Anastasios Koulaouzidis

Small-bowel capsule endoscopy: a ten-point contemporary review.

The introduction of capsule endoscopy (CE) in clinical practice increased the interest for the study of the small-bowel. Consequently, in about 10 years, an impressive quantity of literature on indications, diagnostic yield (DY), safety profile and technical evolution of CE has been published as well as several reviews. At present time, there are 5 small-bowel capsule enteroscopy (SBCE) models in the worldwide market. Head-to-head trials have showed in the great majority of studies comparable results in terms of DY, image quality and completion rate. CE meta-analyses formed the basis of national/international guidelines; these guidelines place CE in a prime position for the diagnostic work-up of patients with obscure gastrointestinal bleeding, known and/or suspected Crohns disease and possible small-bowel neoplasia. A 2-L polyethylene glycol-based purge, administered the day before the procedure, is the most widely practiced preparation regimen. Whether this regimen can be further improved (i.e., by further decreasing its volume, changing the timing of administration, coupling it with prokinetics and/or other factors) or if it can really affect the DY, is still under discussion. Faecal calprotectin has been used in SBCE studies in two settings: in patients taking non-steroidal anti-inflammatory drugs, to evaluate the type and extent of mucosal damage and, more importantly from a clinical point of view, in patients with known or suspected Crohns disease for assessment of inflammation activity. Although there is still a lot of debate around the exact reasons of SBCE poor performance in various small-bowel segments, it is worth to remember that the capsule progress is non-steerable, hence more rapid in the proximal than in lower segments of the small-bowel. Capsule aspiration, a relatively unexpected complication, has been reported with increasing frequency. This is probably related with the increase in the mean age of patients undergoing CE. CE video review is a time-consuming procedure. Therefore, several attempts have been made to develop technical software features, in order to make CE video analysis easier and shorter (without jeopardizing its accuracy). Suspected Blood Indicator, QuickView and Fujinon Intelligent Chromo Endoscopy are some of the software tools that have been checked in various clinical studies to date.

Software for enhanced video capsule endoscopy: challenges for essential progress

Video capsule endoscopy (VCE) has revolutionized the diagnostic work-up in the field of small bowel diseases. Furthermore, VCE has the potential to become the leading screening technique for the entire gastrointestinal tract. Computational methods that can be implemented in software can enhance the diagnostic yield of VCE both in terms of efficiency and diagnostic accuracy. Since the appearance of the first capsule endoscope in clinical practice in 2001, information technology (IT) research groups have proposed a variety of such methods, including algorithms for detecting haemorrhage and lesions, reducing the reviewing time, localizing the capsule or lesion, assessing intestinal motility, enhancing the video quality and managing the data. Even though research is prolific (as measured by publication activity), the progress made during the past 5 years can only be considered as marginal with respect to clinically significant outcomes. One thing is clear—parallel pathways of medical and IT scientists exist, each publishing in their own area, but where do these research pathways meet? Could the proposed IT plans have any clinical effect and do clinicians really understand the limitations of VCE software? In this Review, we present an in-depth critical analysis that aims to inspire and align the agendas of the two scientific groups.

Fecal calprotectin: A selection tool for small bowel capsule endoscopy in suspected IBD with prior negative bi-directional endoscopy

