Bowel preparations for capsule endoscopy: a comparison between simethicone and magnesium citrate

Capsule endoscopy for small bowel bleed: Current update

Small intestine, hitherto an obscure area for endoscopists before 2000, is now easily evaluated non-invasively using capsule endoscopy and invasively by device-assisted enteroscopies. Major advances in understanding the causes and management of small bowel diseases have been in obscure gastrointestinal (GI) bleed, currently re-named as small bowel bleed, after the discovery of capsule endoscopy. The current article is a narrative review of the technology of capsule endoscopy, its advantages and limitations, future perspective and Indian studies on its utility in patients with small bowel bleed. Till date, eight large series reporting 2319 patients with obscure GI bleed (1554 overt and 765 occult) undergoing capsule endoscopy have been reported from India. Overall yield of capsule endoscopy to detect lesions in these studies varied from 43.5% to 90%. The major causes detected in various studies for small bowel bleed include vascular malformation, portal hypertensive enteropathy, ulcer, stricture, tumor, polyps, etc. Hookworm can cause both occult as well as overt small bowel bleed as shown mainly from India. Capsule endoscopy has also been quite safe in patients with small bowel bleed as despite 0.6% to 15% retention of imaging capsule in Indian studies, development of clinically evident small bowel obstruction has rarely been reported. The major limitations of capsule endoscopy include lack of maneuvrability and therapeutic capability. Research is in progress to overcome some of the limitations of the current capsule endoscopy system. It is concluded that discovery of capsule endoscopy has brought a new paradigm in GI endoscopy and explored a hitherto unexplored area of GI tract, i.e. small bowel that continued to be a black box for the endoscopists.

Optimal Bowel Preparation Method to Visualize the Distal Ileum via Small Bowel Capsule Endoscopy

Small bowel capsule endoscopy (SBCE) is a convenient and minimally invasive method widely used to evaluate the small intestine. However, especially in the distal ileum, visualization of the intestinal mucosa is frequently hampered by the remaining intestinal contents, making it difficult to detect critical lesions. Although several studies have reported on the efficacy of bowel preparation before SBCE, no standardized protocol has been established. Herein, we determined the optimal preparation method for better visualization of the distal ileum using SBCE. We retrospectively analyzed 259 consecutive patients who had undergone SBCE between July 2009 and December 2019, divided into three groups: Group A (no preparation except overnight fasting), Group B (ingestion of 1-2 L polyethylene glycol 4 h before colonoscopy after overnight fasting and performing SBCE immediately after colonoscopy), and Group C (ingestion of 0.9 L magnesium citrate [MC] before SBCE after overnight fasting). The visibility of the intestinal mucosa in the first 10 min and at the last 10 min during the period of observation of the distal ileum was examined using a scoring system and compared. The visibility of the images captured by SBCE was assessed based on the scoring of the degree of bile/chyme staining, residual fluid and debris, brightness, bubble reduction, and visualized mucosa. The status of intestinal collapse was also assessed. In the first 10 min of observation of the distal ileum, no significant differences were detected among the groups. In the last 10 min, significantly better images were acquired in Group C in terms of bile/chyme staining, brightness, bubble reduction, and visualized mucosa. Bowel preparation using a low-dose MC solution 2 h before SBCE provided significantly higher-quality images of the distal ileum. Further optimization, such as the timing of initiating the preparation, is necessary to determine the optimal regimen for bowel preparation prior to SBCE.

Inter/Intra-Observer Agreement in Video-Capsule Endoscopy: Are We Getting It All Wrong? A Systematic Review and Meta-Analysis

Video-capsule endoscopy (VCE) reading is a time- and energy-consuming task. Agreement on findings between readers (either different or the same) is a crucial point for increasing performance and providing valid reports. The aim of this systematic review with meta-analysis is to provide an evaluation of inter/intra-observer agreement in VCE reading. A systematic literature search in PubMed, Embase and Web of Science was performed throughout September 2022. The degree of observer agreement, expressed with different test statistics, was extracted. As different statistics are not directly comparable, our analyses were stratified by type of test statistics, dividing them in groups of "None/Poor/Minimal", "Moderate/Weak/Fair", "Good/Excellent/Strong" and "Perfect/Almost perfect" to report the proportions of each. In total, 60 studies were included in the analysis, with a total of 579 comparisons. The quality of included studies, assessed with the MINORS score, was sufficient in 52/60 studies. The most common test statistics were the Kappa statistics for categorical outcomes (424 comparisons) and the intra-class correlation coefficient (ICC) for continuous outcomes (73 comparisons). In the overall comparison of inter-observer agreement, only 23% were evaluated as "good" or "perfect"; for intra-observer agreement, this was the case in 36%. Sources of heterogeneity (high, I2 81.8-98.1%) were investigated with meta-regressions, showing a possible role of country, capsule type and year of publication in Kappa inter-observer agreement. VCE reading suffers from substantial heterogeneity and sub-optimal agreement in both inter- and intra-observer evaluation. Artificial-intelligence-based tools and the adoption of a unified terminology may progressively enhance levels of agreement in VCE reading.

