Standing-type magnetically guided capsule endoscopy versus gastroscopy for gastric examination: multicenter blinded comparative trial

AIM

To compare feasibility and safety after gastrointestinal checkup by standing-type magnetically controlled capsule endoscopy (SMCE) and conventional gastroscopy.

METHODS

This was a prospective multicenter, blinded study that compared SMCE with gastroscopy in patients from April 2018 to July 2018. All patients first underwent SMCE and then subsequently had gastroscopy with i.v. anesthesia. We calculated the compliance rates of gastric lesion detection by SMCE using gastroscopy as the standard. Capsule retention rate, incidence of adverse events, and patient satisfaction were documented throughout the study.

RESULTS

One hundred and sixty-one patients who completed SMCE and gastroscopy were included in the analysis. Positive compliance rate among SMCE and gastroscopy was 92.0% (95% CI: 80.77%-97.78%). Negative compliance rate was 95.5% (89.80%, 98.52%). Moreover, overall compliance rate was 94.41% (89.65%, 97.41%). Sixty-four pathological outcomes were identified. Of these 64 outcomes, 50 were detected by both procedures. The gastroscopy method neglected seven findings (such as five erosions, one polyp, and one ulcer). Furthermore, SMCE also overlooked seven lesions (i.e. one erosion, two polyps, one atrophy, and three submucosal tumors). Capsule retention or related adverse events were not reported.

CONCLUSION

Standing-type magnetically controlled capsule endoscopy provides equivalent agreement with gastroscopy and may be useful for screening of gastric illnesses without any anesthesia.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Colon capsule endoscopy

There are multiple indications for luminal imaging of the colon. From assessment of known disease, to diagnosing new pathology; intra-luminal visualisation is the mainstay of gastrointestinal diagnosis. Colonoscopy and radiological imaging are currently the most frequently deployed diagnostic methods. However, both have an associated risk profile, have significant resource pressures and are not universally tolerated. Colon capsule endoscopy (CCE) offers an adjunct to these diagnostic options. In this narrative review the utility of CCE is described. Its current uses, potential benefits and future developments are also discussed.

[Feasibility and safety of magnetically guided capsule endoscopy in minors]

Objective: To clarify the feasibility and safety of magnetically guided capsule endoscopy (MGCE) in minors. Methods: A descriptive cohort study was carried out to retrospectively collect the data of minors (<18 years) who underwent MGCE in Ruijin Hospital from April 2015 to October 2018. Exclusion criteria: patients with dysphagia, obvious gastrointestinal bleeding, diagnosed or suspected gastrointestinal obstruction, or congenital gastrointestinal malformations or intestinal fistula; patients with previous bowel surgery, or in poor general condition; patients with implants; pregnant patients; patients with incomplete data or without data. A total of 218 patients, including 122 males and 96 females, with mean age of (12.0±3.1) (5-17) years and 236 times of examination were included. The capsule size of the Ankon MGCE system was 11.8 mm×27 mm, taking two pictures per second, with a viewing angle of 140 degrees. Data of gastric visualization (0% to 100%), gastric cleanliness (satisfactory cleanliness was defined as a clear display of the gastric mucosa; the effect of bubbles or mucus on the visual field was negligible, or the gastric mucosa was slightly blurred; a small amount of air bubbles or mucus affected slightly the field of view), gastric or small bowel examination time, lesion detection rate, etc. were recorded. All the patients were followed up for 2 weeks to confirm capsule excretion and to record adverse events. Results: A total of 202 patients (217 times) completed gastric examination and 112 patients (125 times) completed small bowel examination. The median gastric visualization of cardia, fundus, body, angulus, antrum and pylorus was 100%, 90% (75%,100%), 100% (80%,100%), 100%, 100%, and 100%, respectively. The cleanliness of the gastric cardia, fundus, body, angle, antrum, and pylorus was assessed to be satisfactory in 100.0%, 76.5% (153/200), 92.5% (185/200), 97.5% (195/200), 99.5% (199/200), and 100.0% of patients, respectively. In 202 patients undergoing gastric examination, the median gastric exanimation time was 10.5 (7.3, 13.9) minutes. In 112 patients undergoing small bowel examination, the median gastric transit time was 51.5 (20.6, 112.0) minutes and the median small bowel transit time was 232.4 (181.8, 321.6) minutes. The small bowel transit rate was 91.1% (102/112). The lesion detection rates of stomach, duodenum and jejunoileum were 18.8% (38/202), 8.1% (10/124) and 26.8% (30/112) respectively. No complications or adverse events occurred. Conclusion: MGCE is feasible and safe to detect both gastric cavity and small bowel in minors.

