Wireless capsule endoscopy

Small bowel transit time of capsule endoscopy as a factor for the detection of lesions in potential small bowel bleeding

BACKGROUND

the relationship between small bowel transit time (SBTT) of the capsule endoscopy (CE) and the diagnosis of small bowel bleeding (SBB) is controversial.

OBJECTIVE

to evaluate the relationship between SBTT and CE and the identification of SBB.

MATERIAL AND METHODS

CE was divided according to SBTT into < 4 hours and ≥ 4 hours.

RESULTS

CE with SBTT ≥ 4 hours identified more angioectasias (p = 0.023), single lesions (p = 0.029) and jejunal lesions (p = 0.001) with an OR of 3.13 (95% CI, 1.61-6.10, p = 0.001) to identify the cause of SBB.

CONCLUSIONS

CE SBTT of ≥ 4 hours increases the diagnosis of SBB.

The Clinician's Guide to Suspected Small Bowel Bleeding

Small bowel bleeding accounts for 5-10% of gastrointestinal bleeding. With the advent of capsule endoscopy, device-assisted enteroscopy, and multiphase CT scanning, a small bowel source can now be found in many instances of what has previously been described as obscure gastrointestinal bleeding. We present a practical review on the evaluation and management of small bowel bleeding for the practicing clinician.

Massive Gastrointestinal Bleeding Secondary to Ileal Invasion by Ventral Hernioplasty Mesh

Surgical mesh migration is a very rare cause of gastrointestinal (GI) bleeding. We report a 56-year-old woman who presented with massive GI bleeding 10 years after ventral hernioplasty with mesh. Esophagoduodenoscopy and colonoscopy were normal. Computed tomographic angiography of the abdomen showed no active GI bleeding or bowel perforation. Tagged red blood cell scan suggested active bleeding in the proximal ileum. Exploratory laparotomy showed the ventral hernia mesh eroding into the ileum. This case emphasizes the limitations of radiologic imaging in evaluating GI bleeding and the recognition of ventral mesh migration and invasion as a potential etiology of small-bowel bleeding.

No significant difference in clinically relevant findings between Pillcam® SB3 and Pillcam® SB2 capsules in a United States veteran population

BACKGROUND

Capsule endoscopy (CE) allows for a non-invasive small bowel evaluation for a wide range of gastrointestinal (GI) symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam^® SB3 (SB3) capsule is one such technology that offers an adaptive frame rate advantage over the previous versions of the capsule the Pillcam^® SB2 (SB2). Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking.

AIM

To evaluate the clinically relevant findings of SB3 and SB2 capsules in a population of United States veterans.

METHODS

A retrospective analysis of 260 consecutive CE studies was performed including 130 SB3 and 130 SB2 capsule studies. Recorded variables included: age, gender, type of capsule, body mass index, exam completion, inpatient status, opioid use, diabetes, quality of preparation, gastric transit time, small bowel transit time, indication, finding, and if the exam resulted in a change in clinical management. The primary outcome measured was the detection of clinically relevant findings between SB3 and SB2 capsules.

RESULTS

Mean age of the study population was 67.1 ± 10.4 years and 94.2% of patients were male. Of these 28.1% were on opioid users. The most common indications for capsule procedure were occult GI bleeding (74.6%) and overt GI bleeding (14.6%). Rates of incomplete exam were similar between SB3 and SB2 groups (16.9% vs 9.2%, P = 0.066). The overall rate of clinically relevant finding was 48.9% in our study. No significant difference was observed in SB3 vs SB2 capsules for clinically relevant findings (46.2% vs 51.5%, P = 0.385) or change in clinical management (40.8% vs 50.0%, P = 0.135).

CONCLUSION

Our study found no significant difference in clinically relevant findings between SB3 and SB2 capsules.

Automatic detection of erosions and ulcerations in wireless capsule endoscopy images based on a deep convolutional neural network

BACKGROUND AND AIMS

Although erosions and ulcerations are the most common small-bowel abnormalities found on wireless capsule endoscopy (WCE), a computer-aided detection method has not been established. We aimed to develop an artificial intelligence system with deep learning to automatically detect erosions and ulcerations in WCE images.

METHODS

We trained a deep convolutional neural network (CNN) system based on a Single Shot Multibox Detector, using 5360 WCE images of erosions and ulcerations. We assessed its performance by calculating the area under the receiver operating characteristic curve and its sensitivity, specificity, and accuracy using an independent test set of 10,440 small-bowel images including 440 images of erosions and ulcerations.

RESULTS

The trained CNN required 233 seconds to evaluate 10,440 test images. The area under the curve for the detection of erosions and ulcerations was 0.958 (95% confidence interval [CI], 0.947-0.968). The sensitivity, specificity, and accuracy of the CNN were 88.2% (95% CI, 84.8%-91.0%), 90.9% (95% CI, 90.3%-91.4%), and 90.8% (95% CI, 90.2%-91.3%), respectively, at a cut-off value of 0.481 for the probability score.

CONCLUSIONS

We developed and validated a new system based on CNN to automatically detect erosions and ulcerations in WCE images. This may be a crucial step in the development of daily-use diagnostic software for WCE images to help reduce oversights and the burden on physicians.

Applications of wireless capsule endoscopy in pediatric age: an update

The small bowel has often been considered the mysterious "black hole" of the gastrointestinal tract. With regards to this, the development of the wireless capsule endoscopy (WCE) has represented a turning point. It is a non-invasive technique, enabling an excellent visualization of the small bowel (SB) mucosa without the use of radiation. The WCE was approved by the Food and Drug Administration (FDA) in 2001 for adults and in 2004 for children. The aim of the present review is to provide an update on indications, diagnostic yield, safety and limitations of WCE in children. Even though literature regarding the use of WCE in pediatric age is more limited than in adults, WCE is a useful and safe diagnostic tool for the exploration of the small bowel also in children. The indications for WCE are similar at any age, however the main indication in children is Crohn's disease (CD), while in the adults is the research of SB bleeding. The main limitation in pediatric age is the possibility for younger children to swallow the capsule. WCE in pediatric is a rapidly advancing technology and has the potential to further transform the evaluation and management of SB disease.

Video capsule endoscopy vs double-balloon enteroscopy in the diagnosis of small bowel bleeding: A systematic review and meta-analysis

AIM

To compare the diagnostic accuracy of video capsule endoscopy (VCE) and double-balloon enteroscopy (DBE) in cases of obscure gastrointestinal bleeding (OGIB) of vascular origin.

METHODS

MEDLINE (via PubMed), LILACS (via BVS) and Cochrane/CENTRAL virtual databases were searched for studies dated before 2017. We identified prospective and retrospective studies, including observational, cohort, single-blinded and multicenter studies, comparing VCE and DBE for the diagnosis of OGIB, and data of all the vascular sources of bleeding were collected. All patients were subjected to the same gold standard method. Relevant data were then extracted from each included study using a standardized extraction form. We calculated study variables (sensitivity, specificity, prevalence, positive and negative predictive values and accuracy) and performed a meta-analysis using Meta-Disc software.