Development and Verification of a Deep Learning Algorithm to Evaluate Small-Bowel Preparation Quality

Capsule endoscopy (CE) quality control requires an objective scoring system to evaluate the preparation of the small bowel (SB). We propose a deep learning algorithm to calculate SB cleansing scores and verify the algorithm’s performance. A 5-point scoring system based on clarity of mucosal visualization was used to develop the deep learning algorithm (400,000 frames; 280,000 for training and 120,000 for testing). External validation was performed using additional CE cases (n = 50), and average cleansing scores (1.0 to 5.0) calculated using the algorithm were compared to clinical grades (A to C) assigned by clinicians. Test results obtained using 120,000 frames exhibited 93% accuracy. The separate CE case exhibited substantial agreement between the deep learning algorithm scores and clinicians’ assessments (Cohen’s kappa: 0.672). In the external validation, the cleansing score decreased with worsening clinical grade (scores of 3.9, 3.2, and 2.5 for grades A, B, and C, respectively, p < 0.001). Receiver operating characteristic curve analysis revealed that a cleansing score cut-off of 2.95 indicated clinically adequate preparation. This algorithm provides an objective and automated cleansing score for evaluating SB preparation for CE. The results of this study will serve as clinical evidence supporting the practical use of deep learning algorithms for evaluating SB preparation quality.

Preparation, Timing, Prokinetics, and Surface Agents in Video Capsule Endoscopy

There is a trend in data to support active preparation for video capsule endoscopy (VCE), but the timing of this remains unclear. Split dosing may be the most efficacious preparation. Study methodology continues to evolve, with increased use of standardized scales, with the addition of diagnostic yield as an outcome. The use of adjuncts has not been detrimental, but their value has not been proved to improve outcomes of VCE.

Development of a deep learning-based software for calculating cleansing score in small bowel capsule endoscopy

A standardized small bowel (SB) cleansing scale is currently not available. The aim of this study was to develop an automated calculation software for SB cleansing score using deep learning. Consecutively performed capsule endoscopy cases were enrolled from three hospitals. A 5-step scoring system based on mucosal visibility was trained for deep learning in the training set. Performance of the trained software was evaluated in the validation set. Average cleansing score (1.0 to 5.0) by deep learning was compared to clinical grading (A to C) reviewed by clinicians. Cleansing scores decreased as clinical grading worsened (scores of 4.1, 3.5, and 2.9 for grades A, B, and C, respectively, P < 0.001). Adequate preparation was achieved for 91.7% of validation cases. The average cleansing score was significantly different between adequate and inadequate group (4.0 vs. 2.9, P < 0.001). ROC curve analysis revealed that a cut-off value of cleansing score at 3.25 had an AUC of 0.977. Diagnostic yields for small, hard-to-find lesions were associated with high cleansing scores (4.3 vs. 3.8, P < 0.001). We developed a novel scoring software which calculates objective, automated cleansing scores for SB preparation. The cut-off value we suggested provides a standard criterion for adequate bowel preparation as a quality indicator.

KODA score: an updated and validated bowel preparation scale for patients undergoing small bowel capsule endoscopy

Background and study aims  A reliable outcome measure is needed for bowel preparation quality during capsule endoscopy. Currently, no scales are adequately validated. Our objective was to update an existing small bowel preparation score, create a standardized training module, then determine its inter-rater and intra-rater reliability. Patients and methods  Modification to produce standardized scoring of an existing small bowel preparation score was performed followed by development of a training module and validation to create the new Korea-Canada (KODA) score. Twenty readers from a range of backgrounds, including capsule endoscopists, gastroenterology fellows, residents, medical students, and nurses rated bowel cleanliness in 25 capsule videos consisting of 1,233 images, in duplicate 4 weeks apart, after completing the training module. Sequential images selected in 5-minute intervals during small bowel transit were rated on a scale between 0-3 based on the amount of visualized mucosa and the degree of obstruction. Reliability was assessed using estimates of intraclass correlation coefficients (ICCs). Results  Intraclass correlation coefficients for inter-rater (ICC 0.81, 95 % CI 0.70-0.87) and intra-rater (ICC 0.92, 95 % CI 0.87-0.94) reliability were almost perfect among the 20 readers. Inter-rater reliability ranged between 0.72 (95 % CI 0.57-0.81) and 0.89 (95 % CI 0.79-0.93) for nurses and residents, respectively. Intra-rater reliability was greater than 0.90 for all groups except for nurses, which was still almost perfect (ICC 0.86, 95 % CI 0.79-0.90). Conclusions  Almost perfect inter-rater and intra-rater reliability was observed for the KODA score. This simple score could be used for future clinical trials after completion of the training module.

Current Controversies Concerning Capsule Endoscopy

Video capsule endoscopy became a reality in 2001. This device enabled us to directly view the mucosa of the small intestine for the first time. The main indications for the video capsule remain the detection of small intestinal bleeding and iron deficiency anemia, diagnosis and management of Crohn's disease, and detection of tumors. The device is extraordinarily safe and can be used in the very young to the very old. However, there remain several areas of controversy and difficulty. These are covered in this article and include details of indications and contraindications, whether to prepare patients, whether or not to use simethicone and prokinetics. Detection of location of the capsule remains a major engineering challenge. Reading the videos reliably and quickly remains challenging. However, artificial intelligence and machine learning are already on the horizon to provide assistance. New uses for capsule endoscopy promise more accurate diagnosis and hence improved management of acute gastrointestinal bleeding. The colon capsule may eventually help those who refuse conventional colonoscopy, and robotically controlled capsules may be helpful in screening for serious disease in patients with upper abdominal complaints. The advent of the broadening use of video capsule endoscopy is, though it will be controversial, embraced by some and derided by others; such is the nature of technological development. In the long run, if the use of the video capsule, based on sound evidence-based studies, can be shown to improve the care of our patients and reduce the cost of health care, its use will continue to expand.