Device-assisted enteroscopy: A review of available techniques and upcoming new technologies

The advent of video capsule endoscopy into clinical routine more than 15 years ago led to a substantial change in the diagnostic approach to patients with suspected small bowel diseases, often indicating a deep enteroscopy procedure for diagnostical confirmation or endoscopic treatment. Device assisted enteroscopy was developed in 2001 and for the first time established a practicable, safe and effective method for evaluation of the small bowel. Currently with double-balloon enteroscopy, single-balloon enteroscopy and spiral enteroscopy three different platforms are available in clinical routine. Summarizing, double-balloon enteroscopy seems to offer the deepest insertion depth to the small bowel going hand in hand with the disadvantage of a longer procedural duration. Manual spiral enteroscopy seems to be a faster procedure but without reaching the depth of the DBE in currently available data. Finally, single-balloon enteroscopy seems to be the least complicated procedure to perform. Despite substantial improvements in the field of direct enteroscopy, even nowadays deep endoscopic access to the small bowel with all available methods is still a complex procedure, cumbersome and time-consuming and requires high endoscopic skills. This review will give an overview of the currently available techniques and will further discuss the role of the upcoming new technology of the motorized spiral enteroscopy (PowerSpiral).

Endoscopy in inflammatory bowel disease: Role in diagnosis, management, and treatment

Endoscopy plays a fundamental role in the diagnosis, management, and treatment of inflammatory bowel disease (IBD). Colonoscopy, flexible sigmoidoscopy, and esophagogastroduodenoscopy have long been used in the care of patients with IBD. As endoscopic technologies have progressed, tools such as endoscopic ultrasound, capsule endoscopy, and balloon-assisted enteroscopy have expanded the role of endoscopy in IBD. Furthermore, chromoendoscopy has enhanced our ability to detect dysplasia in IBD. In this review article, we will focus on the roles, indications, and limitations of these tools in IBD. We will also discuss the most commonly used endoscopic scoring systems, as well as special considerations in post-surgical patients. Lastly, we will discuss the role of endoscopy in the diagnosis and management of fistulae and strictures.

PillCamColon2 after incomplete colonoscopy - A prospective multicenter study

AIM

To evaluate the ability of PillCamColon2 to visualize colonic segments missed by incomplete optical colonoscopy (OC) and to assess the diagnostic yield.

METHODS

This prospective multicentre study included 81 patients from nine centres who underwent second-generation colon capsule endoscopy (CCE) following incomplete OC performed by an experienced gastroenterologist (> 1000 colonoscopies). Patients with stenosis were excluded. According to patient preferences, CCE was performed the following day (protocol A) after staying on clear liquids and 0.75 L Moviprep in the morning or within 30 d after new split-dose Moviprep (protocol B). Boosts consisted of 0.75 L and 0.25 L Moviprep, and phospho-soda was given as a rescue if the capsule was not excreted after seven hours.

RESULTS

Seventy-four patients were analysed (51% of them in group A; 49% in group B). Bowel cleansing was adequate in 67% of cases, and CCE could visualize colonic segments missed by incomplete colonoscopy in 90% of patients under protocol A and 97% of patients under protocol B (P = 0.35, n.s.). Significant polyps including adenocarcinoma were detected in 24% of cases. Detection rates for all polyps and significant polyps per patient were similar in both protocols. Polyps were found predominantly in the right colon (86%) in segments that were not reached by OC. Extracolonic findings - such as reflux esophagitis, suspected Barrett esophagus, upper GI-bleeding, gastric polyps, gastric erosions and angiectasia - were detected in eight patients. PillCamColon2 capsule was retained in the ileum of one patient (1.4%) without symptoms and removed during an uneventful resection for unknown Crohn’s disease that was diagnosed as the cause of anemia, which was the indication for colonoscopy. CCE was well tolerated. One patient suffered from self-limiting vomiting after consuming the phospho-soda.

CONCLUSION

Second-generation CCE using a low-volume preparation is useful after incomplete OC, and it allows for the detection of additional relevant findings, but cleansing efficiency could be improved.

In-Vivo Evaluation of Microultrasound and Thermometric Capsule Endoscopes

Clinical endoscopy and colonoscopy are commonly used to investigate and diagnose disorders in the upper gastrointestinal tract and colon, respectively. However, examination of the anatomically remote small bowel with conventional endoscopy is challenging. This and advances in miniaturization led to the development of video capsule endoscopy (VCE) to allow small bowel examination in a noninvasive manner. Available since 2001, current capsule endoscopes are limited to viewing the mucosal surface only due to their reliance on optical imaging. To overcome this limitation with submucosal imaging, work is under way to implement microultrasound (μUS) imaging in the same form as VCE devices. This paper describes two prototype capsules, termed Sonocap and Thermocap, which were developed respectively to assess the quality of μUS imaging and the maximum power consumption that can be tolerated for such a system. The capsules were tested in vivo in the oesophagus and small bowel of porcine models. Results are presented in the form of μUS B-scans as well as safe temperature readings observed up to 100 mW in both biological regions. These results demonstrate that acoustic coupling and μUS imaging can be achieved in vivo in the lumen of the bowel and the maximum power consumption that is possible for miniature μUS systems.

[Description of capsule endoscopy use in a pediatric public hospital]

INTRODUCTION

Capsule endoscopy (CE) is a non-invasive technique that allows visualization of small intestine mucosa. It is used for diagnosis of lesions not accessible with other tests. Our goal was to describe the experience using CE in a pediatric public hospital in Chile.

PATIENTS AND METHOD

A retrospective study was carried out to review the cases in which CE was used at Dr. Luis Calvo Mac- kenna Hospital from 2010 to date. Demographic and clinical data, findings, complications, diagnosis and treatment were recorded.

