Nomenclature and semantic description of vascular lesions in small bowel capsule endoscopy: an international Delphi consensus statement

Capsule endoscopy for obscure gastrointestinal bleed in the tropics: A single-center experience on 350 patients

BACKGROUND

Obscure gastrointestinal bleed (OGIB), now called small bowel bleed (SBB), comprises 5% to 10% of all gastrointestinal (GI) bleed episodes and capsule endoscopy (CE) is a tool for its evaluation. Studies on CE in a large sample of SBB patients from the tropics are limited.

METHODS

We did a retrospective analysis of a prospectively maintained database of patients with SBB undergoing CE using PillCam or MiroCam CE.

RESULTS

Of 350 patients (age 52.4 ± 17.4 years; 248 [70.9%] male) undergoing CE, 243 (69.4%) and 107 (30.6%) had overt and occult SBB, respectively. CE detected lesions in 244 (69.7%) patients (single lesion in 172 [49.1%]; multiple in 72 [20.6%]). The single lesions included vascular malformations (52, 14.9%), ulcer/erosion (47, 13.4%), tumor (24, 6.9%), hookworm (19, 5.4%), stricture (15, 4.3%), hemobilia (1, 0.3%) and blood without identifiable lesion (9, 2.6%). Of 72 with multiple lesions, ulcer with stricture was the commonest finding (n = 43, 12.3%). No abnormality was detected in 106 (30.3%) patients. The frequency of lesion detection was comparable among patients with overt and occult SBB (173/243, 71.2% vs. 71/107, 66.3%, respectively; p = 0.4). Younger patients (0 to 39 years) more often had multiple lesions on CE than the older (≥ 40 years) ones (26/76, 34.2% vs. 46/228, 20.2%, respectively; p = 0.001).

CONCLUSION

CE has a high diagnostic yield in SBB in the tropics, regardless of the type of bleed or of CE brand and the duration of recording. Multiple lesions associated with SBB are commoner among younger (< 40 years) patients.

Pan-intestinal capsule endoscopy as first-line procedure in patients with suspected mid or lower gastrointestinal bleeding

BACKGROUND

Pan-intestinal capsule endoscopy (PCE) evaluates the small bowel and colon noninvasively. This study evaluated diagnostic accuracy and safety of PCE vs. colonoscopy as first-line examination in suspected mid-lower gastrointestinal bleeding (MLGIB).

METHODS

In this prospective, single-center, single-blinded cohort study, consecutive patients with suspected MLGIB underwent PCE followed by same-day colonoscopy. Diagnostic accuracy for potentially hemorrhagic lesions (PHLs; combined diagnosis by PCE + colonoscopy) and incidence of adverse events were assessed.

RESULTS

100 patients were included (median age 70 [range 18-92] years; 65% female). PHLs were diagnosed in 46 patients, including small-bowel and/or colon angioectasias in 32. PCE correctly identified 54 individuals without PHLs, and 95.7% (44/46) of those with PHLs vs. 50.0% (23/46) for colonoscopy (P<0.01). PHLs were detected by PCE alone in 65.2% (30/46), both examinations in 28.3% (13/46), and colonoscopy alone in 6.5% (3/46). PHLs were diagnosed at the ileocolonic region in 28% of patients, with PCE diagnosing 25/28 cases (89.3%) and colonoscopy diagnosing 23/28 (82.1%; P=0.13). Interventional procedures were performed at colonoscopy in 13/81 patients with iron-deficiency anemia (16.0%) vs. 6/19 patients with overt bleeding (31.6%; P<0.01). No significant adverse events occurred with PCE vs. 2% with colonoscopy.

CONCLUSIONS

In patients with MLGIB, PCE avoided further invasive procedures in >50% of patients. PCE was safe and more effective than colonoscopy in identifying PHL both in the small bowel and colon. These results support the potential use of PCE as first-line examination in patients with suspected MLGIB.

The professional background of a referring physician predicts the diagnostic yield of small bowel capsule endoscopy in suspected small bowel bleeding

Background and study aims The diagnostic yield of small-bowel capsule endoscopy (SBCE) in suspected small bowel bleeding (SSBB) is highly variable. Different reimbursement systems and equipment costs also limit SBCE use in clinical practice. Thus, minimizing non-diagnostic procedures is advisable. This study aimed to assess the SBCE diagnostic yield and identify factors predicting diagnostic findings in a cohort of patients with SSBB. Patients and methods In this retrospective cohort study, we analyzed the medical records of patients who consecutively underwent SBCE for SSBB over 9 years. By logistic regression, we identified covariates predicting diagnostic findings at SBCE. Finally, we performed a post-hoc cost analysis based on previous gastroenterologist or endoscopist consultations versus direct SBCE ordering by other specialists. Results The final analysis included 584 patients. Most SBCEs were ordered by a gastroenterologist or endoscopist (74%). The number of SBCEs without any finding was significantly lower in the gastroenterologist/endoscopist group P <0.001). The SBCE diagnostic yield ordered by a gastroenterologist or endoscopist was significantly higher than that by other specialists (63% vs 52%, odds ratio [OR] 1.57; 95% confidence interval [CI] 1.07-2.26, P =0.019). At multivariate analysis, older age (OR 1.7, 95%CI 1.2-2.4, P =0.005), anemia (OR 4.9, 95%CI 1.9-12, P =0.001), small bowel transit time (OR 1, 95%CI 1-1.02, P =0.039), and referring physician (OR 1.8, 95%CI 1.1-2.7, P =0.003) independently predicted diagnostic findings. Implementing prior gastroenterologist or endoscopist referral vs direct SBCE ordering would reduce medical expenditures by 16%. Conclusions The professional background of referring physicians significantly improves the diagnostic yield of SBCE and contributes to controlling public health costs.