Capsule endoscopy for small-intestinal disorders: Current status

Small-bowel capsule endoscopy (SBCE) is used widely because of its non-invasive and patient-friendly nature. SBCE can visualize entire small-intestinal mucosa and facilitate detection of small-intestinal abnormalities. In this review article, we focus on the current status of SBCE. Several platforms for SBCE are available worldwide. Third-generation SBCE (PillCam^® SB3) has a high-resolution camera equipped with an adaptive frame rate system. Several software modes have been developed to reduce the reading time for capsule endoscopy and to minimize the possibility of missing lesions. The main complication of SBCE is capsule retention. Thus, the main contraindication for SBCE is known or suspected gastrointestinal obstruction unless intestinal patency is proven. Possible indications for SBCE are obscure gastrointestinal bleeding, Crohn's disease, small-intestinal polyps and tumors, and celiac disease. Colon capsule endoscopy (CCE) can observe inflamed colonic mucosa non-invasively, and allows for the continuous and non-invasive observation of the entire intestinal tract (pan-endoscopy). Recently, application of CCE as pan-enteric endoscopy for inflammatory bowel diseases (including Crohn's disease) has been reported. In the near future, reading for CE will be assisted by artificial intelligence, and reading CE videos for long periods will not be required.

Performance measures for small-bowel endoscopy: A European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) together with the United European Gastroenterology (UEG) recently developed a short list of performance measures for small-bowel endoscopy (i.e. small-bowel capsule endoscopy and device-assisted enteroscopy) with the final goal of providing endoscopy services across Europe with a tool for quality improvement. Six key performance measures both for small-bowel capsule endoscopy and for device-assisted enteroscopy were selected for inclusion, with the intention being that practice at both a service and endoscopist level should be evaluated against them. Other performance measures were considered to be less relevant, based on an assessment of their overall importance, scientific acceptability, and feasibility. Unlike lower and upper gastrointestinal endoscopy, for which performance measures had already been identified, this is the first time small-bowel endoscopy quality measures have been proposed.

Repetitive Position Change Improves Gastric Cleanliness for Magnetically Controlled Capsule Gastroscopy

BACKGROUND AND AIMS

Good gastric preparation is essential for magnetically controlled capsule gastroscopy (MCCG) examination. This study aims to determine if repetitive position change after dimethicone premedication could further improve gastric cleanliness for MCCG.

METHODS

Consecutive patients referred for MCCG in our center from May 7 to May 31, 2018 were prospectively enrolled and randomized to undergo repetitive position change for 15 min (position change group) or not (conventional group) after ingesting dimethicone. Primary outcome was gastric cleanliness score and secondary outcomes were detection rate of positive findings, number of lesions per patient, gastric examination time, and safety of MCCG.

RESULTS

Totals of 43 and 40 were included in the position change and conventional groups, respectively. Gastric cleanliness score in the position change group was significantly higher than in the conventional group (21.2 ± 1.0 vs. 18.6 ± 2.0, P  < 0.001), as was the proportion of acceptable gastric cleanliness (gastric cleanliness score ≥ 18) (100% vs. 72.5%, P  < 0.001). There was no statistical difference in detection rate of positive findings between the two groups (27.9% vs. 27.5%, P  = 0.97). In the position change group, the gastric examination time was significantly reduced (13.2 ± 4.0 vs. 15.3 ± 5.1, P = 0.043). No adverse events were observed.

CONCLUSIONS

Repetitive position change after dimethicone premedication significantly improves gastric cleanliness for MCCG examination. Clinical Trial Registration ClinicalTrials.gov, ID: NCT03514966.

Gastric preparation for magnetically controlled capsule endoscopy: A prospective, randomized single-blinded controlled trial

BACKGROUND AND AIMS

Magnetically controlled capsule endoscopy (MCE) is a novel technique for which there is no agreed gastric preparation. We aimed to determine an optimal standardized gastric preparation regimen.

METHODS

120 patients referred for MCE were randomly assigned to gastric preparation with either water alone (A), water with simethicone (B) or water, simethicone and pronase (C). Image quality was assessed using cleanliness and visualization scores, higher scores equating to better image quality.

RESULTS

The total cleanliness scores were (mean±SD) 15.83±2.41 (A), 21.35±1.23 (B), and 20.82±1.90 (C). The total visualization scores (mean±SD) were 10.75±2.02 (A), 15.20±1.32 (B), and 15.08±1.86 (C). While the image quality of the whole stomach in groups B and C were significantly better than group A (P<0.0001), there was no statistical difference between group B and C (P>0.05). MCE detected positive findings in 21 (52.5%), 27 (67.5%) and 21 (53.8%) patients in group A, B and C respectively, with no significant difference between groups (P>0.5).

CONCLUSIONS

Simethicone swallowed with water prior to MCE produced the optimal gastric mucosal image quality. The addition of pronase had no demonstrable additional benefit.

Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?

INTRODUCTION

Optimal bowel preparation for small bowel capsule endoscopy(SBCE) is controversial. This meta-analysis aimed to investigate the effects of laxatives in SBCE.