RESULTS

Twenty procedures were performed in 16 patients, 11 men (69%), median age 12 years (range 3 to 15 years). Indications included polyposis study (60%), sus pected Crohn disease (20%), obscure gastrointestinal bleeding (15%) and undiagnosed anemia (5%). Seventeen studies were altered (85%) and 11 led to a diagnosis or clinical behavior change (55%). There were no complications.

CONCLUSIONS

CE is a useful and safe technique in children, feasible to perform in a pediatric public hospital.

Applications of Colon Capsule Endoscopy

PURPOSE OF REVIEW

This is a review of colon capsule endoscopy (CCE) with a focus on its recent developments, technological improvements, and current and potential future indications.

RECENT FINDINGS

Based on the current literature, CCE II demonstrates comparable polyp detection rates as optical colonoscopy and CT colonography, and improved cost-effectiveness. The main limitation to patient acceptance is the requirement of a rigorous bowel preparation. Preliminary studies show good correlation between CCE and optical colonoscopy for assessment of colonic disease activity in inflammatory bowel disease (IBD). CCE II is currently FDA, approved as an adjunctive test in patients with prior incomplete colonoscopy, and in the evaluation of patients with suspected lower gastrointestinal bleeding. The test is approved in Europe as one of the options for average-risk colorectal cancer screening, and high-risk screening in patients with contraindications or unwilling to undergo colonoscopy. CCE has a potential role in the evaluation and monitoring of colonic disease activity in IBD. Future technological advances should focus on minimizing bowel preparation, improvement in reading times, and development of therapeutic capabilities. • With technological improvements, the second-generation colon capsule has a significantly higher sensitivity than the first-generation capsule for detection of colon polyps. • Colon capsule endoscopy has been approved in Europe as an option for average-risk colorectal cancer screening, and high-risk screening in patients with contraindications or unwilling to undergo colonoscopy. • Colon capsule endoscopy has received FDA approval as an option for colorectal cancer screening in patients with prior incomplete colonoscopy, and in evaluation of patients with suspected lower gastrointestinal bleeding. • Colon capsule endoscopy may have a role in evaluation and monitoring of inflammatory bowel disease. • Colon capsule endoscopy currently requires a bowel preparation that is more rigorous than colonoscopy.

Design and Simulation of a Ring-Shaped Linear Array for Microultrasound Capsule Endoscopy

Video capsule endoscopy (VCE) has significantly advanced visualization of the gastrointestinal tract since its introduction in the last 20 years. Work is now under way to combine VCE with microultrasound imaging. However, small maximum capsule dimensions, coupled with the electronics required to integrate ultrasound imaging capabilities, pose significant design challenges. This paper describes a simulation process for testing transducer geometries and imaging methodologies to achieve satisfactory imaging performance within the physical limitations of the capsule size and outlines many of the tradeoffs needed in the design of this new class of ultrasound capsule endoscopy (USCE) device. A hybrid MATLAB model is described, incorporating Krimholtz-Leedom-Matthaei circuit elements and digitizing and beamforming elements to render a gray-scale B-mode. This model is combined with a model of acoustic propagation to generate images of point scatterers. The models are used to demonstrate the performance of a USCE transducer configuration comprising a single, unfocused transmit ring of radius 5 mm separated into eight segments for electrical impedance control and a 512-element receive linear array, also formed into a ring. The MATLAB model includes an ultrasonic pulser circuit connected to a piezocrystal composite transmit transducer with a center frequency of 25 MHz. B-scan images are simulated for wire target phantoms, multilayered phantoms, and a gut wall model. To demonstrate the USCE system's ability to image tissue, a digital phantom was created from single-element ultrasonic transducer scans of porcine small bowel ex vivo obtained at a frequency of 45 MHz.

Low-FODMAP vs regular rye bread in irritable bowel syndrome: Randomized SmartPill® study

AIM

To compare the effects of regular vs low-FODMAP rye bread on irritable bowel syndrome (IBS) symptoms and to study gastrointestinal conditions with SmartPill^®.

METHODS

Our aim was to evaluate if rye bread low in FODMAPs would cause reduced hydrogen excretion, lower intraluminal pressure, higher colonic pH, different transit times, and fewer IBS symptoms than regular rye bread. The study was a randomized, double-blind, controlled cross-over meal study. Female IBS patients (n = 7) ate study breads at three consecutive meals during one day. The diet was similar for both study periods except for the FODMAP content of the bread consumed during the study day. Intraluminal pH, transit time, and pressure were measured by SmartPill, an indigestible motility capsule.

RESULTS

Hydrogen excretion (a marker of colonic fermentation) expressed as area under the curve (AUC)_{(0-630 min)} was [median (range)] 6300 (1785-10800) ppm∙min for low-FODMAP rye bread and 10 635 (4215-13080) ppm∙min for regular bread (P = 0.028). Mean scores of gastrointestinal symptoms showed no statistically significant differences but suggested less flatulence after low-FODMAP bread consumption (P = 0.063). Intraluminal pressure correlated significantly with total symptom score after regular rye bread (ρ = 0.786, P = 0.036) and nearly significantly after low-FODMAP bread consumption (ρ = 0.75, P = 0.052). We found no differences in pH, pressure, or transit times between the breads. Gastric residence of SmartPill was slower than expected. SmartPill left the stomach in less than 5 h only during one measurement (out of 14 measurements in total) and therefore did not follow on par with the rye bread bolus.