Deep Learning and Minimally Invasive Endoscopy: Automatic Classification of Pleomorphic Gastric Lesions in Capsule Endoscopy

INTRODUCTION

Capsule endoscopy (CE) is a minimally invasive examination for evaluating the gastrointestinal tract. However, its diagnostic yield for detecting gastric lesions is suboptimal. Convolutional neural networks (CNNs) are artificial intelligence models with great performance for image analysis. Nonetheless, their role in gastric evaluation by wireless CE (WCE) has not been explored.

METHODS

Our group developed a CNN-based algorithm for the automatic classification of pleomorphic gastric lesions, including vascular lesions (angiectasia, varices, and red spots), protruding lesions, ulcers, and erosions. A total of 12,918 gastric images from 3 different CE devices (PillCam Crohn's; PillCam SB3; OMOM HD CE system) were used from the construction of the CNN: 1,407 from protruding lesions; 994 from ulcers and erosions; 822 from vascular lesions; and 2,851 from hematic residues and the remaining images from normal mucosa. The images were divided into a training (split for three-fold cross-validation) and validation data set. The model's output was compared with a consensus classification by 2 WCE-experienced gastroenterologists. The network's performance was evaluated by its sensitivity, specificity, accuracy, positive predictive value and negative predictive value, and area under the precision-recall curve.

RESULTS

The trained CNN had a 97.4% sensitivity; 95.9% specificity; and positive predictive value and negative predictive value of 95.0% and 97.8%, respectively, for gastric lesions, with 96.6% overall accuracy. The CNN had an image processing time of 115 images per second.

DISCUSSION

Our group developed, for the first time, a CNN capable of automatically detecting pleomorphic gastric lesions in both small bowel and colon CE devices.

Predictive Model for Positive Video Capsule Endoscopy in Iron Deficiency Anemia

BACKGROUND AND AIMS

Bleeding from the gastrointestinal tract can contribute to the development of iron deficiency anemia (IDA) among individuals without another obvious source of bleeding. In order to identify patients most likely to benefit from examination of the small bowel, our aim was to create a risk score for positive video capsule endoscopy (VCE) in IDA utilizing a multicenter collection of studies.

METHODS

We performed a retrospective multicenter study utilizing VCE studies performed for an indication of IDA between 1/1/2005 and 7/31/2018. VCE findings were graded based on the P0-P2 grading system. The primary outcome of interest was a positive (P2) VCE. Data were analyzed with Student's t test for continuous variables and the Fisher's exact test for categorical variables. Logistic regression was used to identify independent associations with positive VCE.

RESULTS

In total, 765 VCE procedures were included with 355 (46.5%) male subjects and a median age of 63.2 (SD 15.3) years. One hundred ninety studies (24.8%) were positive (P2) for small bowel bleeding. Four variables associated with positive VCE which were incorporated into a point scoring system: (+) 1 for age ≥ 66 years, active smoking and cardiac arrythmia and (-) 1 for preceding hemoglobin level ≥ 8.5. The risk probabilities for positive VCE-assigned scores - 1, 0, 1, and 2 + were 12.3% (95% CI 7.3-17.3%), 20% (14.9-25.1%), 34.8% (28.6-41%), and 39% (30-47.8%).

CONCLUSION

In order to improve the diagnostic yield of capsule examinations, risk factors should be applied to clinical decision-making. We created a risk score for positive VCE in IDA, including the risk factors of age, smoking, history of cardiac arrythmia, and preceding hemoglobin level.

Small Bowel Capsule Endoscopy: Experience from a single large tertiary care centre

Background and study aims Capsule endoscopy (CE) has transformed examination of the small bowel (SB), once considered a dark continent. The present study aimed to describe the indications, diagnostic yield, practical issues and complications of CE in one of the largest tertiary center in India. Patients and methods This retrospective analysis from a prospectively maintained database, conducted from January 2013 to June 2021 included 1155 CEs performed during this period. Patient medical records were reviewed for indications, results, and complications of CE. Results A total of 1154 patients (809 males and 345 females), mean age 53 years (range 6-87 years), one capsule got stuck in the esophagus, were included in the study. Active SB bleeding had no effect on SB transit time (324.7±161 minutes, n = 137 patients with active bleed vs 310.6±166.9 minutes, n = 1017 patients without active bleed; P = 0.35). The indication and diagnostic yield (DY) of CE were potential overt SB bleed (68.6% & 43.9%), potential occult SB bleed (8.2% and 40%), chronic diarrhea (7.9% and 28.4%), abdominal pain (6.5% and 21.3%), anemia (5.9% and 57.9%), and suspected/known case of Crohn's disease (2.3% & 56.5%) respectively. The DY for patients with age ≥60 years was similar to those with age < 60 years (61.9% vs. 51.8% respectively; P = 0.4). 21 patients (1.8%) had capsule retention of which six (0.5%) had to be referred for surgery. Conclusions CE is a safe and effective investigation with ever increasing range of indications. Potential SB bleed remains the most common indication for CE with high detection rate.

Gastrointestinal angiodysplasias diagnosed using video capsule endoscopy in 15 dogs

BACKGROUND

Angiodysplasia (AGD) is rarely diagnosed in dogs with gastrointestinal bleeding (GIB) and is reported in case reports in dogs.

OBJECTIVE

Describe signalment, clinical and diagnostic features of dogs with gastrointestinal (GI) AGD diagnosed by video capsule endoscopy (VCE).

ANIMALS

Dogs with overt or suspected GIB which underwent VCE.

METHODS

Dogs for which a VCE was submitted for overt or suspected GIB from 2016 to 2021 were selected retrospectively. Medical records and full-length VCE recordings where AGDs were initially detected, were reviewed by 2 trained internists. AGD was considered definitive if 2 readers detected it. Signalment, clinical signs, blood work, medications, concurrent diseases, findings of previous conventional endoscopy, and surgical exploration (if applicable) of dogs with AGD were recorded.