METHODS

A comprehensive literature search was conducted for studies investigating the use of laxatives in SBCE. The primary outcome was diagnostic yield(DY) for SB findings; secondary outcomes SB visualization quality(SBVQ) and completion rate(CR). Pooled odds ratios(ORs) with 95% confidence intervals(CIs) and number needed to treat(NNT) were calculated.

RESULTS

Forty studies (4380 patients with laxatives, 2185 without) were included. Laxative use did not improve DY of SB findings overall (OR 1.11 (95%CI 0.85-1.44)) or for significant SB findings (OR 1.10 (95%CI 0.76-1.60)). However, SBVQ improved with the use of laxatives (OR 1.60 (95%CI 1.08-2.06)), NNT 14. The OR for completed SBCE was 1.30 (95%CI 0.95-1.78). Patients given polyethylene glycol(PEG) had lower DY than sodium phosphate(NaP). SBVQ improved more with NaP (NNT 7) than PEG (NNT 53).

CONCLUSIONS

Laxatives do not significantly improve DY or CR in SBCE, but do improve SBQV. The use of laxatives may be beneficial in patients likely to have subtle findings. There are significant differences in methodology/definitions between studies, hence the need for standardized visualization scoring and recording of SBCE findings.

Small-bowel capsule endoscopy with panoramic view: results of the first multicenter, observational study (with videos)

BACKGROUND AND AIMS

The first small-bowel video-capsule endoscopy (VCE) with 360° panoramic view has been developed recently. This new capsule has wire-free technology, 4 high-frame-rate cameras, and a long-lasting battery life. The aim of the present study was to assess the performance and safety profile of the 360° panoramic-view capsule in a large series of patients from a multicenter clinical practice setting.

METHODS

Consecutive patients undergoing a 360° panoramic-view capsule procedure in 7 European Institutions between January 2011 and November 2015 were included. Both technical (ie, technical failures, completion rate) and clinical (ie, indication, findings, retention rate) data were collected by means of a structured questionnaire. VCE findings were classified according to the likelihood of explaining the reason for referral: P0, low; P1, intermediate; P2, high.

RESULTS

Of the 172 patients (94 men; median age, 68 years; interquartile range, 53-75), 142 underwent VCE for obscure (32 overt, 110 occult) GI bleeding (OGIB), and 28 for suspected (17) or established (2) Crohn's disease (CD). Overall, 560 findings were detected; 252 were classified as P2. The overall diagnostic yield was 40.1%; 42.2% and 30.0% in patients with OGIB and CD, respectively. The rate of complete enteroscopy was 90.2%. All patients but one, who experienced capsule retention (1/172, 0.6%), excreted and retrieved the capsule. VCE failure occurred in 4 of 172 (2.3%) patients because of technical problems.

CONCLUSIONS

This multicenter study, conducted in the clinical practice setting and based on a large consecutive series of patients, showed that the diagnostic yield and safety profile of the 360° panoramic-view capsule are similar to those of forward-view VCEs.

Neoplastic Diseases of the Small Bowel

The incidence of small bowel tumors is increasing over time. Until recently, their diagnosis was delayed and it was often reached only at the time of surgery. New diagnostic tools, such as capsule endoscopy, device-assisted enteroscopy, and dedicated small bowel cross-sectional imaging techniques, have been introduced recently in clinical practice. The combination of these tools allows medical practitioners to detect small bowel tumors at an early stage and to reach a definite diagnosis before surgery, thus enabling minimally invasive treatments.

Review of small-bowel cleansing scales in capsule endoscopy: A panoply of choices

Evaluation of the quality of small-bowel cleansing is required to assess the reliability of findings in capsule endoscopy (CE). Moreover, consensus regarding the need of intestinal preparation for CE remains to be achieved. The presence of multiple grading scales for small-bowel preparation in CE, which are time-consuming and complicated, adds difficulty to the comparison of different small-bowel cleansing regimens and their application in clinical practice. Nowadays, a validated scale universally accepted for grading small-bowel cleansing is lacking. In fact, there are numerous grading systems with very different technical characteristics, namely, the parameters and the portion of the CE video that are analyzed, the objectivity of the analysis, the lesser or greater dependency on the operator, and the validation of the score. The authors performed a review which aims to systematize and summarize currently available small-bowel grading scales in CE.

Superiority of the Split-dose PEG Regimen for Small-Bowel Capsule Endoscopy: A Randomized Controlled Trial

GOALS

We aimed to evaluate the small-bowel cleansing quality, the diagnostic yield (DY), the transit time, and the patients' tolerability, by comparing the 2 different polyethylene glycol (PEG) administration schedules.

BACKGROUND

The use of bowel purgatives before small-bowel capsule endoscopy (SBCE) is recommended by the ESGE guidelines. Whether this regimen can be further refined by changing the timing of administration is unknown.

STUDY

Fifty-seven patients were prospectively enrolled and randomized into 2 groups: group 1 (G1, n=29) received 2 L of PEG in the day before SBCE (time between PEG and SBCE=10 h); and group 2 (G2, n=28) received 1 L of PEG in the day before SBCE and 1 L of PEG in the morning before SBCE (time between PEG and SBCE=4 h). The primary outcome measure was small-bowel cleansing quality. Small-bowel cleansing quality was evaluated according to a previously validated grading scale.

RESULTS

The entire and distal half small-bowel cleansing scores were significantly higher among G2 (median score: 8 vs. 10 points, P=0.012; median score: 6 vs. 8 points, P=0.05, respectively). The DY did not differ significantly between groups. There were no significant differences in transit times between the 2 PEG regimens. Both schedules were well tolerated, showing no differences regarding symptoms while ingesting the preparation or after SBCE ingestion.

