; P = .021) but not small proximal lesions (RR, 0.88; 95% CI, 0.48–1.62; P = .581).
In a meta-analysis of randomized trials, we found that routine use of prophylactic clipping does not reduce risk of postpolypectomy bleeding overall. However, clipping appeared to reduce bleeding after removal of large (more than 20 mm) proximal lesions.
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Colonoscopy remains the standard strategy for screening for colorectal cancer around the world due to its efficacy in both detecting adenomatous or pre-cancerous lesions and the capacity to remove ...them intra-procedurally. Computer-aided detection and diagnosis (CAD), thanks to the brand new developed innovations of artificial intelligence, and especially deep-learning techniques, leads to a promising solution to human biases in performance by guarantying decision support during colonoscopy. The application of CAD on real-time colonoscopy helps increasing the adenoma detection rate, and therefore contributes to reduce the incidence of interval cancers improving the effectiveness of colonoscopy screening on critical outcome such as colorectal cancer related mortality. Furthermore, a significant reduction in costs is also expected. In addition, the assistance of the machine will lead to a reduction of the examination time and therefore an optimization of the endoscopic schedule. The aim of this opinion review is to analyze the clinical applications of CAD and artificial intelligence in colonoscopy, as it is reported in literature, addressing evidence, limitations, and future prospects.
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