RESULTS

Definitive AGD was diagnosed in 15 of 291 (5%) dogs (12 males, 3 females). Twelve (80%) had overt GIB, 11 (73%) had hematochezia, and 6 (40%) had microcytic and hypochromic anemia. AGD was missed by conventional endoscopy in 9/9 dogs and exploratory surgery in 3/3 dogs. Thirteen capsules were administered by mouth (1 incomplete study), and 2 via endoscopy directly into the duodenum. AGD was visualized in the stomach of 3 dogs, in the small intestine of 4, and in the colon of 13 dogs.

CONCLUSION AND CLINICAL IMPORTANCE

Although rare, AGD should be considered in dogs with suspected GIB after a negative conventional endoscopy or surgical exporation. Video capsuel endoscopy appears to be a sensitive test to identify AGD within the GI tract.

Enteroscopy in diagnosis and treatment of small bowel bleeding: A Delphi expert consensus

BACKGROUND

Enteroscopy plays an important role in the management of small bowel bleeding. However, current guidelines are not specifically designed for small bowel bleeding and recommendations from different international societies do not always align. Consequently, there is heterogeneity in the definitions of clinical entities, clinical practice policies, and adherence to guidelines among clinicians. This represents an obstacle to providing the best patient care and to obtain homogeneous data for clinical research.

AIMS

The aims of the study were to establish a consensus on the definitions of bleeding entities and on the role of enteroscopy in the management of small bowel bleeding using a Delphi process.

METHODS

A core group of eight experts in enteroscopy identified five main topics of small bowel bleeding management and drafted statements on each topic. An expert panel of nine gastroenterologists participated in three rounds of the Delphi process, together with the core group.

RESULTS

A total of 33 statements were approved after three rounds of Delphi voting.

CONCLUSION

This Delphi consensus proposes clear definitions and a unifying strategy to standardize the management of small bowel bleeding. Furthermore, it provides a useful guide in daily practice for both clinical and technical issues of enteroscopy.

Quality indicators for capsule endoscopy and deep enteroscopy

BACKGROUND AND AIMS

Capsule endoscopy (CE) and deep enteroscopy (DE) can be useful for diagnosing and treating suspected small-bowel disease. Guidelines and detailed recommendations exist for the use of CE/DE, but comprehensive quality indicators are lacking. The goal of this task force was to develop quality indicators for appropriate use of CE/DE by using a modified RAND/UCLA Appropriateness Method.

METHODS

An expert panel of 7 gastroenterologists with diverse practice experience was assembled to identify quality indicators. A literature review was conducted to develop a list of proposed quality indicators applicable to preprocedure, intraprocedure, and postprocedure periods. The panelists reviewed the literature; identified and modified proposed quality indicators; rated them on the basis of scientific evidence, validity, and necessity; and determined proposed performance targets. Agreement and consensus with the proposed indicators were verified using the RAND/UCLA Appropriateness Method.

RESULTS

The voting procedure to prioritize metrics emphasized selecting measures to improve quality and overall patient care. Panelists rated indicators on the perceived appropriateness and necessity for clinical practice. After voting and discussion, 2 quality indicators ranked as inappropriate or uncertain were excluded. Each quality indicator was categorized by measure type, performance target, and summary of evidence. The task force identified 13 quality indicators for CE and DE.

CONCLUSIONS

Comprehensive quality indicators have not existed for CE or DE. The task force identified quality indicators that can be incorporated into clinical practice. The panel also addressed existing knowledge gaps and posed research questions to better inform future research and quality guidelines for these procedures.

Quality Indicators for Capsule Endoscopy and Deep Enteroscopy

INTRODUCTION

Capsule endoscopy (CE) and deep enteroscopy (DE) can be useful for diagnosing and treating suspected small-bowel disease. Guidelines and detailed recommendations exist for the use of CE/DE, but comprehensive quality indicators are lacking. The goal of this task force was to develop quality indicators for appropriate use of CE/DE by using a modified RAND/UCLA Appropriateness Method.

METHODS

An expert panel of 7 gastroenterologists with diverse practice experience was assembled to identify quality indicators. A literature review was conducted to develop a list of proposed quality indicators applicable to preprocedure, intraprocedure, and postprocedure periods. The panelists reviewed the literature; identified and modified proposed quality indicators; rated them on the basis of scientific evidence, validity, and necessity; and determined proposed performance targets. Agreement and consensus with the proposed indicators were verified using the RAND/UCLA Appropriateness Method.

RESULTS

The voting procedure to prioritize metrics emphasized selecting measures to improve quality and overall patient care. Panelists rated indicators on the perceived appropriateness and necessity for clinical practice. After voting and discussion, 2 quality indicators ranked as inappropriate or uncertain were excluded. Each quality indicator was categorized by measure type, performance target, and summary of evidence. The task force identified 13 quality indicators for CE and DE.

DISCUSSION

Comprehensive quality indicators have not existed for CE or DE. The task force identified quality indicators that can be incorporated into clinical practice. The panel also addressed existing knowledge gaps and posed research questions to better inform future research and quality guidelines for these procedures.

Nomenclature and Definition of Atrophic Lesions in Small Bowel Capsule Endoscopy: A Delphi Consensus Statement of the International CApsule endoscopy REsearch (I-CARE) Group

(1) Background: Villous atrophy is an indication for small bowel capsule endoscopy (SBCE). However, SBCE findings are not described uniformly and atrophic features are sometimes not recognized; (2) Methods: The Delphi technique was employed to reach agreement among a panel of SBCE experts. The nomenclature and definitions of SBCE lesions suggesting the presence of atrophy were decided in a core group of 10 experts. Four images of each lesion were chosen from a large SBCE database and agreement on the correspondence between the picture and the definition was evaluated using the Delphi method in a broadened group of 36 experts. All images corresponded to histologically proven mucosal atrophy; (3) Results: Four types of atrophic lesions were identified: mosaicism, scalloping, folds reduction, and granular mucosa. The core group succeeded in reaching agreement on the nomenclature and the descriptions of these items. Consensus in matching the agreed definitions for the proposed set of images was met for mosaicism (88.9% in the first round), scalloping (97.2% in the first round), and folds reduction (94.4% in the first round), but granular mucosa failed to achieve consensus (75.0% in the third round); (4) Conclusions: Consensus among SBCE experts on atrophic lesions was met for the first time. Mosaicism, scalloping, and folds reduction are the most reliable signs, while the description of granular mucosa remains uncertain.