CONCLUSIONS

Split-dose PEG regimen for SBCE preparation improved the small-bowel cleanliness, did not interfere with transit times and was equally well tolerated by the patients. No differences were observed regarding DY. ClinicalTrial.gov registration: NCT02396017.

Low volume polyethylene glycol with ascorbic acid, sodium picosulfate-magnesium citrate, and clear liquid diet alone prior to small bowel capsule endoscopy

AIM: To compare low volume polyethylene glycol with ascorbic acid, sodium picosulfate-magnesium citrate and clear liquid diet alone as bowel preparation prior to small bowel capsule endoscopy (CE).

METHODS: We retrospectively collected all CE studies done from December 2011 to July 2013 at a single institution. CE studies were reviewed only if low volume polyethylene glycol with ascorbic acid, sodium picosulfate-magnesium citrate or clear liquid diet alone used as the bowel preparation. The studies were then reviewed by the CE readers who were blinded to the preparation type. Cleanliness and bubble burden were graded independently within the proximal, middle and distal small bowel using a four-point scale according to the percentage of small bowel mucosa free of debris/bubbles: grade 1 = over 90%, grade 2 = between 90%-75%, grade 3 = between 50%-75%, grade 4 = less than 50%. Data are expressed as mean ± SEM. ANOVA and Fishers exact test were used where appropriate. P values < 0.05 were considered statistically significant.

RESULTS: A of total of 123 CE studies were reviewed. Twenty-six studies were excluded from analysis because of incomplete small bowel examination. In the remaining studies, 39 patients took low volume polyethylene glycol with ascorbic acid, 31 took sodium picosulfate-magnesium citrate and 27 took a clear liquid diet alone after lunch on the day before CE, followed by overnight fasting in all groups. There was no significant difference in small bowel cleanliness (1.98 ± 0.09 vs 1.84 ± 0.08 vs 1.76 ± 0.08) or small bowel transit time (213 ± 13 vs 248 ± 14 ± 225 ± 19 min) for clear liquid diet alone, MoviPrep and Pico-Salax respectively. The bubble burden in the mid small bowel was significantly higher in the MoviPrep group (1.6 ± 0.1 vs 1.9 ± 0.1 vs 1.6 ± 0.1, P < 0.05). However this did not result in a significant difference in diagnosis of pathology.

CONCLUSION: There was no significant difference in small bowel cleanliness or diagnostic yield of small bowel CE between the three preparations regimens used in this study.

Video capsule endoscopy: is bowel preparation necessary?

There is no standardized protocol for bowel preparation prior to video capsule endoscopy, although one is strongly recommended. The purpose of our study was to see if there was a statistical significance between small bowel mucosal visualization rates for those who received bowel preparation and those who did not. We retrospectively analyzed all patients who had a video capsule endoscopy from August 2014 to January 2016 at a tertiary care center. All patients fasted prior to the procedure. Bowel preparation when used consisted of polyethylene glycol. A long fast consisted of 12 or more hours. The grading system used to assess the small bowel was adapted from a previously validated system from Esaki et al. Statistical analyses were performed using Fisher's exact test or Welch's 2-sample t-test and statistical significance was present if the p value was ≤0.05. 76 patients were carried forward for analysis. Small bowel mucosal visualization rates were similar between those who received bowel preparation and those who did not (92.5% vs 88.9%, p=0.44). Small bowel mucosal visualization rates were significantly better in those patients who had a long fast compared with those who had a short fast (97.7% vs 81.3%, p=0.019). Our study demonstrates that the addition of bowel preparation prior to video capsule endoscopy does not significantly improve small bowel mucosal visualization rates and, in addition, there is a statistically significant relationship between increased fasting time and improved small bowel mucosal visualization. A prolonged fast without bowel preparation might be satisfactory for an adequate small bowel visualization but further randomized, prospective studies are necessary to confirm these findings.

A Single-Center Randomized Controlled Trial Evaluating Timing of Preparation for Capsule Enteroscopy

Background/Aims

Intestinal lavage (IL) administration immediately before capsule enteroscopy (CE) is superior to lavage the day before the procedure. We aimed to determine the effect of IL timing on CE diagnostic yield.

Methods

Patients referred for CE were randomized prospectively into two equal groups according to the timing of IL with 2 L of polyethylene glycol solution. Group A and B underwent IL over 2 hours beginning 14 and 4 hours, respectively, before the scheduled CE. The primary outcome measure was preparation quality, measured with a predetermined validated grading scale.

Results

A total of 34 patients were randomized. The frequency of mucosal abnormalities (77% vs. 82%, p=not significant [NS]) and diagnostic yield (47% vs. 53%, p=NS) were similar between the two groups. Moreover, no significant association between the quality of small bowel preparation and the timing at which the purgative for IL was administered was observed (overall fluid transparency, p=0.936; overall mucosal invisibility, p=0.091).

Conclusions

Day-before IL is equivalent to same-day IL in terms of overall preparation quality, proportion of complete studies to cecum, small bowel transit time, frequency of identified mucosal abnormalities, and overall diagnostic yield.