RESULTS

In the per-patient analysis, 17 studies (1477 lesions) were included. We identified 3150 exams (1722 VCE and 1428 DBE) in 2043 patients and identified 2248 sources of bleeding, 1467 of which were from vascular lesions. Of these lesions, 864 (58.5%) were diagnosed by VCE, and 613 (41.5%) were diagnosed by DBE. The pretest probability for bleeding of vascular origin was 54.34%. The sensitivity of DBE was 84% (95%CI: 0.82-0.86; heterogeneity: 78.00%), and the specificity was 92% (95%CI: 0.89-0.94; heterogeneity: 92.0%). For DBE, the positive likelihood ratio was 11.29 (95%CI: 4.83-26.40; heterogeneity: 91.6%), and the negative likelihood ratio was 0.20 (95%CI: 0.15-0.27; heterogeneity: 67.3%). Performing DBE after CE increased the diagnostic yield of vascular lesion by 7%, from 83% to 90%.

CONCLUSION

The diagnostic accuracy of detecting small bowel bleeding from a vascular source is increased with the use of an isolated video capsule endoscope compared with isolated DBE. However, concomitant use increases the detection rate of the bleeding source.

The diagnostic ability of SPECT/CT fusion imaging for gastrointestinal bleeding: a retrospective study

Background

Blood loss from the gastrointestinal tract can be an acute and life-threatening event. For the treatment of gastrointestinal bleeding, it is important to accurately detect gastrointestinal bleeding and to localize the sites of bleeding. The purpose of this study was to retrospectively assess the capabilities of SPECT/CT in the diagnosis of gastrointestinal bleeding by a comparison with planar imaging alone as well as planar and SPECT.

Methods

We conducted a retrospective analysis of 20 patients (21 examinations) who underwent gastrointestinal bleeding scintigraphy in the past 7 years and in whom the bleeding site was identified by endoscopy or capsule endoscopy, or in whom no evidence of gastrointestinal bleeding was identified during the clinical course. Five patients (5 examinations) were diagnosed by planar imaging (planar group). Eight patients (9 examinations) were diagnosed by planar imaging and SPECT (planar + SPECT group). Seven patients (7 examinations) were diagnosed by planar imaging and SPECT/CT (planar + SPECT/CT group). We calculated the diagnostic ability of each method in detecting the presence of bleeding, as well as the ability of each method to identify the sites of bleeding. The sensitivity, specificity, and accuracy of the methods were compared.

Results

The diagnostic ability of the three imaging methods in detecting the presence of gastrointestinal bleeding was as follows. Planar imaging showed 100% sensitivity (3/3), 100% specificity (2/2), and 100% accuracy (5/5). Planar + SPECT imaging showed 85.7% sensitivity (6/7), 100% specificity (2/2), and 88.9% accuracy (8/9). Planar + SPECT/CT imaging showed 100% sensitivity (6/6), 100% specificity (1/1), and 100% accuracy (7/7). The diagnostic ability of the three modalities in detecting the site of bleeding was as follows: planar, 33.3% (1/3); planar + SPECT, 71.4% (5/7); and planar + SPECT/CT, 100% (6/6).

Conclusions

All 3 imaging methods showed good accuracy in detecting the presence of gastrointestinal bleeding. The addition of SPECT or SPECT/CT made the anatomical position of the uptake clear and contributed to the localization of the site of gastrointestinal bleeding. Planar + SPECT/CT imaging therefore showed the highest diagnostic ability for detecting the site of gastrointestinal bleeding.

A Deeper Look at the Small Bowel: Training Pathways in Video Capsule Endoscopy and Device-Assisted Enteroscopy

BACKGROUND

Although there are guidelines for video capsule endoscopy (VCE) and device-assisted enteroscopy (DAE), little is known about fellowship training in these technologies.

AIMS

The aims were to better characterize current small bowel endoscopy training in 3-year GI fellowship programs and 4th-year advanced endoscopy programs in the U.S.

METHODS

We developed an online multiple-choice survey to assess current GI fellowship program training in small bowel endoscopy. The survey was distributed via email to GI fellowship program directors in the U.S.

RESULTS

Of the 168 program directors contacted, 59 responded (response rate = 35.1%). There was no statistically significant difference in the availability of VCE or DAE between respondents and non-respondents. VCE training was universally available in 3-year training programs, with 84.8% (50/59) requiring it for fellows. The majority of 3-year GI fellows graduated with independence in VCE: 83.1% (49/59) of programs reported "most" or "all" graduates were able to read independently. DAE techniques were available in 86.4% of training programs (51/59). Training in DAE was more limited and shared between 3-year and 4th-year programs: 12.1% (7/58) of 3-year programs required training in DAE and 22.9% (8/35) of 4th-year programs required training in DAE .

CONCLUSIONS

Training in VCE is widely available in U.S. GI fellowship programs, although programs have different ways of incorporating this training into the curriculum and of measuring competency. While DAE technology was available in the majority of programs, training was less frequently available, and training is shared between 3-year fellowship programs and 4th-year advanced endoscopy programs .

Computer-aided detection of small intestinal ulcer and erosion in wireless capsule endoscopy images

A novel computer-aided detection method based on deep learning framework was proposed to detect small intestinal ulcer and erosion in wireless capsule endoscopy (WCE) images. To the best of our knowledge, this is the first time that deep learning framework has been exploited on automated ulcer and erosion detection in WCE images. Compared with the traditional detection method, deep learning framework can produce image features directly from the data and increase recognition accuracy as well as efficiency, especially for big data. The developed method included image cropping and image compression. The AlexNet convolutional neural network was trained to the database with tens of thousands of WCE images to differentiate lesion and normal tissue. The results of ulcer and erosion detection reached a high accuracy of 95.16% and 95.34%, sensitivity of 96.80% and 93.67%, and specificity of 94.79% and 95.98%, correspondingly. The area under the receiver operating characteristic curve was over 0.98 in both of the networks. The promising results indicate that the proposed method has the potential to work in tandem with doctors to efficiently detect intestinal ulcer and erosion.

Video capsule endoscopy is safe and effective in suspected small bowel bleeding among left ventricular assist device recipients

Introduction:

Suspected small bowel bleeding is frequently encountered in left ventricular assist device recipients and the identification of the culprit lesion may be challenging. Data regarding the safety and yield of small bowel capsule in the investigation of suspected small bowel bleeding are limited. We aimed to evaluate the safety and efficacy of small bowel video capsule endoscopy for the investigation of suspected small bowel bleeding among left ventricular assist device recipients.