Development and Validation of an Artificial Intelligence Model for Small Bowel Capsule Endoscopy Video Review

IMPORTANCE

Reading small bowel capsule endoscopy (SBCE) videos is a tedious task for clinicians, and a new method should be applied to solve the situation.

OBJECTIVES

To develop and evaluate the performance of a convolutional neural network algorithm for SBCE video review in real-life clinical care.

DESIGN, SETTING, AND PARTICIPANTS

In this multicenter, retrospective diagnostic study, a deep learning neural network (SmartScan) was trained and validated for the SBCE video review. A total of 2927 SBCE examinations from 29 medical centers were used to train SmartScan to detect 17 types of CE structured terminology (CEST) findings from January 1, 2019, to June 30, 2020. SmartScan was later validated with conventional reading (CR) and SmartScan-assisted reading (SSAR) in 2898 SBCE examinations collected from 22 medical centers. Data analysis was performed from January 25 to December 31, 2021.

EXPOSURE

An artificial intelligence-based tool for interpreting clinical images of SBCE.

MAIN OUTCOMES AND MEASURES

The detection rate and efficiency of CEST findings detected by SSAR and CR were compared.

RESULTS

A total of 5825 SBCE examinations were retrospectively collected; 2898 examinations (1765 male participants [60.9%]; mean [SD] age, 49.8 [15.5] years) were included in the validation phase. From a total of 6084 CEST-classified SB findings, SSAR detected 5834 findings (95.9%; 95% CI, 95.4%-96.4%), significantly higher than CR, which detected 4630 findings (76.1%; 95% CI, 75.0%-77.2%). SmartScan-assisted reading achieved a higher per-patient detection rate (79.3% [2298 of 2898]) for CEST findings compared with CR (70.7% [2048 of 2298]; 95% CI, 69.0%-72.3%). With SSAR, the mean (SD) number of images (per SBCE video) requiring review was reduced to 779.2 (337.2) compared with 27 910.8 (12 882.9) with CR, for a mean (SD) reduction rate of 96.1% (4.3%). The mean (SD) reading time with SSAR was shortened to 5.4 (1.5) minutes compared with CR (51.4 [11.6] minutes), for a mean (SD) reduction rate of 89.3% (3.1%).

CONCLUSIONS AND RELEVANCE

This study suggests that a convolutional neural network-based algorithm is associated with an increased detection rate of SBCE findings and reduced SBCE video reading time.

Evaluation by a Machine Learning System of Two Preparations for Small Bowel Capsule Endoscopy: The BUBS (Burst Unpleasant Bubbles with Simethicone) Study

Background: Bubbles often mask the mucosa during capsule endoscopy (CE). Clinical scores assessing the cleanliness and the amount of bubbles in the small bowel (SB) are poorly reproducible unlike machine learning (ML) solutions. We aimed to measure the amount of bubbles with ML algorithms in SB CE recordings, and compare two polyethylene glycol (PEG)-based preparations, with and without simethicone, in patients with obscure gastro-intestinal bleeding (OGIB). Patients & Methods: All consecutive outpatients with OGIB from a tertiary care center received a PEG-based preparation, without or with simethicone, in two different periods. The primary outcome was a difference in the proportions (%) of frames with abundant bubbles (>10%) along the full-length video sequences between the two periods. SB CE recordings were analyzed by a validated computed algorithm based on a grey-level of co-occurrence matrix (GLCM), to assess the abundance of bubbles in each frame. Results: In total, 105 third generation SB CE recordings were analyzed (48 without simethicone and 57 with simethicone-added preparations). A significant association was shown between the use of a simethicone-added preparation and a lower abundance of bubbles along the SB (p = 0.04). A significantly lower proportion of “abundant in bubbles” frames was observed in the fourth quartile (30.5% vs. 20.6%, p = 0.02). There was no significant impact of the use of simethicone in terms of diagnostic yield, SB transit time and completion rate. Conclusion: An accurate and reproducible computed algorithm demonstrated significant decrease in the abundance of bubbles along SB CE recordings, with a marked effect in the last quartile, in patients for whom simethicone had been added in PEG-based preparations, compared to those without simethicone.

CC-CLEAR (Colon Capsule Cleansing Assessment and Report): the novel scale to evaluate the clinical impact of bowel preparation in capsule colonoscopy - a multicentric validation study

BACKGROUND

Colon Capsule Cleansing Assessment and Report (CC-CLEAR) is a novel quantitative bowel preparation scale for colon capsule.

AIM

The aim of this study is to validate the association between CC-CLEAR's classification and major CC outcomes: lesion detection rate, surveillance recommendations and post-CC endoscopic treatment.

METHODS

Multicentric cohort of consecutive CCs. An expert's panel decided post-CC recommendations. Data included CC-CLEAR and Leighton-REX scales. Major CC outcomes were associated with the different cleansing grades.

RESULTS

From 168 CC's included, findings were reported in 123 (73.2%), 67 (54.4%) of those being colorectal polyps. CC-CLEAR influenced CC's lesion detection (OR 1.25 95% IC [1.07-1.46], p-value .004) and polyp detection rate (OR 1.22 95% IC [1.04-1.43], p-value.014). Thirty-two (19%) post-CC colonoscopies were recommended, including 22 (68.75%) with at least one polypectomy. CC-CLEAR was associated with post-CC colonoscopy treatment (OR 1.40 95% IC [1.07-1.84], p-value .015). Regarding surveillance, CC-CLEAR influenced the decision for immediate CC repetition (OR 0.21 95% IC [0.12-0.36], p-value < .001) and the recommendation for CC in 3-5 years' time (OR 1.47 95% IC [1.50-1.86], p-value < .002). The Leighton-Rex scale was not correlated with major CC outcomes.