Analysis of a grading system to assess the quality of small-bowel preparation for capsule endoscopy: in search of the Holy Grail

BACKGROUND

The diagnostic yield of capsule endoscopy is vulnerable to inadequate visualization related to residual bile or chyme remaining in the lumen despite intestinal lavage. It has been challenging to determine the optimal lavage preparation of the bowel and patient diet before capsule endoscopy, as well as the timing of the procedure, because no well-accepted, validated grading system for assessing the quality of intestinal lavage before capsule endoscopy is available. There remains no consensus on the reliability of qualitative, quantitative, or computer-derived assessments of the quality of preparation for capsule endoscopy. This study evaluates intra-observer and interobserver agreement for a previously validated scale.

MATERIALS AND METHODS

The digital images of 34 patients who underwent capsule endoscopy were independently reviewed by two blinded physicians according to a previously validated grading scale. One of the physicians reviewed and graded the patients a second time. The quality of the bowel luminal preparation was assessed with a qualitative parameter (fluid transparency) and a more quantitative parameter (mucosal invisibility) for each of three small-intestinal segments, and an overall small-bowel score for each parameter was assigned as well. A weighted kappa coefficient was used to calculate intra-observer (observer 1A and 1B) and interobserver (observer 1A and observer 2) agreement. A kappa value of 0.60 or more suggests strong agreement, 0.40 to 0.60 moderate agreement, and less than 0.40 poor agreement.

RESULTS

The intra-observer weighted kappa index for both fluid transparency and mucosal visibility was 0.52, which is consistent with moderate agreement. The interobserver weighted kappa indices for fluid transparency and mucosal invisibility were 0.29 and 0.42, respectively, demonstrating suboptimal interobserver agreement. The individual segment interobserver kappa indices were better for mucosal visibility (0.52, 0.39, and 0.47 for small-bowel segments 1, 2, and 3, respectively) than for fluid transparency (0.18, 0.38, and 0.31).

CONCLUSIONS

The proposed grading scale for assessing the quality of preparation for capsule endoscopy has inadequate interobserver and intra-observer agreement. Capsule endoscopy preparation grading scales that focus more on quantitative than on qualitative assessment may demonstrate more reliable performance characteristics. Optimizing the quality of preparation and diagnostic yield of capsule endoscopy will first require the development of a well-validated grading scale.

Coffee enema for preparation for small bowel video capsule endoscopy: a pilot study

Coffee enemas are believed to cause dilatation of bile ducts and excretion of bile through the colon wall. Proponents of coffee enemas claim that the cafestol palmitate in coffee enhances the activity of glutathione S-transferase, an enzyme that stimulates bile excretion. During video capsule endoscopy (VCE), excreted bile is one of the causes of poor preparation of the small bowel. This study aimed to evaluate the feasibility and effect of coffee enema for preparation of the small bowel during VCE. In this pilot study, 17 of 34 patients were assigned to the coffee enema plus polyethylene glycol (PEG) 2 L ingestion group, whereas the 17 remaining control patients received 2 L of PEG only. The quality of bowel preparation was evaluated in the two patient groups. Bowel preparations in the proximal segments of small bowel were not differ between two groups. In the mid and distal segments of the small intestine, bowel preparations tend to be better in patients who received coffee enemas plus PEG than in patients who received PEG only. The coffee enema group did not experience any complications or side effects. Coffee enemas may be a feasible option, and there were no clinically significant adverse events related to coffee enemas. More prospective randomized studies are warranted to improve small bowel preparation for VCE.

Consensus guidelines for the use of bowel preparation prior to colonic diagnostic procedures: colonoscopy and small bowel video capsule endoscopy

BACKGROUND

Adequate bowel preparation prior to colonic diagnostic procedures is essential to ensure adequate visualisation.

SCOPE

This consensus aims to provide guidance as to the appropriate use of bowel preparation for a range of defined clinical circumstances. A consensus group from across Europe was convened and met to discuss appropriate bowel preparation. The use of polyethylene glycol (PEG), sodium picosulphate and sodium phosphate (NaP), together with other agents, prokinetics and simethicone, in colonoscopy and small bowel video capsule endoscopy were considered. A systematic review of the literature was carried out and additional unpublished data was obtained from the members of the consensus group where required. Recommendations were graded according to the level of evidence.

FINDINGS

PEG-based regimens are recommended first line for both procedures, since their use is supported by good efficacy and safety data. Sodium-picosulphate-based regimens are recommended second line as their cleansing efficacy appears less than PEG-based regimens. NaP is not recommended for bowel cleansing due to the potential for renal damage and other adverse events. However, the use of NaP is acceptable in patients in whom PEG or sodium picosulphate is ineffective or not tolerated. NaP should not be used in patients with chronic kidney disease, pre-existing electrolyte disturbances, congestive heart failure, cirrhosis or a history of hypertension. The timing of the dose, dietary restrictions, use in special patient groups and recording of the quality of bowel preparation are also considered for patients undergoing colonoscopy. During the development of the guidelines the European Society of Gastrointestinal Endoscopy (ESGE) issued guidance on bowel preparation for colonoscopy. The ESGE guidelines and these consensus guidelines share many recommendations; differences between the guidelines are reviewed.

CONCLUSION

The use of bowel preparation should be tailored to the individual patient and their specific clinical circumstances.