CONCLUSION

Low-FODMAP rye bread reduced colonic fermentation vs regular rye bread. No difference was found in median values of intraluminal conditions of the gastrointestinal tract.

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.

Relating gastric scintigraphy and symptoms to motility capsule transit and pressure findings in suspected gastroparesis

BACKGROUND

Wireless motility capsule (WMC) findings are incompletely defined in suspected gastroparesis. We aimed to characterize regional WMC transit and contractility in relation to scintigraphy, etiology, and symptoms in patients undergoing gastric emptying testing.

METHODS

A total of 209 patients with gastroparesis symptoms at NIDDK Gastroparesis Consortium centers underwent gastric scintigraphy and WMCs on separate days to measure regional transit and contractility. Validated questionnaires quantified symptoms.

KEY RESULTS

Solid scintigraphy and liquid scintigraphy were delayed in 68.8% and 34.8% of patients; WMC gastric emptying times (GET) were delayed in 40.3% and showed 52.8% agreement with scintigraphy; 15.5% and 33.5% had delayed small bowel (SBTT) and colon transit (CTT) times. Transit was delayed in ≥2 regions in 23.3%. Rapid transit was rarely observed. Diabetics had slower GET but more rapid SBTT versus idiopathics (P ≤ .02). GET delays related to greater scintigraphic retention, slower SBTT, and fewer gastric contractions (P ≤ .04). Overall gastroparesis symptoms and nausea/vomiting, early satiety/fullness, bloating/distention, and upper abdominal pain subscores showed no relation to WMC transit. Upper and lower abdominal pain scores (P ≤ .03) were greater with increased colon contractions. Constipation correlated with slower CTT and higher colon contractions (P = .03). Diarrhea scores were higher with delayed SBTT and CTT (P ≤ .04).

CONCLUSIONS & INFERENCES

Wireless motility capsules define gastric emptying delays similar but not identical to scintigraphy that are more severe in diabetics and relate to reduced gastric contractility. Extragastric transit delays occur in >40% with suspected gastroparesis. Gastroparesis symptoms show little association with WMC profiles, although lower symptoms relate to small bowel or colon abnormalities.

Is there an application for wireless capsule endoscopy in horses?

This pilot study assessed wireless capsule endoscopy in horses. Image transmission was achieved with good image quality. Time to exit the stomach was variable and identified as one limitation, together with gaps in image transmission, capsule tumbling, and inability to accurately locate the capsule. Findings demonstrate usefulness and current limitations.

In-to-out body path loss for wireless radio frequency capsule endoscopy in a human body

Physical-layer characterization is important for design of in-to-out body communication for wireless body area networks (WBANs). This paper numerically investigates the path loss of an in-to-out body radio frequency (RF) wireless link between an endoscopy capsule and a receiver outside the body using a 3D electromagnetic solver. A spiral antenna in the endoscopy capsule is tuned to operate in the Medical Implant Communication Service (MICS) band at 402 MHz, accounting for the properties of the human body. The influence of misalignment, rotation of the capsule, and human body model are investigated. Semi-empirical path loss models for various homogeneous tissues and 3D realistic human body models are provided for manufacturers to evaluate the performance of in-to-out-body WBAN systems.

Performance evaluation of power transmission coils for powering endoscopic wireless capsules

This paper presents an analysis of H-field generated by a simple solenoid, pair of solenoids, pair of double-layer solenoids, segmented-solenoid, and Helmholtz power transmission coils (PTCs) to power an endoscopic wireless capsule (WC). The H-fields were computed using finite element analysis based on partial differential equations. Three parameters were considered in the analysis: i) the maximum level of H-field (Hmax) to which the patient's body would be exposed, ii) the minimum level of H-field (Hmin) effective for power transmission, and iii) uniformity of H-field. We validated our analysis by comparing the computed data with data measured from a fabricated Helmholtz PTC. This analysis disclosed that at the same excitation power, all the PTCs are able to transfer same amount of minimum usable power since they generated almost equal value of Hmin. The level of electromagnetic exposure and power transfer stability across all the PTCs would vary significantly which is mainly due to the different level of Hmax and H-field uniformity. The segmented solenoid PTC would cause the lowest exposure and this PTC can transfer the maximum amount of power. The Helmholtz PTC would be able to transfer the most stable power with a moderate level of exposure.

A Therapeutic Wireless Capsule for Treatment of Gastrointestinal Haemorrhage by Balloon Tamponade Effect

OBJECTIVE

Wireless capsule endoscope (WCE) is a revolutionary approach to diagnose small bowel pathologies. Currently available WCEs are mostly passive devices with image capturing function only, while on-going efforts have been placed on robotizing WCEs or to enhance them with therapeutic functions. In this paper, the authors present a novel inflatable WCE for haemostasis in the gastrointestinal (GI) tracts by balloon tamponade effect.