CONCLUSION

CC-CLEAR impacts major CC outcomes: lesion detection, surveillance recommendations and post-CC endoscopic treatment.

Artificial intelligence within the small bowel: are we lagging behind?

PURPOSE OF REVIEW

The use of artificial intelligence in small bowel capsule endoscopy is expanding. This review focusses on the use of artificial intelligence for small bowel pathology compared with human data and developments to date.

RECENT FINDINGS

The diagnosis and management of small bowel disease has been revolutionized with the advent of capsule endoscopy. Reading of capsule endoscopy videos however is time consuming with an average reading time of 40 min. Furthermore, the fatigued human eye may miss subtle lesions including indiscreet mucosal bulges. In recent years, artificial intelligence has made significant progress in the field of medicine including gastroenterology. Machine learning has enabled feature extraction and in combination with deep neural networks, image classification has now materialized for routine endoscopy for the clinician.

SUMMARY

Artificial intelligence is in built within the Navicam-Ankon capsule endoscopy reading system. This development will no doubt expand to other capsule endoscopy platforms and capsule endoscopies that are used to visualize other parts of the gastrointestinal tract as a standard. This wireless and patient friendly technique combined with rapid reading platforms with the help of artificial intelligence will become an attractive and viable choice to alter how patients are investigated in the future.

RHEMITT score: Predicting the risk of mid gastrointestinal rebleeding after small bowel capsule endoscopy: A prospective validation

BACKGROUND AND AIM

The RHEMITT score (Renal disease; Heart failure; Endoscopic findings; Major bleeding; Incomplete SBCE; Tobacco; Treatment by enteroscopy) was the first score to accurately predict the individual risk of small bowel rebleeding after capsule endoscopy (SBCE). The aim of the study is on the prospective validation of the RHEMITT score.

METHODS

Cohort of consecutive patients with mid-gastrointestinal bleeding (MGIB) submitted to SBCE and followed prospectively, during at least 12 months, since 2017 until 2020. Rebleeding was defined as an overt bleeding event (melena or hematochezia) or a hemoglobin decrease of at least 2 g/dL. The RHEMITT score was calculated for each patient and the rebleeding rates compared. The performance of the score was tested by calculating the area under curve of the receiver operator characteristic curve. A rebleeding-free survival was assessed, corresponding to the period between the date of SBCE and the date of the first post-SBCE rebleeding event.

RESULTS

We included 162 patients, 102 (62.9%) were female, with a mean age of 64 years old. The sensitivities and specificities of the score grades for predicting rebleeding were as following: for low-risk patients, 0% (0-10%) and 28.8% (21.1-36.5%); for intermediate-risk patients, 23.3% (8.2-38.4%) and 72% (64.3-79.7%); for high-risk patients, 76.7% (61.6-91.8%) and 99.2% (97.7-100%), corresponding to an area under curve of the receiver operator characteristic of 0.988 (P < 0.001). Kaplan-Meyer plots were statistically different according to the attributed risk (log-rank P value <0.001; Breslow-Wilcoxon P value <0.001).

CONCLUSION

The RHEMITT score performed with excellent discriminative power in predicting rebleeding risk, and we herewith propose a surveillance of MGIB patients guided by the RHEMITT score.

Effect of Different Modalities of Purgative Preparation on the Diagnostic Yield of Small Bowel Capsule for the Exploration of Suspected Small Bowel Bleeding: A Multicenter Randomized Controlled Trial

INTRODUCTION

The aim of our study was to compare clear liquid diet with 2 different polyethylene glycol (PEG)-based bowel preparation methods regarding diagnostic yield of small bowel capsule endoscopy (SBCE) in patients with suspected small bowel bleeding (SBB).

METHODS

In this prospective multicenter randomized controlled trial, consecutive patients undergoing SBCE for suspected SBB between September 2010 and February 2016 were considered. Patients were randomly assigned to standard regimen, that is, clear fluids only (prep 1), standard regimen plus 500 mL PEG after SBCE ingestion (prep 2), or standard regimen plus 2 L PEG plus 500 mL PEG after SBCE ingestion (prep 3). The primary outcome was the detection of at least one clinically significant lesion in the small bowel. The quality of small bowel cleansing was assessed. A questionnaire on the clinical tolerance was filled by the patients.

RESULTS

We analyzed 834 patients. No significant difference was observed for detection of P1 or P2 small bowel lesions between prep1 group (40.5%), prep 2 group (40.2%), and prep 3 group (38.5%). Small bowel cleansing was improved in prep 2 and 3 groups compared with that in prep 1 group. Compliance to the preparation and tolerance was better in prep 2 group than in prep 3 group.

DISCUSSION

Small bowel purgative before SBCE allowed better quality of cleansing. However, it did not improve diagnostic yield of SBCE for suspected SBB.

Artificial intelligence and capsule endoscopy: automatic detection of vascular lesions using a convolutional neural network

Background

Capsule endoscopy (CE) is the first line for evaluation of patients with obscure gastrointestinal bleeding. A wide range of small intestinal vascular lesions with different hemorrhagic potential are frequently found in these patients. Nevertheless, reading CE exams is time-consuming and prone to errors. Convolutional neural networks (CNN) are artificial intelligence tools with high performance levels in image analysis. This study aimed to develop a CNN-based model for identification and differentiation of vascular lesions with distinct hemorrhagic potential in CE images.

Methods

The development of the CNN was based on a database of CE images. This database included images of normal small intestinal mucosa, red spots, and angiectasia/varices. The hemorrhagic risk was assessed by Saurin's classification. For CNN development, 11,588 images (9525 normal mucosa, 1026 red spots, and 1037 angiectasia/varices) were ultimately extracted. Two image datasets were created for CNN training and testing.

Results

The network was 91.8% sensitive and 95.9% specific for detection of vascular lesions, providing accurate predictions in 94.4% of cases. In particular, the CNN had a sensitivity and specificity of 97.1% and 95.3%, respectively, for detection of red spots. Detection of angiectasia/varices occurred with a sensitivity of 94.1% and a specificity of 95.1%. The CNN had a frame reading rate of 145 frames/sec.