Abstract Background and aim. Fecal calprotectin (FC) is a non-invasive marker of gastrointestinal inflammation with advocated diagnostic precision in distinguishing inflammatory bowel disease (IBD) from non-IBD diagnoses. FC correlates with abnormalities seen on small bowel barium radiology, but little data exist in relation with small bowel capsule endoscopy (SBCE). To investigate the value of FC as a selection tool for further investigation of the small bowel with SBCE, in a cohort of patients who had negative bi-directional endoscopies, but with continuing clinical suspicion of Crohns disease (CD). Methods. We retrospectively correlated the findings of SBCE with FC levels in patients referred with clinical suspicion of CD and negative bi-directional endoscopies. Only patients with FC results prior to the SBCE test were included; in cases of multiple FC determinations, the value closest to the SBCE date was selected. Medications history including usage of aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) was made available for all patients. SBCE findings were analyzed against final diagnosis and FC values. Results. Seventy adult patients were studied (53 females, 17 males). Three cases were excluded, due to capsule retention in the stomach. Median time from FC measurement to SBCE was 62 days. Twenty-three patients had normal FC (≤50 μg/g) and in all those the SBCE was normal. Forty-four patients had FC >50 μg/g; in this group, nine patients had FC between 51 and 100 μg/g and all had a normal SBCE. Thirty-five patients had FC levels >100 μg/g; of those, 15 (42.85%) had SBCE findings compatible with CD and mean FC levels 326 μg/g (range 116–1430 μg/g). A definitive clinical diagnosis of CD, based on subsequent follow-up, was made in 10/35 (28.5%) of patients. These 10 patients were within the subgroup of 15 patients with positive SBCE findings and had median FC levels 368 μg/g (range 235–1430 μg/g). Conclusions. Measurement of FC levels prior to referral for SBCE is a useful tool to select patients with possible small bowel CD. A FC >100 μg/g is good predictor of positive SBCE findings, while FC >200 μg/g was associated with higher SBCE yield (65%) and confirmed CD in 50% of cases. Patients with FC between 50 and 100 μg/g had normal SBCE, despite symptoms suggestive of IBD. In all patients with clinical suspicion of CD and negative bi-directional endoscopies, FC assessment should be carried out prior to their referral for SBCE. Where FC is <100 μg/g (NPV 1.0), SBCE is not indicated.

Diagnostic yield of small-bowel capsule endoscopy in patients with iron-deficiency anemia: a systematic review

BACKGROUND Iron-deficiency anemia (IDA) is the most common cause of anemia worldwide. Current guidelines recommend the use of small-bowel capsule endoscopy (SBCE) in IDA. Evidence of the validity of SBCE in patients with IDA alone is still limited. OBJECTIVE To assess the diagnostic yield (DY) of SBCE in IDA by pooling data from relevant studies. DESIGN Systematic review and meta-analysis. Fixed-effects or random-effects models were used as appropriate. SETTING Studies that estimated the DY of SCBE in IDA were identified. Two investigators independently conducted the search and data extraction. PATIENTS A total of 24 studies enrolling 1960 patients with IDA who underwent SBCE were included. MAIN OUTCOME MEASUREMENTS Per-patient DY, with 95% confidence intervals. Subgroup analysis was also performed. RESULTS The pooled DY of SBCE in IDA, evaluated by a random-effects model, was 47% (95% CI, 42%-52%), but there was statistically significant heterogeneity among the included studies (inconsistency index [I(2)] = 78.8%, P < .0001). The pooled DY of SBCE in studies focused solely on patients with IDA (subset 1, 4 studies) was 66.6% (95% CI, 61.0%-72.3%; I(2) = 44.3%); conversely, that of studies not focusing only on IDA patients (subset 2, 20 studies) was 44% (95% CI, 39%-48%; I(2) = 64.9%). In particular, more vascular (31% vs 22.6%, P = .007), inflammatory (17.8% vs 11.3%, P = .009), and mass/tumor (7.95% vs 2.25%, P < .0001) lesions were detected with SBCE in patients participating in the studies in subset 1. LIMITATIONS Heterogeneity of studies, retrospective design, and selection bias. CONCLUSIONS This analysis demonstrates the validity of SBCE in the investigation of patients with IDA and negative findings on a previous diagnostic workup, although certain factors such as heterogeneity and quality of the included studies should be taken into account.

Small bowel capsule endoscopy in the management of established Crohn's disease: clinical impact, safety, and correlation with inflammatory biomarkers.