METHODS

The proposed wireless capsule consists of a balloon that can be inflated using the endothermic reaction of acid and base. When the balloon reached a precalculated pressure level, it is able to stop at a bleeding site in the bowel, and achieve haemostasis by tamponade effect. The prototype is 14 mm in diameter, with three sections of 13, 35, and 12 mm in length, respectively. The three sections are linked together with flexible joints and enclosed in a silicone balloon. The prototypes were tested in ex vivo porcine intestine models.

RESULTS

In the ten ex vivo trials conducted, the inflatable wireless capsule achieved average balloon pressure of 46.0 mmHg and withstood average maximum longitudinal pulling force at 1.46 N. An in vivo study was carried out as a proof-of-concept for treating bleeding in a porcine model. The proposed inflatable WCE succeeded in the animal test by controlling haemostasis within 5 min. No rebleeding was observed in the next 20 min.

CONCLUSION

The results suggested that the inflatable capsule with a real-time bleeding detection algorithm can be implemented. Moreover, the proposed inflatable WCE prototype can achieve haemorrhage control in the lower GI.

SIGNIFICANCE

To our best knowledge, this is the first study that demonstrated the potential to treat GI haemorrhage by an inflatable WCE. The proposed capsule enables the development of a closed-loop system based on a body sensor network to provide early treatment of GI bleeding for p-medicine.

[Motility-recording capsule simplifies gastrointestinal examination. Safe diagnostics in motility disorders]

The wireless motility-recording capsule, "SmartPill", is an ingested one-time use electronic capsule that measures gastrointestinal luminal pressure, pH and temperature along the whole gastrointestinal tract. The pH profile and the pressure patterns define the time at which the capsule moves from the stomach to the duodenum and from the ileum to the caecum, whereas changes in temperature define the times of ingestion and expulsion. The recordings from the wireless motility capsule are sent from a radio transmitter in the capsule to a receiver carried around the waist. Wireless motility recordings have several advantages over imaging and manometry that have been used previously. Primarily the simplicity by which motility recordings are done, as well as the tolerability for the patient and limited need of assistance are valuable aspects. The wireless motility capsule provides standardized measures of transit with relevant normal values for the clinical work-up of patients with motility disturbances.

Development and Testing of a Magnetically Actuated Capsule Endoscopy for Obesity Treatment

Intra-gastric balloons (IGB) have become an efficient and less invasive method for obesity treatment. The use of traditional IGBs require complex insertion tools and flexible endoscopes to place and remove the balloon inside the patient’s stomach, which may cause discomfort and complications to the patient. This paper introduces a new ingestible weight-loss capsule with a magnetically remote-controlled inflatable and deflatable balloon. To inflate the balloon, biocompatible effervescent chemicals are used. As the source of the actuation is provided via external magnetic fields, the magnetic capsule size can be significantly reduced compared to current weight-loss capsules in the literature. In addition, there are no limitations on the power supply. To lose weight, the obese subject needs only to swallow the magnetic capsule with a glass of water. Once the magnetic capsule has reached the patient’s stomach, the balloon will be wirelessly inflated to occupy gastric space and give the feeling of satiety. The balloon can be wirelessly deflated at any time to allow the magnetic capsule to travel down the intestine and exit the body via normal peristalsis. The optimal ratio between the acid and base to provide the desired gas volume is experimentally evaluated and presented. A prototype capsule (9.6mm x 27mm) is developed and experimentally validated in ex-vivo experiments. The unique ease of delivery and expulsion of the proposed magnetic capsule is slated to make this development a good treatment option for people seeking to lose excess weight.

[Improvement of Digital Capsule Endoscopy System and Image Interpolation]

Traditional capsule image collects and transmits analog image, with weak anti-interference ability, low frame rate, low resolution. This paper presents a new digital image capsule, which collects and transmits digital image, with frame rate up to 30 frames/sec and pixels resolution of 400 x 400. The image is compressed in the capsule, and is transmitted to the outside of the capsule for decompression and interpolation. A new type of interpolation algorithm is proposed, which is based on the relationship between the image planes, to obtain higher quality colour images. capsule endoscopy, digital image, SCCB protocol, image interpolation

Enteroscopy

Noninvasive imaging with CT and magnetic resonance enterography or direct visualization with wireless capsule endoscopy can provide valuable diagnostic information and direct therapy. Enteroscopy technology and techniques have evolved significantly and allow diagnosis and therapy deep within the small bowel, previously attainable only with intraoperative enteroscopy. Push enteroscopy, readily available in most endoscopy units, plays an important role in the evaluation and management of lesions located up to the proximal jejunum. Currently available device-assisted enteroscopy systems, DBE, SBE, and spiral enteroscopy each have their technical nuances, clinical advantages, and limitations. Newer, on-demand enteroscopy systems appear promising, but further studies are needed. Despite slight differences in parameters such as procedural times, depths of insertion, and rates of complete enteroscopy, the overall clinical outcomes with all overtube-assisted systems appear to be similar. Endoscopists should therefore master the enteroscopy technology based on institutional availability and their level of technical expertise.