Conclusions

The developed algorithm is the first CNN-based model to accurately detect and distinguish enteric vascular lesions with different hemorrhagic risk. CNN-assisted CE reading may improve the diagnosis of these lesions and overall CE efficiency.

A guide for assessing the clinical relevance of findings in small bowel capsule endoscopy: analysis of 8064 answers of international experts to an illustrated script questionnaire

BACKGROUND AND AIM

Although recommended, the P-score used for assessing the pertinence / relevance of findings seen in small bowel (SB) capsule endoscopy (CE) is based on a low level of knowledge. The aim of this study was to evaluate the clinical relevance of the most frequent SBCE findings through an illustrated script questionnaire.

MATERIALS AND METHODS

Sixteen types of SBCE findings were illustrated four times each in three different settings (occult and overt obscure gastrointestinal bleeding and suspected Crohn's disease), and with a variable number (n = 1/n = 2-5/n ≥ 6), thus providing a questionnaire with 192 scenarios and 576 illustrated questions. Fifteen international experts were asked to rate the finding's relevance for each question as very unlikely (-2) / unlikely (-1) / doubtful (0) / likely (+1) / very likely (+2). The median score (≤-0.75, between -0.75 and 0.75, or ≥0.75) obtained for each scenario determined a low (P0), intermediate (P1) or high (P2) relevance, respectively.

RESULTS

8064 answers were analyzed. Participation and completion rates were 93% and 100%, respectively. In overt or occult OGIB, resultant P2 findings were 'typical angiectasia', 'deep ulceration', 'stenosis', and'blood', whatever their numbers, and 'superficial ulcerations' when multiple. While in suspected CD, consensus P2 lesions were 'deep ulceration' and 'stenosis' whatever their numbers, and 'aphthoid erosions' and 'superficial ulcerations' when multiple.

CONCLUSION

This study establishes a guide for the evaluation of relevance of SBCE findings. It represents a step forward for SB-CE interpretation and is intended to be used as a tool for teaching and academic research.

Deep learning and capsule endoscopy: automatic identification and differentiation of small bowel lesions with distinct haemorrhagic potential using a convolutional neural network

OBJECTIVE

Capsule endoscopy (CE) is pivotal for evaluation of small bowel disease. Obscure gastrointestinal bleeding most often originates from the small bowel. CE frequently identifies a wide range of lesions with different bleeding potentials in these patients. However, reading CE examinations is a time-consuming task. Convolutional neural networks (CNNs) are highly efficient artificial intelligence tools for image analysis. This study aims to develop a CNN-based model for identification and differentiation of multiple small bowel lesions with distinct haemorrhagic potential using CE images.

DESIGN

We developed, trained, and validated a denary CNN based on CE images. Each frame was labelled according to the type of lesion (lymphangiectasia, xanthomas, ulcers, erosions, vascular lesions, protruding lesions, and blood). The haemorrhagic potential was assessed by Saurin's classification. The entire dataset was divided into training and validation sets. The performance of the CNN was measured by the area under the receiving operating characteristic curve, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

A total of 53 555 CE images were included. The model had an overall accuracy of 99%, a sensitivity of 88%, a specificity of 99%, a PPV of 87%, and an NPV of 99% for detection of multiple small bowel abnormalities and respective classification of bleeding potential.

CONCLUSION

We developed and tested a CNN-based model for automatic detection of multiple types of small bowel lesions and classification of the respective bleeding potential. This system may improve the diagnostic yield of CE for these lesions and overall CE efficiency.

Scoring systems in clinical small-bowel capsule endoscopy: all you need to know!

Capsule endoscopy (CE) emerged out of the pressing clinical need to image the small bowel (SB) in cases of midgut bleeding and provide an overall comfortable and reliable gastrointestinal (GI) diagnosis 1. Since its wider adoption in clinical practice, significant progress has been made in several areas including software development, hardware features and clinical indications, while innovative applications of CE never cease to appear 2 3. Currently, several manufacturers provide endoscopic capsules with more or less similar technological features 4. Although there is engaging and continuous academic and industry-fueled R&D, promising furtherment of CE technology 4 5, the current status of clinical CE remains that of by and large an imaging modality. Clinical relevance of CE images is cornerstone in the decision-making process for medical management. In one of the larger to date SB CE studies, 4,206 abnormal images were detected in 3,280 patients 6. Thus, CE leads to the identification of a large amount of potential pathology, some of which are pertinent (or relevant) while some (probably the majority) are not.

Soon artificial intelligence (AI) is likely to carry out several roles currently performed by humans; in fact, we are witnessing only the first stages of a transition in the clinical adoption of AI-based solutions in several aspects of gastroenterology including CE 7. Until then though, human-based decision-making profoundly impacts patient care and – although not suggested in the updated European Society of Gastrointestinal Endoscopy (ESGE) European curriculum 8 9 – it should be an integral part of CE training. Frequently, interpretation of CE images by experts or at least experienced readers differs. In a tandem CE reading study, expert review of discordant cases revealed a 50 % (13/25 discordant results) error rate by experienced readers, corresponding (in 5/13 cases) to ‘over-classification’ of an irrelevant abnormality 10. Another comparative study showed an ‘over-classification’ of such irrelevant abnormalities in ~10 % of CE readings 11. One thing which has been for a while on the table – in relation to optimizing and/or standardizing CE reporting and subsequent decision-making – is the need for reproducible scoring systems and for a reliable common language among clinicians responsible for further patient’s management.