Background:Multiple studies have established the superior diagnostic accuracy of video capsule endoscopy (VCE) for the diagnosis of small bowel (SB) Crohns disease (CD). However, data on the clinical impact of VCE in patients with established CD are scarce. The aim of this study was to examine the impact and safety of VCE on the clinical management of patients with established CD. Methods:A retrospective, multicenter, cross-sectional study. The study cohort included consecutive patients with established SB CD who underwent VCE in 4 tertiary referral centers (1 Canada, 1 Sweden, and 2 United Kingdom) from January 2008 to October 2013. Patients were excluded if VCE was performed as a part of the initial diagnostic workup. The presence of SB mucosal inflammation was quantified using the Lewis score. Inflammatory biomarkers (C-reactive protein and fecal calprotectin) were measured and correlated with the Lewis score. Results:The study included 187 patients. No SB inflammation was observed in 28.4%, mild-to-moderate inflammation in 26.6%, and moderate-to-severe inflammation in 45% of the patients (median Lewis score, 662; range, 0–6400). A change in management was recommended in 52.3% of the patients based on VCE findings. Elevated C-reactive protein, fecal calprotectin, or the combination of both were poorly correlated with significant SB inflammation. SB capsule retention occurred in 4 patients (2.1%). Conclusions:VCE in patients with established CD is safe, and the results often have a significant clinical impact. VCE should not be limited to CD patients with positive inflammatory markers because their predictive value for significant SB inflammation is poor.

Do prokinetics influence the completion rate in small-bowel capsule endoscopy? A systematic review and meta-analysis

Abstract Background: The use of purging for bowel cleansing prior to small-bowel capsule endoscopy (SBCE) has now been established in clinical practice. Despite that, the number of incomplete SBCEs is still around 15–20%. To date, the use of prokinetics in SBCE – aiming to improve completion rate (CR) – remains a contentious issue resulting in lack of consensus among capsule experts. Methods: Extensive medical literature searches were conducted (to November 2012), using suitable MeSH terms and keywords, in search of studies that compared capsule ingestion with prokinetic agents vs. controls or placebo. We examined the effects of prokinetic administration on SBCE CR (primary end point), as well as on the following secondary end points: diagnostic yield (DY), gastric transit time (GTT) and small-bowel transit time (SBTT) by meta-analysis of all relevant studies. Results: A total of 17 eligible studies (14 prospective, 3 retrospective) were identified, including 1028 individuals who ingested the capsule with no prokinetic vs. 876 who received a prokinetic. Overall, there was a higher CR in patients who ingested the capsule with prokinetics vs. controls (OR [95% CI]: 1.96 [1.38–2.78]). Of the two most readily available prokinetics, metoclopramide was associated with superior SBCE CR vs. control (OR [95% CI]: 2.8 [1.35–3.21]), while erythromycin showed no benefit (OR [95% CI]: 1.36 [0.61–3.03]). Where prokinetics were used alone, neither metoclopramide nor erythromycin showed any benefit on CR. There was no benefit of prokinetics (over controls) on DY. However, metoclopramide had a significant effect on GTT and SBTT. Limitations: The majority of the included studies were heterogeneous, and the effect of prokinetics on image quality and mucosal visualization was not examined. Conclusion: Our pooled data shows that the use of prokinetics for capsule ingestion improves CR in SBCE. This effect appears to be particularly evident with metoclopramide, when used concurrently with purging and/or use of real-time monitoring. In a small number of studies, erythromycin showed – through its gastrokinetic effect – marginal benefit. No prokinetic has a beneficial effect on SBCE DY.

Wireless endoscopy in 2020: Will it still be a capsule?

Currently, the major problem of all existing commercial capsule devices is the lack of control of movement. In the future, with an interface application, the clinician will be able to stop and direct the device into points of interest for detailed inspection/diagnosis, and therapy delivery. This editorial presents current commercially-available new designs, European projects and delivery capsule and gives an overview of the progress required and progress that will be achieved -according to the opinion of the authors- in the next 5 year leading to 2020.

Automatic lesion detection in capsule endoscopy based on color saliency: closer to an essential adjunct for reviewing software