Methods:

Patients with left ventricular assist device who underwent video capsule endoscopy for the investigation of suspected small bowel bleeding were identified. Suspected small bowel bleeding was defined as the presence of overt bleeding at least 30 days following left ventricular assist device implantation with no identifiable cause in upper and lower endoscopy.

Results:

A total of 10 patients with left ventricular assist device associated suspected small bowel bleeding performed 12 small bowel capsule endoscopies between January 2008 and December 2015 at our tertiary medical care facility. There were no cases of capsule retention or any other serious adverse events during the exams. A significant finding was identified in 8 out of 10 patients, including 3 cases of small bowel angioectasia, 2 cases of small bowel ulcers, 1 case of cecal polyp, and 2 cases of active bleeding with no apparent bleeding source. Small bowel enteroscopy identified and treated bleeding angioectasia in the latter two cases.

Conclusion:

Small bowel capsule endoscopy is safe and effective in the investigation of left ventricular assist device associated suspected small bowel bleeding.

Evaluation of Gastric Disease with Capsule Endoscopy

The clinical indication for capsule endoscopy has expanded from small bowel evaluation to include esophagus or colon evaluation.Nevertheless, the role of capsule endoscopy in evaluation of the stomach is very limited because of the large volume and surface.However, efforts to develop an active locomotion system for capsule manipulation in detailed gastric evaluation are ongoing, becausethe technique is non-invasive, convenient, and safe, and requires no sedation. Studies have successfully reported gastric evaluation usinga magnetic-controlled capsule endoscopy system. Advances in technology suggest that capsule endoscopy will have a major role notonly in the evaluation of gastric disorders but also in the pathologic diagnosis, intervention, and treatment of any gastrointestinal tractdisorder.

What defines quality in small bowel capsule endoscopy

Small bowel capsule endoscopy is considered a first-line diagnostic tool for the investigation of small bowel diseases. Gastroenterological and endoscopic societies have proposed and established measures known as quality indicators, quality measures or performance measures for the majority of endoscopic procedures, in order to ensure competence, healthcare quality and define areas requiring improvement. However, there is a paucity of publications describing small bowel capsule endoscopy quality indicators. Hereby, we attempt to identify and describe a number of pre-procedure, intra-procedure and post-procedure quality indicators, regarding process measures in small bowel capsule endoscopy, after a comprehensive review of the literature.

A Small Bowel Ulcer due to Clopidogrel with Cytomegalovirus Enteritis Diagnosed by Capsule and Double-Balloon Endoscopy

We report the first case of small bowel ulcers due to clopidogrel in a 74-year-old man. He presented with diarrhea and melena after having been taking low-dose aspirin (LDA) and clopidogrel. There was no evidence of bleeding in the stomach, duodenum, or colon. Capsule endoscopy showed multiple ulcers and erosions in the small intestine. Double-balloon endoscopy revealed multiple ulcers throughout the ileum. Examination of the biopsy specimen showed cytomegalovirus infection. His LDA was discontinued and he was prescribed ganciclovir. However, the small bowel ulcers were aggravated. Therefore, clopidogrel was discontinued. The small bowel ulcers subsequently healed completely, forming scars.

Emerging optical methods for endoscopic surveillance of Barrett's oesophagus

Barrett's oesophagus is an acquired metaplastic condition that predisposes patients to the development of oesophageal adenocarcinoma, prompting the use of surveillance regimes to detect early malignancy for endoscopic therapy with curative intent. The currently accepted surveillance regime uses white light endoscopy together with random biopsies, but has poor sensitivity and discards information from numerous light-tissue interactions that could be exploited to probe structural, functional, and molecular changes in the tissue. Advanced optical methods are now emerging that are highly sensitive to these changes and hold potential to improve surveillance of Barrett's oesophagus if they can be applied endoscopically. The next decade will see some of these exciting new methods applied to surveillance of Barrett's oesophagus in new device architectures for the first time, potentially leading to a long-awaited improvement in the standard of care.

Sham Feeding with Bacon Does Not Alter Transit Time or Complete Examination Rate During Small Bowel Capsule Endoscopy

BACKGROUND

During capsule endoscopy (CE) studies, the complete examination rate (CER) can be increased by prolonging capsule battery life or reducing gastric transit time (GTT) and/or small bowel transit time (SBTT). However, despite enhanced battery life, 10% of studies remain incomplete. Previously studied interventions to reduce SBTT and enhance CER have produced conflicting results. We hypothesize that this may be a consequence of an insufficiently potent stimulus of small bowel motility.

AIMS

To examine whether potent stimulation of the cephalic response of digestion during small bowel CE reduces GTT and/or SBTT and thus increases the CER.

METHODS

A single-blind randomized trial was performed to evaluate the effect of bacon sham feeding on GTT, SBTT and CER.

RESULTS

Baseline characteristics were similar between 63 sham fed patients and 59 controls. The median GTT was 17 min (9-65) in the bacon group and 25 min (14-55) in the control group. The median SBTT was 199 min (119-316) and 222 min (151-287), respectively. Cox proportional hazards model demonstrated no significant difference between groups for GTT (rate ratio 1.03, 95% CI 0.71-1.51, P = 0.87) or SBTT (rate ratio 1.02, 95% CI 0.70-1.49, P = 0.93). Although the taste of bacon was considered favorably by 72% of participants, taste did not correlate with GTT (ρ = 0.03, P = 0.83) or SBTT (ρ = - 0.115, P = 0.33). The CER was 91 and 95% in the bacon and control groups, respectively (P = 0.35).

CONCLUSION

Bacon sham feeding has no effect on GTT, SBTT or CER and cannot be recommended in clinical practice.

In Vivo Characterization of a Wireless Telemetry Module for a Capsule Endoscopy System Utilizing a Conformal Antenna

This paper describes the design, fabrication, packaging, and performance characterization of a conformal helix antenna created on the outside of a capsule endoscope designed to operate at a carrier frequency of 433 MHz within human tissue. Wireless data transfer was established between the integrated capsule system and an external receiver. The telemetry system was tested within a tissue phantom and in vivo porcine models. Two different types of transmission modes were tested. The first mode, replicating normal operating conditions, used data packets at a steady power level of 0 dBm, while the capsule was being withdrawn at a steady rate from the small intestine. The second mode, replicating the worst-case clinical scenario of capsule retention within the small bowel, sent data with stepwise increasing power levels of -10, 0, 6, and 10 dBm, with the capsule fixed in position. The temperature of the tissue surrounding the external antenna was monitored at all times using thermistors embedded within the capsule shell to observe potential safety issues. The recorded data showed, for both modes of operation, a low error transmission of 10^-3 packet error rate and 10^-5 bit error rate and no temperature increase of the tissue according to IEEE standards.

Can we rely on inflammatory biomarkers for the diagnosis and monitoring Crohn's disease activity?