Over the years, several of these scoring systems were developed while others appear in the wake of software and hardware improvements aiming to replace and/or complement their predecessors. This review presents a comprehensive account of the currently available classification/scoring systems in clinical CE spanning from predicting the bleeding potential of identified SB lesions (with emphasis on vascular lesions), and the individual rebleeding risk; scoring systems for the prediction of SB lesions in patients with obscure gastrointestinal bleeding (OGlB), having the potential to improve patient selection and rationalize the use of enteroscopy, with better allocation of resources, optimized diagnostic workflow and tailored treatment. This review also includes scores for reporting the inflammatory burden, the cleansing level that underscores confidence in CE reporting and the mass or bulge question in CE. Essentially, the aim is to become a main text for reference when scoring is required and facilitate the inclusion of -through readiness of access- one of the other in the final report.

Clinical utility of the small bowel capsule endoscopy in the study of small bowel diseases in Colombia: Results of a national registry

INTRODUCTION

The small bowel capsule endoscopy (SBCE) has revolutionised the study of small bowel diseases. The objective of this study is to determine the indications, findings and diagnostic yield of SBCE in a national registry.

PATIENTS AND METHODS

An observational, analytical cross-sectional study was carried out, analysing the SBCE records at seven centres in the country, where different variables were collected.

RESULTS

1,883 SBCEs were evaluated. The average age was 55.4 years (5.6-94.2). The most frequent indications were suspicion of small bowel bleeding (SBB) (64.4%), study of Crohn's disease (15.2%) and chronic diarrhoea (11.2%). 54.3% were prepared with laxatives. The most frequent lesions found were erosions/ulcers (31.6%), angioectasias (25.7%) and parasitosis (2.7%). The diagnostic yield (P1+P2, Saurin classification) of SBCE in SBB was 60.6%, being higher in overt SBB (66.0%) compared to occult SBB (56.0%) (P=.003). The studies with better preparation showed higher detection of lesions (93.8% vs. 89.4%) (OR=1.8, CI: 95%: 1.2-2.6; P=.004). The SBCE complication rate was 3.1%, with complete SB visualisation at 96.6% and SB retention rate of 0.7%. 81.5% of SBCEs were performed on an outpatient basis, and presented a greater complete SB visualisation than hospital ones (97.1% vs. 94.3%) (OR=2.1, CI: 95%, 1.2-3.5; P=.008).

CONCLUSIONS

The indications, findings and diagnostic performance of SBCEs in Colombia are similar to those reported in the literature, with a high percentage of complete studies and a low rate of complications.

A Gratifying Step forward for the Application of Artificial Intelligence in the Field of Endoscopy: A Narrative Review

Endoscopy is the optimal choice of diagnosis of gastrointestinal (GI) diseases. Following the advancements made in medical technology, different kinds of novel endoscopy-methods have emerged. Although the significant progress in the penetration of endoscopic tools that have markedly improved the diagnostic rate of GI diseases, there are still some limitations, including instability of human diagnostic performance caused by intensive labor burden and high missed diagnosis rate of subtle lesions. Recently, artificial intelligence (AI) has been applied gradually to assist endoscopists in addressing these issues.

Poor Quality of Small Bowel Capsule Endoscopy Images Has a Significant Negative Effect in the Diagnosis of Small Bowel Malignancy

Background and Aims

Capsule endoscopy (CE) is a visual modality; hence, diagnosis relies on image quality. We studied the contribution of image parameters to visualization quality and their effect on diagnostic certainty of small bowel (SB) lesions.

Methods

Five clear CE images of common SB pathology – two vascular lesions, two inflammatory, one polyp – were processed for three image parameters to simulate poor SB conditions: opacity (color-matched to luminal content; 10–90%, 10% increments); blurriness (radius 1–10 pixels; one pixel increments); and contrast (−50-50%; 10% increments). Nine expert readers evaluated whether images were adequate for diagnosis. Points where perception of image quality changed significantly were determined for each parameter. Three further sets of SBCE images (vascular, inflammatory, and neoplastic lesions; nine images/set) were processed for four points/parameters. Twenty experienced/expert CE readers reviewed these images.

Results

The negative effects of opacity in diagnostic certainty were mostly evident in images of neoplasia; images of vascular and inflammatory lesions were less affected. Similar results were observed with increasing blur radius, simulating movement, and poor focus. The proportions of readers finding vascular and inflammatory images adequate for diagnosis did not drop significantly at wider blur radii, while images of neoplasia were quickly deemed inadequate. Low contrast had a greater negative effect than high, most consistently in neoplastic lesions.

Conclusion

Poor visualization quality in all parameters affected mostly neoplastic lesions. Software to increase contrast and sharpen images can improve visualization quality; smart frame rate adaptation could improve the number of high-quality frames obtained. Thoroughness in SB cleansing is most important when there is a suspicion of neoplasia.

Small-bowel capsule endoscopy in patients with celiac disease, axial versus lateral/panoramic view: Results from a prospective randomized trial

BACKGROUND AND AIM

Capsule enteroscopy (CE) is recommended in the management of complicated celiac disease (CD). However, published data are derived from axial-view capsule systems. No data are available on the use of lateral/panoramic view capsules. This study aimed at evaluating the diagnostic yield and efficacy of the lateral/panoramic versus the axial view capsule system in CD.

METHODS

Consecutive CD patients were enrolled in a prospective monocentric study. Each patient ingested an axial (PillCam SB3) and a lateral/panoramic (CapsoCam Plus) view capsule with a 3-h interval in a randomized order. Two experts blindly evaluated the CE carried out. A third expert reviewed the videos in cases of discordance.

RESULTS

Twenty-five CD patients were enrolled (four males, age at CE 51.2 ± 16.6 years, age at CD diagnosis 41.7 ± 20.6, years on a gluten-free diet [GFD] 9.6 ± 9.4). Indications at CE were refractory CD in nine cases, non-responsiveness to GFD in 10 and GFD non-compliance in six. A positive finding was evidenced in 15 (60%) and 13 (52%) cases by CapsoCam and PillCam respectively (not significant). Atrophy was detected by both capsules. Considering the percentage of the small-bowel mucosa presenting atrophy signs, mean values were 22% ± 35 and 20% ± 29 for lateral/panoramic and axial systems, respectively (not significant). Compared to duodenal histology, PillCam correctly identified 80% of patients with SB atrophy, whereas CapsoCam identified 73% of cases.