BACKGROUND The advent of wireless capsule endoscopy (WCE) has revolutionized the diagnostic approach to small-bowel disease. However, the task of reviewing WCE video sequences is laborious and time-consuming; software tools offering automated video analysis would enable a timelier and potentially a more accurate diagnosis. OBJECTIVE To assess the validity of innovative, automatic lesion-detection software in WCE. DESIGN/INTERVENTION A color feature-based pattern recognition methodology was devised and applied to the aforementioned image group. SETTING This study was performed at the Royal Infirmary of Edinburgh, United Kingdom, and the Technological Educational Institute of Central Greece, Lamia, Greece. MATERIALS A total of 137 deidentified WCE single images, 77 showing pathology and 60 normal images. RESULTS The proposed methodology, unlike state-of-the-art approaches, is capable of detecting several different types of lesions. The average performance, in terms of the area under the receiver-operating characteristic curve, reached 89.2 ± 0.9%. The best average performance was obtained for angiectasias (97.5 ± 2.4%) and nodular lymphangiectasias (96.3 ± 3.6%). LIMITATIONS Single expert for annotation of pathologies, single type of WCE model, use of single images instead of entire WCE videos. CONCLUSION A simple, yet effective, approach allowing automatic detection of all types of abnormalities in capsule endoscopy is presented. Based on color pattern recognition, it outperforms previous state-of-the-art approaches. Moreover, it is robust in the presence of luminal contents and is capable of detecting even very small lesions.

The use of small-bowel capsule endoscopy in iron-deficiency anemia alone; be aware of the young anemic patient.

Abstract Background & aim. The role of Small-Bowel Capsule Endoscopy (SBCE) in Iron Deficiency Anemia (IDA) alone is still under validation. We aim to assess the usefulness of SBCE in patients with IDA alone; Methods. Retrospective study; patients with IDA (no GI symptoms or known previous diagnosis), who underwent SBCE were included. SBCE findings were classified as clinically significant/sinister (small-bowel malignancy, significant/sinister inflammation and/or strictures and coeliac disease) or vascular, i.e., signifcant/angioectasias (P1/P2 lesions); Results. A total of 221 (151F/70M) patients had SBCE for IDA as the sole indication. The diagnostic yield (DY) was 30.7% (68/221). The DY for significant/sinister pathology and significant/angioectasias was 9% and 21.7%, respectively. In those ≤40 years (20; 13F/7M), significant pathology was found in 25% (5/20); in the >40-year group (201; 138F/63M), significant/sinister pathology was found in 7.5% (15/201), p = 0.0231. None of the patients ≤40 years had angioectasias, such lesions were found in 48/201 (21.7%) of those >40 years, p = 0.009. Fifty percent of those >80 years (16; 12F/4M) had angioectasias, but none had significant/sinister pathology (p = 0.0126). On multiple regression analysis, only prior blood transfusion was predictive of higher DY in SBCE; Conclusions. IDA alone is one of the main indications (27%) for referral to SBCE; the majority of patients are >40 years. In our cohort, the DY of SBCE for IDA was 30.7% and the commonest finding was angioectasias. The detection rate of sinister small-bowel pathology for those >40 years is low decreasing to zero in the >80 age group. In contrast, 25% of those ≤40 years had a sinister diagnosis.

Chromoendoscopy in small bowel capsule endoscopy: Blue mode or Fuji Intelligent Colour Enhancement?

INTRODUCTION Virtual chromoendoscopy is used to enhance surface patterns and colour differences. One type of virtual chromoendoscopy is the Fuji Intelligent Colour Enhancement (FICE). Although widely applied in conventional endoscopy, data on FICE application in capsule endoscopy are limited. Furthermore, the validity of Blue filter (feature of RAPID(®) software) has not been examined. AIM/S: We aimed to qualitatively evaluate the use of FICE and Blue filter enhancement, in images of lesions obtained during small bowel capsule endoscopy, comparing them with similar, conventional (white light) images. METHODS A total of 167 images (6 different lesion categories) obtained from 200 capsule endoscopy examinations. Two gastroenterologists examined the images with white light, FICE and Blue filter in regards to the visibility of blood vessels, the contrast of the mucosal surface, and the demarcation of lesion borders. The agreed scores were: improved, similar, worse. Inter-observer agreement was calculated. RESULTS For all lesion categories, Blue filter provided image improvement (compared to white light) in 83%, (inter-observer agreement: 0.786). With FICE 1, improvement was observed in 34%, worse image in 55.9%, (inter-observer agreement: 0.646). With FICE 2, improvement was observed in 8.6%, worse in 77.5%, (inter-observer agreement: 0.617). With FICE 3, improvement was seen in 7.7%, worse in 79.9% (inter-observer agreement: 0.669). CONCLUSION Comparing with FICE, Blue filter offers better image enhancement in capsule endoscopy.