BACKGROUND

Small bowel capsule endoscopy (SBCE) is a very important tool in the diagnosis and monitoring of Crohn's disease (CD). The Lewis score (LS) and Capsule Endoscopy Crohn's Disease Activity Index (CECDAI) are used to quantify and standardize inflammatory activity observed in the SBCE.

AIM

To evaluate the correlation between the LS and CECDAI scores and inflammation biomarkers (C-reactive protein [CRP] and erythrocyte sedimentation rate [ESR]). A secondary goal was to define thresholds for CECDAI based on thresholds already established for LS.

METHODS

This was a retrospective study of 110 patients with suspect or known CD, with involvement of small bowel. Linear regression was used to calculate thresholds of CECDAI corresponding to the thresholds already established for LS. A Pearson correlation (r) was used to calculate the correlation between the LS and CECDAI scores and biomarker levels. Only patients with exclusive involvement of the small bowel were selected (n = 78).

RESULTS

A moderate correlation was found between the endoscopic scores (r = 0.59, p < 0.001). CECDAI scores of 5.57 and 7.53 corresponded to scores of 135 and 790 in LS, respectively. There was a statistically significant correlation between CRP and the LS (r = 0.28, p = 0.014) and CECDAI (r = 0.29, p = 0.009). There was also a significant correlation between ESR and CECDAI (r = 0.29, p = 0.019), but not with LS.

CONCLUSION

There is a moderate correlation between the two scores. This study allowed the calculation of thresholds for CECDAI based on those defined for LS. We found a weak correlation between SBCE endoscopic activity and inflammatory biomarkers.

An innovative robotic platform for magnetically-driven painless colonoscopy

Colorectal cancer (CRC) represents a significant medical threat with a dramatic impact on the healthcare system with around 1.3 million patients worldwide, causing more than 700 thousand deaths annually. A key-aspect to successful and cost-effective disease management is represented by the early detection of CRC at asymptomatic stage. For this reason, population screening is highly recommended for patients older than 50 years or at high risk for familiarity. Currently, the standard endoscopic techniques do not meet this need. In recent years, innovative endoscopic robotic techniques and active locomotion devices have been developed as alternatives to conventional colonoscopy. The magnetically-driven robotic platform, presented by the authors, is conceived to perform less invasive and more comfortable colonoscopy with the aim to promote screening campaigns for detection of early colorectal neoplasm.

Role of esophagogastroduodenoscopy in detecting distal duodenal lesions: A single-center pilot study in Southern China

OBJECTIVE

Esophagogastroduodenoscopy (EGD) is a standard instrument for detecting upper gastrointestinal lesions. However, the distal duodenum is often missed. This study aimed to clarify the diagnostic role of EGD in the distal duodenum.

METHODS

This retrospective study enrolled patients with distal duodenal lesions who underwent EGD between January 2004 and July 2016 at our center. The rate of missed diagnosis using EGD examination was calculated. Logistic regression analysis was performed to identify the factors associated with the missed diagnoses.

RESULTS

Sixty-three patients were included in the study. The overall diagnostic rate of distal duodenal lesions on EGD was 58.7%. After excluding the patients in whom the EGD did not reach the distal duodenum, this rate rose to 82.2%. In univariate analysis, intravenous sedation (26.8% vs 68.2%, odds ratio [OR] 0.171, P = 0.002), signs of lesions adjacent to the stomach (19.4% vs 62.5%, OR 0.099, P = 0.001), prior enteroscopy experience (15.0% vs 87.0%, OR 0.026, P < 0.001), and endoscopists with experiences of over 10 years (13.8% vs 64.7%, OR 0.087, P = 0.000) were associated with a decreased risk of missed diagnosis. In multivariate analysis, signs of lesions adjacent to the stomach (OR 0.167, P = 0.039) and prior enteroscopy experience (OR 0.035, P < 0.001) were significant independent protective factors.

CONCLUSION

EGD may be important in diagnosing distal duodenal lesions. Patients with gastric retention, blood in the stomach or erosion in the proximal duodenum may benefit from the deep insertion of EGD.

A global perspective on capsule endoscopy

A search of the internet today to quantify the estimated value of capsules from a global perspective, easily delivers figures stating around $200 million in 2014 to about $400 million by 2020, which would be approximately 10% of the gastrointestinal endoscopic market. Is this a steep rise within just six years or could the capsule market do even better? What chances does this offer and what are the key aspects for future success? By 2020, more than 1 billion people are aged sixty or older and around one third of them will live in what the UN calls "more developed regions". Naturally, this brings an increased demand for colorectal cancer screening and surgery. But keeping in mind that basically every healthcare system, in any country, is already operating at its limits, how do we secure future treatment for a growing community? Surely more competition will steadily bring down prices for capsules. However, that does not ease the amount of time that is spent to properly read any video and issue a valid diagnosis for every patient. This article intends to give an overview about the current global market for capsule endoscopy (CE) with a perspective on typical patients, their indications, and how the capsules are used and by whom. Further aspects, such as standardization of training, reading and future trends will also be elaborated on.

Practice patterns and clinical significance of use of capsule endoscopy in suspected and established Crohn's disease

Background/Aims

Although the role of capsule endoscopy (CE) in Crohn's disease (CD) has expanded, CE is not used routinely for diagnosing and evaluating CD in Korea. We aimed to investigate current patterns of practice and evaluate the clinical significance of the use of CE in CD in Korean patients.

Methods

Among 651 CE procedures performed for various indications, we retrospectively analyzed the medical records of patients who underwent CE in 57 cases of suspected CD (sCD) and 14 cases of established CD (eCD).

Results

In the sCD group, CE was most commonly used for the initial diagnosis of CD (54.4%). Capsule retention was found in only 1 patient in the eCD group (1/71, 1.4%). In the sCD group, 28.1% of patients were diagnosed with CD on the basis of CE findings; other diseases diagnosed included tuberculous enteritis (7.0%), non-steroidal anti-inflammatory drug-induced enteropathy (5.3%), and other enteritis (17.5%). Only 11.5% of patients with eCD (14/122) underwent CE. The indication for CE in the 14 patients with eCD was to assess disease extent and activity. The overall diagnostic yield of CE was 59.7%. Therapeutic strategies were changed in 70.2% of patients in the sCD group and 50% of those in the eCD group based on CE findings.

Conclusions

In clinical practice, CE was most commonly indicated for the initial diagnosis of CD and was not generally performed in patients with eCD. CE appears to be an effective diagnostic modality for evaluating sCD and is useful for determining therapeutic strategies for patients with sCD and those with eCD.

Validation of the computed assessment of cleansing score with the Mirocam® system

BACKGROUND AND AIMS

A computed assessment of cleansing (CAC) score was developed to objectively evaluate small-bowel cleansing in the PillCam® capsule endoscopy (CE) system and to overcome the subjectivity and complexity of previous scoring systems. Our study aimed to adapt the CAC score to the Mirocam® system, evaluate its reliability with the Mirocam® CE system and compare it with three validated subjective grading scales.