CONCLUSIONS

Lateral/panoramic view CE is effective in the detection of small-bowel atrophy in CD and presents good sensitivity and specificity when compared to histology.

Usefulness of panoramic 344°-viewing in Crohn's disease capsule endoscopy: a proof of concept pilot study with the novel PillCam™ Crohn's system

BACKGROUND

A new capsule endoscopy (CE) system featuring two advanced optics for 344°-viewing and a prolonged operative time has been recently developed for Crohn's disease (CD) patients. Hence, we evaluated, for the first time, the performance of this novel CE and the add-on value of the 344°-viewing in a multi-center real-life setting.

METHODS

Consecutive patients with suspected or established CD received the PillCam™ Crohn's System as supplementary diagnostic work-up focused on the small-bowel between June 2017 and June 2018. Technical and clinical data, including the panenteric CE diagnostic yield, the Lewis score and the impact of small-bowel findings on clinical management during a 6-months follow-up (new diagnosis, staging or treatment upgrade) were collected, thereby evaluating the added value of the 344° panoramic-view (lesions detected by camera A and B) over the standard 172°-view (lesions detected by one camera only).

RESULTS

Among 41 patients (aged 43 ± 20 years), 73% underwent CE for suspected CD and 27% for established CD. The rate of complete enteroscopy was 90%. No technical failure or retention occurred. Compared to the standard 172° view, the panoramic 344°-view revealed a greater number of patients with a relevant lesion (56.1% vs. 39.0%; P = 0.023), resulting in higher Lewis score (222,8 vs. 185.7; P = 0.031), and improved clinical management (48.8% vs. 31.7%, P = 0.023).

CONCLUSIONS

The panoramic 344°-view increases small-bowel CE accuracy, thereby improving the clinical management of CD patients with mild small-bowel active disease. This system should be regarded as a new standard for both small-bowel diagnosis and monitoring in inflammatory bowel diseases.

CAD-CAP: a 25,000-image database serving the development of artificial intelligence for capsule endoscopy

Background and study aims  Capsule endoscopy (CE) is the preferred method for small bowel (SB) exploration. With a mean number of 50,000 SB frames per video, SBCE reading is time-consuming and tedious (30 to 60 minutes per video). We describe a large, multicenter database named CAD-CAP (Computer-Assisted Diagnosis for CAPsule Endoscopy, CAD-CAP). This database aims to serve the development of CAD tools for CE reading. Materials and methods  Twelve French endoscopy centers were involved. All available third-generation SB-CE videos (Pillcam, Medtronic) were retrospectively selected from these centers and deidentified. Any pathological frame was extracted and included in the database. Manual segmentation of findings within these frames was performed by two pre-med students trained and supervised by an expert reader. All frames were then classified by type and clinical relevance by a panel of three expert readers. An automated extraction process was also developed to create a dataset of normal, proofread, control images from normal, complete, SB-CE videos. Results  Four-thousand-one-hundred-and-seventy-four SB-CE were included. Of them, 1,480 videos (35 %) containing at least one pathological finding were selected. Findings from 5,184 frames (with their short video sequences) were extracted and delimited: 718 frames with fresh blood, 3,097 frames with vascular lesions, and 1,369 frames with inflammatory and ulcerative lesions. Twenty-thousand normal frames were extracted from 206 SB-CE normal videos. CAD-CAP has already been used for development of automated tools for angiectasia detection and also for two international challenges on medical computerized analysis.

Nomenclature and semantic descriptions of ulcerative and inflammatory lesions seen in Crohn's disease in small bowel capsule endoscopy: An international Delphi consensus statement

BACKGROUND

In the medical literature, the nomenclature and descriptions (ND) of small bowel (SB) ulcerative and inflammatory (U-I) lesions in capsule endoscopy (CE) are scarce and inconsistent. Inter-observer variability in interpreting these findings remains a major limitation in the assessment of the severity of mucosal lesions, which can impact negatively on clinical care, training and research on SB-CE.

OBJECTIVE

Focusing on SB-CE in Crohn's disease (CD), our aim is to establish a consensus on the ND of U-I lesions.

METHODS

An international panel of experienced SB-CE readers was formed during the 2016 United European Gastroenterology Week meeting. A core group of five CE and inflammatory bowel disease (IBD) experts established an Internet-based, three-round Delphi consensus but did not participate in the voting process. The core group built illustrated questionnaires, including SB-CE still frames of U-I lesions from patients with documented CD. Twenty-seven other experts were asked to rate and comment on the different proposals for the ND of the most frequent SB U-I lesions. For each round, we used a 6-point rating scale (varying from 'strongly disagree' to 'strongly agree'). The consensus was reached when at least 80 % of the voting members scored the statement within the 'agree' or 'strongly agree' categories.

RESULTS

A 100% participation rate was obtained for all the rounds. Consensual ND were reached for the following seven U-I lesions: aphthoid erosion, deep ulceration, superficial ulceration, stenosis, edema, hyperemia and denudation.

CONCLUSION

Considering the most frequent SB U-I lesions seen in CE in CD, a consensual ND was reached by the international group of experts. These descriptions and names are useful not only for daily practice and medical education, but also for medical research.

Endoscopic ultrasonography and small-bowel endoscopy: Present and future

Over the last decade, impressive technological advances have occurred in ultrasonography and small-bowel endoscopy. Nowadays, endoscopic ultrasonography is an essential diagnostic tool and a therapeutic weapon for pancreatobiliary disorders. Capsule endoscopy and device-assisted enteroscopy have quickly become the reference standard for the diagnosis of small-bowel luminal diseases, thereby leading to radical changes in diagnostic and therapeutic pathways. We herein provide an up-to-date overview of the latest advances in endoscopic ultrasonography and small-bowel endoscopy, focusing on the emerging paradigms and technological innovations that might improve clinical practice in the near future.