Overview of technical solutions and assessment of clinical usefulness of capsule endoscopy

The paper presents an overview of endoscopic capsules with particular emphasis on technical aspects. It indicates common problems in capsule endoscopy such as: (1) limited wireless communication (2) the use of capsule endoscopy in the case of partial patency of the gastrointestinal tract, (3) limited imaging area, (4) external capsule control limitations. It also presents the prospects of capsule endoscopy, the most recent technical solutions for biopsy and the mobility of the capsule in the gastrointestinal tract. The paper shows the possibilities of increasing clinical usefulness of capsule endoscopy resulting from technological limitations. Attention has also been paid to the current role of capsule endoscopy in screening tests and the limitations of its effectiveness. The paper includes the author's recommendations concerning the direction of further research and the possibility of enhancing the scope of capsule endoscopy.

Bayesian-based localization of wireless capsule endoscope using received signal strength

In wireless body area sensor networking (WBASN) applications such as gastrointestinal (GI) tract monitoring using wireless video capsule endoscopy (WCE), the performance of out-of-body wireless link propagating through different body media (i.e. blood, fat, muscle and bone) is still under investigation. Most of the localization algorithms are vulnerable to the variations of path-loss coefficient resulting in unreliable location estimation. In this paper, we propose a novel robust probabilistic Bayesian-based approach using received-signal-strength (RSS) measurements that accounts for Rayleigh fading, variable path-loss exponent and uncertainty in location information received from the neighboring nodes and anchors. The results of this study showed that the localization root mean square error of our Bayesian-based method was 1.6 mm which was very close to the optimum Cramer-Rao lower bound (CRLB) and significantly smaller than that of other existing localization approaches (i.e. classical MDS (64.2mm), dwMDS (32.2mm), MLE (36.3mm) and POCS (2.3mm)).

Capsule enteroscopy is useful for the therapeutic management of Crohn’s disease

AIM: To analyze therapeutic changes in Crohn’s disease (CD) patients following video capsule endoscopy (VCE) and to assess the usefulness of Lewis score and the Patency Capsule.

METHODS: Patency Capsule was performed in every patient that had indication for VCE, and those with negative patency did not undergo VCE. Patients with established CD that underwent VCE between January 2011 and February 2014 were selected for this study; those with suspected CD were excluded, independent of VCE results, since our purpose was to address differences in therapeutic regimen in CD patients before and after VCE. Patients with inconclusive VCE were also excluded. Patients had to be free of non-steroidal anti-inflammatories for at least 1 mo. Those patients who met these criteria were allocated into one of three groups: Staging group (asymptomatic CD patients that underwent VCE for staging of CD), Flare group (patients with active CD), or Post-op group (CD patients evaluated for post-operative recurrence). Lewis score was calculated for every VCE procedure. Statistical analysis was performed to address the impact of VCE findings on the therapeutic management of CD patients and to evaluate the utility of the Lewis score.

RESULTS: From a total of 542 VCEs, 135 were performed in patients with CD. Patency capsule excluded nearly 25% of the patients who were supposed to undergo VCE. No videocapsule retention during VCE was reported. From these 135 patients, 29 were excluded because CD diagnosis was not established at the time of VCE. Therefore, a total of 106 patients were included in the final analysis. From these, the majority were in the Staging group (n = 73, 69%), and the remaining were in the Flare (n = 23, 22%) or Post-op (n = 10, 9%) group. Median time between diagnosis and VCE was 5.5 years. Overall, VCE determined changes in the treatment of 40% of patients: only 21% remained free of immunosuppressors after VCE compared to 44% before VCE (P < 0.001). The differences in therapy before and after VCE achieved statistical significance in the Staging and Flare groups. In addition, patients were significantly different when stratified regarding time since diagnosis to the date of VCE. A higher Lewis score was associated with therapeutic modifications (P < 0.0001); where a score higher than 1354 was related to 90% probability of changing therapy [area under the receiver operative characteristic (AUROC) 0.80 (95%CI: 0.69-0.88)].

CONCLUSION: VCE significantly changed the therapeutic management of CD patients, even in those with long-term disease. Systematic use of Patency capsule allowed for no videocapsule retention.

A UWB wireless capsule endoscopy device

Wireless capsule endoscopy (WCE) presents many advantages over traditional wired endoscopic methods. The performance of WCE devices can be improved using high-frequency communication systems such as Impulse Radio-Ultra-Wideband (IR-UWB) to enable a high data rate transmission with low-power consumption. This paper presents the hardware implementation and experimental evaluation of a WCE device that uses IR-UWB signals in the frequency range of 3.5 GHz to 4.5 GHz to transmit image data from inside the body to a receiver placed outside the body. Key components of the IR-UWB transmitter, such as the narrow pulse generator and up-conversion based RF section are described in detail. This design employs a narrowband receiver in the WCE device to receive a control signal externally in order to control and improve the data transmission from the device in the body. The design and performance of a wideband implantable antenna that operates in the aforementioned frequency range is also described. The operation of the WCE device is demonstrated through a proof-of-concept experiment using meat.