Premedication with N-acetylcysteine and simethicone improves mucosal visualization during gastroscopy: a randomized, controlled, endoscopist-blinded study

OBJECTIVES

Diagnostic gastroscopy provides a unique opportunity to diagnose early oesophagogastric neoplasia; however, intraluminal mucus and bile can obscure mucosal visualization. The aim of this study was to determine whether the use of a premedication solution containing the mucolytic agent N-acetylcysteine and the surfactant simethicone improves mucosal visualization within a UK diagnostic gastroscopy service.

MATERIALS AND METHODS

A total of 75 consecutive patients were recruited from a single (S.J.) endoscopist's diagnostic gastroscopy list. They were randomized into three treatment groups: (a) standard control=clear fluids only for 6 h, nil by mouth for 2 h; (b) water control=standard control+100 ml sterile water (given 20 min before gastroscopy); and (c) solution=standard control+100 ml investigated solution (20 min before gastroscopy). The endoscopist was blinded to patient preparation. Inadequate mucosal visualization was defined as fluid/mucus during gastroscopy that could not be suctioned and required flushing with water. The volume of flush, the site at which it was used and the total procedure times were recorded.

RESULTS

All three groups showed no statistical difference for age, sex ratio, procedure priority or indication. The mean volume of flush required to obtain clear mucosa was significantly less in the solution group compared with the other groups. The mean overall procedure time was also less in the solution group compared with the other groups.

DISCUSSION

Premedication with N-acetylcysteine and simethicone markedly improves mucosal visibility during gastroscopy. It also reduces the time taken for the procedure. This low-cost and well-tolerated intervention may improve detection of early neoplasia.

Gastric examination with a magnetically guided capsule endoscope: An analysis of 55 volunteers

AIM: To investigate the feasibility of conducting gastric examination with a magnetically guided capsule endoscope.

METHODS: Fifty-five volunteers who underwent gastric examination with a magnetically guided capsule endoscope were included in this study. All participants swallowed the capsule endoscope, which was controlled by an external magnetic field control device to reach various sites of the esophagus and stomach.

RESULTS: Fifty-four volunteers completed the endoscopic procedure, and the mean operating time was 24.5 ± 5.5 min. One volunteer prematurely ended the examination because his gastric emptying was too fast and the capsule endoscope entered into the duodenum in five minutes. Of all the 55 volunteers, 45 were diagnosed with superficial gastritis, 3 with superficial gastritis with bile reflux, 1 with gastric antral tumor, and 4 showed no abnormality. All volunteers had no discomfort in the examination process.

CONCLUSION: Magnetically guided capsule endoscopy is effective and safe in conducting gastric examination.

Prospective controlled study on the effects of polyethylene glycol in capsule endoscopy

AIM: To prospectively confirm whether a small amount of polyethylene glycol (PEG) ingested after swallowing endoscopy capsule improves image quality and completion rate.

METHODS: Forty-four consecutive patients referred to us for capsule endoscopy (CE) were randomized to two groups. All patients were restricted to clear fluids for 12 h before the examination. Patients in group A (22 cases) received no additional preparation, while those in group B (20 cases) ingested 500 mL of PEG within a 2 h period starting 30 min after swallowing the capsule. Clear fluids and meals were allowed 2 h and 4 h after capsule ingestion, respectively. Image quality was assessed as the percentage of visualized bowel surface area as follows: 1: < 25%; 2: 25%-49%; 3: 50%-74%; 4: 75%-89%; 5: > 90%. The small bowel record was divided into five segments by time, and the score for each segment was evaluated. All CE examinations were performed with the Pillcam SB capsule endoscopy system (Given Imaging Co. Ltd., Yoqnem).

RESULTS: This study ended in December 2009, because sample size was considered large enough. A total of 44 patients were enrolled. Two patients in group B were excluded from the analysis because small bowel images could not be obtained from these patients; one had a full stomach, while the other presented with a massive gastric bleed. Thus, 22 patients from group A and 20 patients from group B completed the study. There was no significant difference in age (P = 0.22), sex (P = 0.31), and indication for CE. No significant adverse events occurred in any of the study patients. In group A, image quality deteriorated as the capsule progressed distally. However, in group B, image quality was maintained to the distal small bowel. In each of the five segments, the visibility score was significantly higher in group B than in group A (segment 1: 4.3 ± 0.7 vs 4.7 ± 0.5, P = 0.03; segment 2: 4.2 ± 0.9 vs 4.8 ± 0.4, P = 0.01; segment 3: 4.0 ± 1.0 vs 4.6 ± 0.7, P = 0.04; segment 4: 3.6 ± 1.1 vs 4.5 ± 0.6, P = 0.003; segment 5: 2.7 ± 1.0 vs 4.4 ± 0.8, P = 0.00004). Thus, the use of PEG during CE examination significantly improved image quality in all time segments, and this effect was more pronounced in the distal ileum. The completion rate to the cecum was not significantly different between groups A and B (81.8% vs 85.0%, P = 0.89). There was no difference in the gastric transit time between groups (36.2 ± 35.0 min vs 54.0 ± 56.6 min, P = 0.23), but the small bowel transit time was significantly longer in group A than in group B (246.0 ± 107.0 min vs 171.0 ± 104.0 min, P = 0.04).

CONCLUSION: The ingestion of a small amount of PEG after the swallowing of an endoscopy capsule significantly improved CE image quality, but did not enhance the completion rate to the cecum.

Double-contrast barium enteroclysis as a patency tool for nonsteroidal anti-inflammatory drug-induced enteropathy

BACKGROUND

Evaluating small bowel patency is recommended for capsule endoscopy in patients suspected of nonsteroidal anti-inflammatory drug-induced (NSAID) enteropathy.