PATIENTS AND METHODS

Thirty CE were prospectively and independently reviewed by two authors who classified the degree of small-bowel cleanliness according to a quantitative index, a qualitative evaluation and an overall adequacy assessment. The authors were blinded for the CAC score of each CE, which was calculated as ([mean intensity of the red channel]/[mean intensity of the green channel] - 1) x 10. The mean intensities of the red and green channels of the small-bowel segment of the "Map View" bar in the Miroview Client® were determined using the histogram option of two photo-editing software.

RESULTS

There was a strong agreement between both CE readers for each of the three subjective scales used. The reproducibility of the CAC score was excellent and identical results were obtained with the two photo-editing software. Regarding the comparison between the CAC score and the subjective scales, there was a moderate-to-good agreement with the quantitative index, qualitative evaluation and overall adequacy assessment.

CONCLUSIONS

CAC score represents an objective and feasible score in the assessment of small-bowel cleansing in the Mirocam® CE system, and could be used per se or as part of a more comprehensive score.

Development of a Mechanical Scanning Device With High-Frequency Ultrasound Transducer for Ultrasonic Capsule Endoscopy

Wireless capsule endoscopy has opened a new era by enabling remote diagnostic assessment of the gastrointestinal tract in a painless procedure. Video capsule endoscopy is currently commercially available worldwide. However, it is limited to visualization of superficial tissue. Ultrasound (US) imaging is a complementary solution as it is capable of acquiring transmural information from the tissue wall. This paper presents a mechanical scanning device incorporating a high-frequency transducer specifically as a proof of concept for US capsule endoscopy (USCE), providing information that may usefully assist future research. A rotary solenoid-coil-based motor was employed to rotate the US transducer with sectional electronic control. A set of gears was used to convert the sectional rotation to circular rotation. A single-element focused US transducer with 39-MHz center frequency was used for high-resolution US imaging, connected to an imaging platform for pulse generation and image processing. Key parameters of US imaging for USCE applications were evaluated. Wire phantom imaging and tissue phantom imaging have been conducted to evaluate the performance of the proposed method. A porcine small intestine specimen was also used for imaging evaluation in vitro. Test results demonstrate that the proposed device and rotation mechanism are able to offer good image resolution ( [Formula: see text]) of the lumen wall, and they, therefore, offer a viable basis for the fabrication of a USCE device.

Acoustic Sensing and Ultrasonic Drug Delivery in Multimodal Theranostic Capsule Endoscopy

Video capsule endoscopy (VCE) is now a clinically accepted diagnostic modality in which miniaturized technology, an on-board power supply and wireless telemetry stand as technological foundations for other capsule endoscopy (CE) devices. However, VCE does not provide therapeutic functionality, and research towards therapeutic CE (TCE) has been limited. In this paper, a route towards viable TCE is proposed, based on multiple CE devices including important acoustic sensing and drug delivery components. In this approach, an initial multimodal diagnostic device with high-frequency quantitative microultrasound that complements video imaging allows surface and subsurface visualization and computer-assisted diagnosis. Using focused ultrasound (US) to mark sites of pathology with exogenous fluorescent agents permits follow-up with another device to provide therapy. This is based on an US-mediated targeted drug delivery system with fluorescence imaging guidance. An additional device may then be utilized for treatment verification and monitoring, exploiting the minimally invasive nature of CE. While such a theranostic patient pathway for gastrointestinal treatment is presently incomplete, the description in this paper of previous research and work under way to realize further components for the proposed pathway suggests it is feasible and provides a framework around which to structure further work.

Clinical Practice Guideline for Enteroscopy

Management of small bowel diseases has evolved since the advent of capsule endoscopy (CE) and balloon-assisted enteroscopy (BAE). One of the most common indications for enteroscopy is obscure gastrointestinal bleeding (OGIB), followed by small bowel stenosis, tumors, and inflammatory bowel disease. Although enteroscopes have been regarded as useful tools, correct guidelines are required to ensure that we manipulate these enteroscopes safely and efficiently in clinical practice. Herein, the Japanese Gastroenterological Endoscopy Society has developed 'Clinical Practice Guidelines for Enteroscopy' in collaboration with the Japanese Society of Gastroenterology, the Japanese Gastroenterological Association, and the Japanese Association for Capsule Endoscopy. These guidelines are based on the evidence available until now, but small bowel endoscopy is a relatively new technology, so the guidelines include recommendations based on a consensus reached among experts when the evidence has not been considered sufficient. These guidelines were not designed to be disease-based, but focus on how we should use small bowel CE and BAE in everyday clinical practice.

International core curriculum for capsule endoscopy training courses

Capsule endoscopy (CE) has become a first-line noninvasive tool for visualisation of the small bowel (SB) and is being increasingly used for investigation of the colon. The European Society of Gastrointestinal Endoscopy (ESGE) guidelines have specified requirements for the clinical applications of CE. However, there are no standardized recommendations yet for CE training courses in Europe. The following suggestions in this curriculum are based on the experience of European CE training courses directors. It is suggested that 12 hours be dedicated for either a small bowel capsule endoscopy (SBCE) or a colon capsule endoscopy (CCE) course with 4 hours for an introductory CCE course delivered in conjunction with SBCE courses. SBCE courses should include state-of-the-art lectures on indications, contraindications, complications, patient management and hardware and software use. Procedural issues require approximately 2 hours. For CCE courses 2.5 hours for theoretical lessons and 3.5 hours for procedural issued are considered appropriate. Hands-on training on reading and interpretation of CE cases using a personal computer (PC) for 1 or 2 delegates is recommended for both SBCE and CCE courses. A total of 6 hours hands-on session- time should be allocated. Cases in a SBCE course should cover SB bleeding, inflammatory bowel diseases (IBD), tumors and variants of normal and cases with various types of polyps covered in CCE courses. Standardization of the description of findings and generation of high-quality reports should be essential parts of the training. Courses should be followed by an assessment of trainees' skills in order to certify readers' competency.

The impact of hospitalization on the performance of capsule endoscopy (CE)

BACKGROUND

For proper evaluation of capsule endoscopy (CE), a complete examination is necessary.

AIM

We evaluated risk factors of an incomplete CE with focus on patient hospitalization.

METHODS

We retrospectively evaluated 161 consecutive patients who underwent CE between 01.07.2013 and 13.03.2016. Main indications were active bleeding, iron deficiency anemia (IDA), inflammatory bowel disease (IBD), abdominal pain, and familial adenomatous polyposis (FAP).