What Kind of Capsule Endoscope Is Suitable for a Controllable Self-Propelling Capsule Endoscope? Experimental Study Using a Porcine Stomach Model for Clinical Application (with Videos)

Background

We have been developing the Self-Propelling Capsule Endoscope (SPCE) that allows for controllability from outside of the body and real-time observation. What kind of capsule endoscope (CE) is suitable for a controllable SPCE is unclear and a very critical point for clinical application. We compared observing ability of three kinds of SPCEs with different viewing angles and frame rates.

Methods

Eleven buttons were sewed in an excised porcine stomach. Four examiners controlled the SPCE using PillCamSB2, -ESO2, and -COLON2 (Given Imaging Ltd., Israel), for 10 minutes each with the aim of detecting as many buttons and examining them as closely as possible. The ability to find lesions was assessed based on the number of detected buttons. The SPCE-performance score (SPS) was used to evaluate the ability to examine the lesions in detail.

Results

The SPCE-ESO2, -COLON2, and -SB2 detected 11 [interquartile range (IQR): 0], 10.5 (IQR, 0.5), and 8 (IQR, 1.0) buttons, respectively. The SPCE-ESO2 and -COLON2 had a significantly better ability to detect lesions than the -SB2 (p < 0.05). The SPCE-ESO2, -COLON2, and -SB2 had significantly different SPS values of 22 (IQR, 0), 16.5 (IQR, 1.5), and 14 (IQR, 1.0), respectively (p < 0.05 for all comparisons; SPCE-SB2 vs. -ESO2, -SB2 vs. -COLON2, and -ESO2 vs. -COLON2).

Conclusions

PillCamESO2 is most suitable in different three CEs for SPCE for examining lesions in detail of the stomach.

OdoCapsule: next-generation wireless capsule endoscopy with accurate lesion localization and video stabilization capabilities

In this paper, we propose a platform to achieve accurate localization of small-bowel lesions and endoscopic video stabilization in wireless capsule endoscopy. Current research modules rely on the use of external magnetic fields and triangulation methods to calculate the position vector of the capsule, leading to considerable error margins. Our platform, entitled OdoCapsule (a synthesis of the words Odometer and Capsule), provides real-time distance information from the point of duodenal entry to the point of exit from the small bowel. To achieve this, OdoCapsule is equipped with three miniature legs. Each leg carries a soft rubber wheel, which is made with human-compliant material. These legs are extendable and retractable thanks to a micromotor and three custom-made torsion springs. The wheels are specifically designed to function as microodometers: each rotation they perform is registered. Hence, the covered distance is measured accurately in real time. Furthermore, with its legs fully extended, OdoCapsule can stabilize itself inside the small-bowel lumen thus offering smoother video capture and better image processing. Recent ex vivo testing of this concept, using porcine small bowel and a commercially available (custom-modified) capsule endoscope, has proved its viability.

Intraoperative bowel cleansing tool in active locomotion capsule endoscopy

Capsule endoscopy (CE) can be considered an example of "disruptive technology" since it represents a bright alternative to traditional diagnostic methodologies. If compared with traditional endoscopy, bowel cleansing procedure in CE becomes of greater importance, due to the impossibility to intraoperatively operate on unclean gastrointestinal tract areas. Considering the promising results and benefits obtained in the field of CE for gastrointestinal diagnosis and intervention, the authors approached the bowel cleansing issue with the final aim to propose an innovative and easy-to-use intraoperative cleansing system to be applied to an active locomotion softly-tethered capsule device, already developed by the authors. The system, that has to be intended as an additional tool for intraoperatively cleansing procedure of the colonic tract, is composed by a flexible tube with a metallic deflector attached to the distal end; it can be headed to the target area through the capsule operating channel. Performances of the colonoscopic capsule and intraoperative cleansing capabilities were successfully confirmed both in an in-vitro and ex-vivo experimental session. The innovative intraoperative cleansing system demonstrated promising results in terms of water injection, colonic wall cleansing procedure and subsequent water suction, thus guaranteeing to reduce the risk of inadequate visualization of the mucosa in endoscopic procedures.

PillCam COLON 2© in Crohn’s disease: A new concept of pan-enteric mucosal healing assessment

AIM: To evaluate mucosal healing in patients with small bowel plus colonic Crohn’s disease (CD) with a single non-invasive examination, by using PillCam COLON 2^© (PCC2).

METHODS: Patients with non-stricturing nonpenetrating small bowel plus colonic CD in sustained corticosteroid-free remission were included. At diagnosis, patients had undergone ileocolonoscopy to identify active CD lesions, such as ulcers and erosions, and small bowel capsule endoscopy to assess the Lewis Score (LS). After ≥ 1 year of follow-up, patients underwent entire gastrointestinal tract evaluation with PCC2. The primary endpoint was assessment of CD mucosal healing, defined as no active colonic CD lesions and LS < 135.

RESULTS: Twelve patients were included (7 male; mean age: 32 years), and mean follow-up was 38 mo. The majority of patients (83.3%) received immunosuppressive therapy. Three patients (25%) achieved mucosal healing in both the small bowel and the colon, while disease activity was limited to either the small bowel or the colon in 5 patients (42%). It was possible to observe the entire gastrointestinal tract in 10 of the 12 patients (83%) who underwent PCC2.

CONCLUSION: Only three patients in sustained corticosteroid-free clinical remission achieved mucosal healing in both the small bowel and the colon, highlighting the limitations of clinical assessment when stratifying disease activity, and the need for pan-enteric endoscopy to guide therapeutic modification.