AIMS

The aim of this investigation was to examine whether radiography is a candidate of patency tool in NSAID enteropathy.

METHODS

We reviewed double-contrast barium enteroclysis in 21 patients with NSAID enteropathy diagnosed either by capsule endoscopy or balloon-assisted endoscopy. The endoscopic findings were classified into circular ulcers, linear ulcers and small mucosal defects. The radiographic signs of the corresponding endoscopic findings were retrieved and the depiction rate was calculated.

RESULTS

Of the 21 patients, endoscopy detected circular ulcers, linear ulcers, and small ulcers in 12, 3 and 12 patients, respectively. Small bowel radiography depicted circular narrowing as pseudo-folds in 10 patients (83%) and linear ulcers as eccentric rigidity in 2 patients (67%). However, radiography was able to depict small mucosal defects in only 3 patients (17%). Two of 5 patients with pseudo-folds experienced retention of the capsule.

CONCLUSION

"Pseudo-folds" is a sign corresponding to circular ulcer in NSAID enteropathy, which may be predictive of capsule retention.

Image-enhanced capsule endoscopy based on the diagnosis of vascularity when using a new type of capsule

BACKGROUND

Small-bowel lesions responsible for obscure GI bleeding are often accompanied by vascular abnormalities. Image-enhanced capsule endoscopy could be advantageous in detecting these abnormalities.

OBJECTIVE

To evaluate the image representation performance of the contrast capsule.

DESIGN

Feasibility study.

SETTING

University hospital.

PATIENTS AND INTERVENTIONS

Consecutive patients with obscure GI bleeding swallowed the contrast capsule.

MAIN OUTCOME MEASUREMENTS

Image representation performance of the contrast capsule and the appearance of small-bowel lesions in image-enhanced capsule endoscopy.

RESULTS

Twenty patients (16 males and 4 females) underwent capsule endoscopy during the study period. Small-bowel abnormality was detected, including 5 cases of multiple erosions or ulcers, 1 case of Peutz-Jeghers syndrome, and 1 case of angiectasia. The contrast capsule visualized the lesions with high vascularity in a dark green color with a strong color contrast compared with the surrounding normal mucosa, which appeared as a brownish color.

LIMITATIONS

Small, single-center, nonrandomized study.

CONCLUSION

This feasibility study demonstrated the image representation characteristics of the contrast capsule. The diagnostic yield of this technology should be investigated in a future randomized trial.

Advances in complete small-bowel examination by capsule endoscopy

Capsule endoscopy (CE) has a battery life of 8 h, during which time complete small-bowel examination can be achieved in most cases. However, in 10-30% of cases, the capsule cannot reach the ileocecal valve before the end of the life of the capsule's battery due to factors other than mechanical bowel obstruction. Incomplete examination of the entire small bowel leaves room for missing lesions. Some studies have shown that diabetes mellitus can lead to gastroparesis and increase gastric transit time (GTT), while history of abdominal surgery can increase small bowel transit time (SBTT). Therefore, these two factors can decrease the rate of complete small-bowel examination by CE. Purgative bowel cleansing can improve the detectability and image quality of CE, but has no significant impact on GTT, SBTT and CR. Prokinetic drugs, real-time CE, right lateral position, and chewing-gum are all under research for increasing CR. In future studies, emphasis should be placed in improving the diagnostic ability of CR and ensuring optimal intervention for patients with high risk factors for incomplete small-bowel examination.

Factors associated with the clinical impact of capsule endoscopy in patients with overt obscure gastrointestinal bleeding

BACKGROUND AND STUDY AIMS

Capsule endoscopy (CE) does not necessarily identify positive findings in patients with overt obscure gastrointestinal bleeding (OGIB). We aimed to identify factors predictive of positive CE findings and those of re-bleeding after negative CE in overt OGIB.

PATIENTS AND METHODS

We retrospectively analyzed 68 patients who underwent CE for overt OGIB. CE findings, therapeutic interventions, and clinical course after CE were reviewed. Clinical variables associated with positive CE findings and those associated with re-bleeding after negative CE findings were investigated.

RESULTS

Positive CE finding was found in 36 (53%) patients. Marked decrease in hemoglobin value [OR; 18.8, 95% CI; 3.4-152.0] and earlier CE examination within a week after the last episode of bleeding [OR; 8.0, 95% CI; 2.2-35.9] were factors associated with positive CE findings. Nine (28%) of 32 patients with negative CE findings re-bled. Marked decrease in hemoglobin value was more frequent in patients with re-bleeding than those without (P = 0.07).

CONCLUSION

Patients with massive and overt OGIB are the best candidates for CE. Earlier CE, virtually within a week, contributes to the better diagnostic yield of the procedure. Careful follow-up seems necessary for patients with massive bleeding even in cases of negative CE findings.

Can we improve the diagnostic yield of small bowel video-capsule endoscopy?

Video-capsule endoscopy has revolutionized the examination of small bowel mucosa. However, this modality is relatively young and its diagnostic yield is low. Herein, we discuss different approaches to improve examination’s diagnostic yield. There are strong data supporting some of them while there is speculation about the rest. As capsule endoscopy continues to evolve there is also a strong belief that technology will overcome at least some of the obstacles that hamper capsule endoscopy’s diagnostic yield sometime in the near future.