RESULTS

We report the results of 103 in-patients and 56 out-patients. Eighty-two patients were male, average age was 58.9 years (range 18-90). Indications for CE were active bleeding (103 patients), IDA and IBD (16 patients), and FAP, abdominal pain and others (eight examinations each). All FAP patients were out-patients, but showed the longest small bowel transit time (SBTT) of 443.6min (p=0.0001). The shortest SBTT was found in out-patients without FAP (267.5min, p<0.05). In the in-patient group, nine endoscopies did not record the entire small bowel (8.7%) due to battery depletion, compared with only one incomplete examination in the out-patients (1.8%, p=0.036). We found pathologic lesions in the last 30min of the SBTT in 43 patients, and this indicates the necessity for complete examination. Thirteen of these 43 patients showed major lesions such as ulcers or angiodysplasia in this last region alone.

CONCLUSION

In-patients might require special treatment to ensure complete examination, since a considerable amount of pathologies can only be found in the ileum.

WITHDRAWN: The Role of capsule endoscopy and device assisted enteroscopy for small bowel lesions in hereditary hemorrhagic telangiectasia

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Multiaccess In Vivo Biotelemetry Using Sonomicrometry and M-Scan Ultrasound Imaging

Objective: In this paper, we investigate the use of commercial off-the-shelf diagnostic ultrasound readers to achieve multiaccess wireless in vivo telemetry with millimeter-sized sonomicrometry crystal transducers.

METHODS

The sonomicrometry crystals generate ultrasonic pulses that supersede the echoes generated at the tissue interfaces in response to M-scan interrogation pulses. The traces of these synthetic pulses are captured on an M-scan image and the transmitted data are decoded using image deconvolution and deblurring algorithms.

RESULTS

Using a chicken phantom and 1.3 MHz sonomicrometry crystals of diameter 1 mm, we first demonstrate that a standard ultrasound reader can achieve biotelemetry data rates up to 1 Mb/s for implantation depths greater than 10 cm. For this experiment the maximum power dissipation at the crystals was measured to be 20 and bit-error-rate of the telemetry link was shown to be . We also demonstrate the use of this method for multiaccess biotelemetry where several sonomicrometry crystals simultaneously transmit the data using different modulation and coding techniques. Using a live ovine model, we demonstrate a sonomicrometry crystal implanted in the sheep 's tricuspid valve can maintain a continuous, reliable telemetry link at data rates up tob 800 Kb/s in the presence of respiratory and cardiac motion artifacts.

CONCLUSION

Compared to existing radio-frequency and ultrasound based biotelemetry devices, the reported data-rates are significantly higher considering the transducer's form-factor and its implantation depth.

SIGNIFICANCE

The proposed technique thus validates the feasibility of establishing reliable communication link with multiple in vivo implants using M-scan-based ultrasound imaging.

A comprehensive evaluation of the gastrointestinal tract in iron-deficiency anemia with predefined hemoglobin below 9mg/dL: A prospective cohort study

BACKGROUND

Anemia is defined as hemoglobin below the cutoff of normal in studies examining the gastrointestinal (GI) tract in iron-deficiency anemia (IDA). Although the risk of GI cancer (GIC) increases as hemoglobin decreases, guidelines do not usually recommend hemoglobin thresholds for IDA investigation.

METHODS

To elucidate whether underlying GI disorders explain the different hemoglobin values and clinical outcomes observed initially in IDA patients referred for GI workup, we prospectively investigated the diagnostic yield of a thorough GI examination in consecutive IDA adults with predefined hemoglobin <9g/dL and no extraintestinal bleeding.

RESULTS

4552 patients were enrolled over 10 years. 96% of 4038 GI lesions were consistent with occult bleeding disorders and 4% with non-bleeding disorders. Predominant bleeding disorders included upper GI ulcerative/erosive lesions (51%), GIC (15%), and angiodysplasias (12%). Diffuse angiodysplasias (45% of angiodysplasias) and GIC showed the lowest hemoglobin values (6.3 [1.5] and 6.4 [1.3]g/dL, respectively). While the spread (diffuse vs. localized) and number (<3 vs. ≥3) of angiodysplasias correlated with the degree of anemia, hemoglobin values were lower in GIC with vs. without ulcerated/friable lesions (6.0 [1.1] vs. 7.0 [1.2]g/dL, P<0.001).

CONCLUSION

Not only GIC but also diffuse angiodysplasias caused the most severe anemia in IDA with predefined hemoglobin values <9g/dL.

NASPGHAN Capsule Endoscopy Clinical Report

Wireless capsule endoscopy (CE) was introduced in 2000 as a less invasive method to visualize the distal small bowel in adults. Because this technology has advanced it has been adapted for use in pediatric gastroenterology. Several studies have described its clinical use, utility, and various training methods but pediatric literature regarding CE is limited. This clinical report developed by the Endoscopic and Procedures Committee of the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition outlines the current literature, and describes the recommended current role, use, training, and future areas of research for CE in pediatrics.

Use of Wireless Capsule Endoscopy for the Diagnosis and Grading of Esophageal Varices in Patients With Portal Hypertension: A Systematic Review and Meta-Analysis

INTRODUCTION

Esophageal variceal bleeding is a severe complication of portal hypertension with significant morbidity and mortality. Although traditional screening and grading of esophageal varices has been performed by endogastroduodenoscopy (EGD), wireless video capsule endoscopy provides a minimally invasive alternative that may improve screening and surveillance compliance.

AIM OF THE STUDY

The aim of the study was to perform a systematic review and structured meta-analysis of all eligible studies to evaluate the efficacy of wireless capsule endoscopy for screening and diagnosis of esophageal varices among patients with portal hypertension.

METHODS

Searches of PubMed, EMBASE, Web of Science, and the Cochrane Library databases were performed through December 2015. Bivariate and hierarchical models were used to compute the pooled sensitivity and specificity, and to plot the summary receiver operating characteristics curve with summary point and corresponding 95% confidence region. Bias of included studies was assessed using the quality assessment of diagnostic accuracy studies-2.

RESULTS

Seventeen studies from 2005 to 2015 were included in this meta-analysis (n=1328). The diagnostic accuracy of wireless capsule endoscopy in the diagnosis of esophageal varices was 90% [95% confidence interval (CI), 0.88-0.93]. The diagnostic pooled sensitivity and specificity were 83% (95% CI, 0.76-0.89) and 85% (95% CI, 0.75-0.91), respectively. The diagnostic accuracy of wireless capsule endoscopy for the grading of medium to large varices was 92% (95% CI, 0.90-0.94). The pooled sensitivity and specificity were 72% (95% CI, 0.54-0.85) and 91% (95% CI, 0.86-0.94), respectively, for the grading of medium to large varices. The use of capsule demonstrated only mild adverse events. A sensitivity analysis limited to only high quality studies revealed similar results.

DISCUSSION

Wireless esophageal capsule endoscopy is well tolerated and safe in patients with liver cirrhosis and suspicion of portal hypertension. The sensitivity of capsule endoscopy is not currently sufficient to replace EGD as a first exploration in these patients, but given its high accuracy, it may have a role in cases of refusal or contraindication to EGD.

Colon capsule endoscopy: toward the future

Colon capsule endoscopy is a wireless and minimally invasive technique for visualization of the whole colon. With recent improvements of technical features in second-generation systems, a more important role for colon capsule endoscopy is rapidly emerging. Although several limitations and drawbacks are yet to be resolved, its usefulness as a tool for colorectal cancer screening and monitoring disease activity in inflammatory bowel diseases has become more apparent with increased use. Further investigations, including multicenter trials, are required to evaluate the substantial role of the colon capsule in managing colorectal diseases.

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.

Role of capsule endoscopy in suspected celiac disease: A European multi-centre study

AIM

To analyze the diagnostic yield (DY), therapeutic impact (TI) and safety of capsule endoscopy (CE).

METHODS

This is a multi-centre, observational, analytical, retrospective study. A total of 163 patients with suspicion of celiac disease (CD) (mean age = 46.4 ± 17.3 years, 68.1% women) who underwent CE from 2003 to 2015 were included. Patients were divided into four groups: seronegative CD with atrophy (Group-I, n = 19), seropositive CD without atrophy (Group-II, n = 39), contraindication to gastroscopy (Group-III, n = 6), seronegative CD without atrophy, but with a compatible context (Group-IV, n = 99). DY, TI and the safety of CE were analysed.

RESULTS

The overall DY was 54% and the final diagnosis was villous atrophy (n = 65, 39.9%), complicated CD (n = 12, 7.4%) and other enteropathies (n = 11, 6.8%; 8 Crohn's). DY for groups I to IV was 73.7%, 69.2%, 50% and 44.4%, respectively. Atrophy was located in duodenum in 24 cases (36.9%), diffuse in 19 (29.2%), jejunal in 11 (16.9%), and patchy in 10 cases (15.4%). Factors associated with a greater DY were positive serology (68.3% vs 49.2%, P = 0.034) and older age (P = 0.008). On the other hand, neither sex nor clinical presentation, family background, positive histology or HLA status were associated with DY. CE results changed the therapeutic approach in 71.8% of the cases. Atrophy was associated with a greater TI (92.3% vs 45.3%, P < 0.001) and 81.9% of the patients responded to diet. There was one case of capsule retention (0.6%). Agreement between CE findings and subsequent histology was 100% for diagnosing normal/other conditions, 70% for suspected CD and 50% for complicated CD.

CONCLUSION

CE has a high DY in cases of suspicion of CD and it leads to changes in the clinical course of the disease. CE is safe procedure with a high degree of concordance with histology and it helps in the differential diagnosis of CD.

Fecal occult blood testing for the prediction of small-bowel pathology detected by capsule endoscopy: a systematic review and meta-analysis

Background

Fecal occult blood testing (FOBT) has been suggested as a potential screening tool for small-bowel capsule endoscopy (CE). We conducted a meta-analysis of studies correlating FOBT and CE findings to examine the predictive value of positive FOBT for CE findings.

Methods

PubMed and Embase search. Sensitivity, specificity and diagnostic odds ratios (DORs) were calculated.

Results

Six studies were identified. Four used fecal immunochemical testing (FIT), one used FIT and guaiac FOBT, one used hemoglobin/haptoglobin complex testing (Hb/Hpt). Five of the 6 studies were suitable for statistical analysis. For all positive FOBT, sensitivity for small-bowel findings was 0.60 (95%CI 0.50-0.69), specificity was 0.72 (95%CI 0.52-0.86), and DOR was 3.96 (95%CI 1.50-10.4). For the 4 studies using only FIT, sensitivity was 0.48 (95%CI 0.36-0.61), specificity was 0.60 (95%CI 0.42-0.76), and DOR was 1.41 (95%CI 0.72-2.75).

Conclusions

Although a number of modalities have been suggested for screening small-bowel CE referrals, none of them, including FOBT, offer a comprehensive solution. Further work is required to refine screening methods for small-bowel CE referrals.

Suspected blood indicator in capsule endoscopy: a valuable tool for gastrointestinal bleeding diagnosis

BACKGROUND

Small bowel bleeding is a leading indication for small bowel capsule endoscopy. The Suspected Blood Indicator (SBI) is a software feature directed to automatically detect bleeding lesions during small bowel capsule endoscopy.

OBJECTIVE

- We aimed to assess SBI diagnostic accuracy for small bowel haemorrhage or potentially bleeding lesions during small bowel capsule endoscopy for small bowel bleeding. Methods - Single-centre retrospective study including 281 consecutive small bowel capsule endoscopy performed for small bowel bleeding during 6 years. The investigators marked lesions with high bleeding potential (P2), such as angioectasias, ulcers and tumours, as well as active bleeding during regular small bowel capsule endoscopy viewing with PillCam SB2(r). All small bowel capsule endoscopy were independently reviewed by another central reader using SBI.

RESULTS

- Among the 281 patients, 29 (10.3%) presented with active haemorrhage while 81 (28.9%) presented with a P2 lesion. The most frequently observed P2 lesions were angioectasias (52), ulcers (15), polyps (7) and ulcerated neoplasias (7). SBI showed a 96.6% (28/29) sensitivity for active small bowel bleeding, with a 97.7% negative predictive value. Regarding P2 lesions, the SBI displayed an overall sensitivity of 39.5%, being highest for ulcerated neoplasias (100%), but significantly lower for angioectasias (38.5%) or ulcers (20.0%).

CONCLUSION

Although SBI sensitivity for the automatic detection of potentially bleeding lesions was low, it effectively detected active small bowel bleeding with very high sensitivity and negative predictive value.

The validity of suspected blood indicator software in capsule endoscopy: a systematic review and meta-analysis

Software tools have been developed as capsule endoscopy (CE) reading aids. The suspected blood indicator (SBI) tags possible areas of haemorrhage in the gastrointestinal (GI) tract. This meta-analysis aims to investigate the diagnostic accuracy of SBI in CE. Areas covered: A systematic literature search was conducted for studies on the use of SBI in CE. Sensitivity, specificity and diagnostic odds ratio (DOR) of SBI in diagnosing GI bleeding was evaluated. 2040 patients from 16 studies underwent 2049 CE examinations. The overall sensitivity of SBI for bleeding or potentially bleeding lesions was 0.553, specificity 0.578, DOR 12.354. The sensitivity of SBI for active bleeding was 0.988, specificity 0.646, DOR 229.89. Expert commentary: Currently, SBI has limited validity in CE reading. However, in active GI bleeding, it has good sensitivity, supporting its use in the acute setting.

Obscure Overt Gastrointestinal Bleeding Secondary to Ventral Hernioplasty Mesh Small Bowel Perforation Visualized With Video Capsule Endoscopy

We report a case of a 79-year-old female presenting with hematemesis and melena 9 years after ventral hernioplasty with mesh. After initial normal endoscopy and colonoscopy, video capsule endoscopy revealed a metallic wire mesh perforating the jejunum. Abdominal computed tomography did not identify a perforation although metallic mesh was visualized close to the small bowel. We present the first ventral hernia mesh perforation diagnosed via video capsule endoscopy. Such a finding emphasizes the importance of a complete diagnostic workup when approaching a patient with obscure overt gastrointestinal bleeding.

Capsule endoscopy for the diagnosis and follow up of Crohn's disease: a comprehensive review of current status

Capsule endoscopy (CE) has revolutionized the diagnosis and monitoring of small bowel Crohn’s disease (CD). The procedure is patient friendly and noninvasive, and compared to cross-sectional imaging, CE allows a direct and detailed evaluation of the entire small bowel mucosa with a high sensitivity for the earliest lesions of CD. Today, CE is the leading modality for visualizing the small bowel in suspected CD, and validated activity indices are available for the follow up of patients with established CD. CE of the entire gastrointestinal tract (panenteric CE) was recently introduced as a new diagnostic approach in patients examined for CD, and preliminary results are promising. There are important limitations, involving mainly capsule retention. Furthermore, a diagnostic criterion for CD has never been validated, and lesions detected by CE are not specific for CD. Hence, concern has been raised about a low specificity compared to other diagnostic modalities. Important questions about the optimal bowel preparation, selection of patients for CE and the optimal reading protocol remain to be clarified. The aim of this review is to evaluate the performance of CE for diagnosing CD and assess disease activity in known CD; to compare the diagnostic accuracy of CE to that of cross-sectional imaging; to discuss limitations; and to define the place of CE in the diagnostic algorithm in suspected or known CD.

Contraindications for video capsule endoscopy

Video capsule endoscopy (VCE) has been applied in the last 15 years in an increasing field of applications. Although many contraindications have been put into perspective, some precautions still have to be considered. Known stenosis of the gastrointestinal tract is a clear contraindication for VCE unless surgery is already scheduled or at least has been considered as an optional treatment modality. In patients with a higher incidence of stenosis, as in an established diagnosis of Crohn’s disease, clinical signs of obstruction, prior radiation or surgical small bowel resection, a preceding test with the self-dissolving patency capsule can override this contraindication. Endoscopic placement of the capsule should be considered in patients with swallowing disorders to avoid aspiration. Esophageal or gastric motility disorders may require endoscopic capsule transport or application of prokinetics if the real-time viewer proofs delayed transit. In pregnant women, VCE should be restricted to urgent cases where diagnosis cannot be postponed after delivery, as data on safety are missing. There is theoretical and clinical evidence that patients with implanted cardiac devices such as a pacemaker, cardioverters or left heart assist devices, can safely undergo VCE in spite of still existing contraindication by manufacturers. Children from the age of 2 years have safely undergone VCE. Although video capsules are not proven safe with magnetic resonance imaging (MRI), first single cases of patients incidentally undergoing MRI with an incorporated capsule have been reported, showing susceptibility artifacts but no signs of clinical harm.

Initial Experience of Video Capsule Endoscopy After Intestinal Transplantation

BACKGROUND

Intestinal transplantation is a procedure which inflicts immunological and infectious complications that affect the transplanted graft, posing both diagnostic and therapeutic challenges. Video capsule endoscopy (VCE) offers easy access to the entire small intestine and presents itself as an interesting option. However, at present, no studies evaluating the usefulness of video capsule endoscopies in this setting have been published. Our aim was to evaluate the usefulness of VCE in detecting complications that arise after intestinal transplantation.

METHODS

We included 7 adult patients with either isolated intestine (n = 1) or multivisceral grafts (n = 6). These patients underwent 12 VCE between 2004 and 2015 at the Sahlgrenska University Hospital. The median age was 42 (21-67) years (4 women/3 men). VCE was used in clinical situations where the conventional diagnostic methods failed to provide answers to the clinical question.

RESULTS

Indications for the procedure were: suspicion of rejection (n = 4 examinations), gastrointestinal dysmotility (n = 4 examinations), high stomal output (n = 2 examinations), suspicion of lymphoproliferative disease in the transplanted graft (n = 1 examination), and clinical surveillance (n = 1 examination). The median time after transplantation for performing an examination was 740 (26-3059) days. VCE was useful in 83% of the examinations and the results influenced the planned management. The overall agreement between VCE findings and biopsies was moderate (κ = 0.54, P = 0.05) but increased when comparing the presence of inflammation/rejection (κ = 0.79, P < 0.001).

CONCLUSIONS

VCE is a promising diagnostic method after intestinal transplantation. However, larger studies are needed to evaluate its potential risks and gains.

Current role of capsule endoscopy in Crohn’s disease

Capsule endoscopy (CE) currently plays an important role in Crohn’s disease (CD). It is a noninvasive technique that has led to a breakthrough in the endoscopic diagnosis of diseases of the small intestine. Its superior diagnostic performance and excellent safety profile lead to its considerable acceptance on the part of the patient. This paper reviews current indications of CE in three stages of clinical practice: Suspected CD, unclassified colitis and its extensive role in diagnosed CD. The diagnostic and therapeutic impact of the results of CE on the monitoring of this disease is also reviewed. Knowledge of its applications, the interpretation of its results in an appropriate context and the existence of a validated endoscopic activity index could change the way in which these patients are managed. The definition of mucosal healing and postoperative recurrence by means of endoscopic scoring systems will endow CE with new applications in the management of CD in the near future.

Extraction and processing of videocapsule data to detect and measure the presence of villous atrophy in celiac disease patients

BACKGROUND

Videocapsule endoscopy is a relative new method to analyze the gastrointestinal tract for the presence of pathologic features. It is of relevance to detect villous atrophy in the small bowel, which is a defining symptom of celiac disease.

METHOD

In this tutorial, methods to extract and process videocapsule endoscopy data are elucidated. The algorithms, computer code, and paradigms to analyze image series are described in detail. The topics covered include extraction of data, analysis of texture, eigenanalysis, spectral analysis, three-dimensional projection, and estimation of motility. The basic paradigms to implement these processes are provided.

RESULTS

Examples of successful quantitative analysis implementations for selected untreated celiac disease patients with villous atrophy versus control patients with normal villi were illustrated. Based on the implementations, it was evident that celiac patients tended to have a rougher small intestinal texture as compared with control patients. From three-dimensional projection, celiac patients exhibited larger surface protrusions emanating from the small intestinal mucosa, which may represent clumps of atrophied villi. The periodicity of small intestinal contractions tends to be slower when villous atrophy is present, and the estimated degree of motility is reduced as compared with control image series. Basis image construction suggested that fissuring and mottling of the mucosal surface is predominant in untreated celiac patients, and mostly absent in controls.

CONCLUSIONS

Implementation of computerized methods, as described in this tutorial, will likely be useful for the automated detection and measurement of villous atrophy, and to map its extent along the small intestine of celiac patients.