Comparison of the diagnostic yield and outcomes between standard 8 h capsule endoscopy and the new 12 h capsule endoscopy for investigating small bowel pathology

AIM: To evaluate the completion rate and diagnostic yield of the PillCam SB2-ex in comparison to the PillCam SB2.

METHODS: Two hundred cases using the 8-h PillCam SB2 were retrospectively compared to 200 cases using the 12 h PillCam SB2-ex at a tertiary academic center. Endoscopically placed capsules were excluded from the study. Demographic information, indications for capsule endoscopy, capsule type, study length, completion of exam, clinically significant findings, timestamp of most distant finding, and significant findings beyond 8 h were recorded.

RESULTS: The 8 and 12 h capsule groups were well matched respectively for both age (70.90 ± 14.19 vs 71.93 ± 13.80, P = 0.46) and gender (45.5% vs 48% male, P = 0.69). The most common indications for the procedure in both groups were anemia and obscure gastrointestinal bleeding. PillCam SB2-ex had a significantly higher completion rate than PillCam SB2 (88% vs 79.5%, P = 0.03). Overall, the diagnostic yield was greater for the 8 h capsule (48.5% for SB2 vs 35% for SB2-ex, P = 0.01). In 4/70 (5.7%) of abnormal SB2-ex exams the clinically significant finding was noted in the small bowel beyond the 8 h mark.

CONCLUSION: In our study, we found the PillCam SB2-ex to have a significantly increased completion rate, though without any improvement in diagnostic yield compared to the PillCam SB2.

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.

Effect of longer battery life on small bowel capsule endoscopy

AIM: To determine if longer battery life improves capsule endoscopy (CE) completion rates.

METHODS: A retrospective study was performed at a tertiary, university-affiliated hospital in Vancouver, Canada. Patients who underwent CE with either PillCam™ SB2 or SB2U between 01/2010 and 12/2013 were considered for inclusion. SB2 and SB2U share identical physical dimensions but differ in their battery lives (8 h vs 12 h). Exclusion criteria included history of gastric or small bowel surgery, endoscopic placement of CE, interrupted view of major landmarks due to technical difficulty or significant amount of debris, and repeat CE using same system. Basic demographics, comorbidities, medications, baseline bowel habits, and previous surgeries were reviewed. Timing of major landmarks in CE were recorded, and used to calculate gastric transit time, small bowel transit time, and total recording time. A complete CE study was defined as visualization of cecum. Transit times and completion rates were compared.

RESULTS: Four hundred and eight patients, including 208 (51.0%) males, were included for analysis. The mean age was 55.5 ± 19.3 years. The most common indication for CE was gastrointestinal bleeding (n = 254, 62.3%), followed by inflammatory bowel disease (n = 86, 21.1%). There was no difference in gastric transit times (group difference 0.90, 95%CI: 0.72-1.13, P = 0.352) and small bowel transit times (group difference 1.07, 95%CI: 0.95-1.19, P = 0.261) between SB2U and SB2, but total recording time was about 14% longer in the SB2U group (95%CI: 10%-18%, P < 0.001) and there was a corresponding trend toward higher completion rate (88.2% vs 93.2%, OR = 1.78, 95%CI 0.88-3.63, P = 0.111). There was no statistically significant difference in the rates of positive findings (OR = 0.98, 95%CI: 0.64-1.51, P = 0.918).

CONCLUSION: Extending the operating time of CE may be a simple method to improve completion rate although it does not affect the rate of positive findings.

[Second-generation colon capsule in small bowel and colon disorders in pediatrics]

BACKGROUND

Aim of the study was to assess the diagnostic yield of second-generation colon capsule in pediatric gastrointestinal diseases.

PATIENTS AND METHODS

Five patients with different symptoms of gastrointestinal diseases were included in the study. Among them were: suspicion on diffuse polyposis, intestinal bleeding, lymphangiectasia and inflammatory bowel disease. Image interpretation was made by experienced capsule users, previously trained on small bowel capsule and first generation colon capsule. Lesions or abnormal changes of the mucosa identified on capsule endoscopy served as indications for colonoscopy or esophagogastroduodenoscopy with biopsy or polypectomy if needed.

RESULTS

Standard white light endoscopy was made in all children without any adverse events. Second-generation colon capsule allows diagnosing Crohn's disease in small intestine and colon, limphangiectasia of the ileum, single rectosigmoid polyp and diffuse polyposis of the colon.

CONCLUSION

Second-generation colon capsule can be used as non-invasive screening method in children without serious complications, thus allowing to differentiate indications for traditional white light endoscopy, which is usually made under general anesthesia in pediatrics.

[Latest development of intestinal capsule endoscopy robot]

With the development of capsule endoscopy, developing active capsule endoscopy robot becomes a growing trend. Although stomach diagnosis with robot has been put into clinical test, the realization of the complete intestinal capsule endoscopy is still a difficulty. This paper reports the status quo of the research process for intestinal capsule endoscopy robot, and analyzes their advantages, defects and prospects for development, which provides reference for the research of intestinal capsule endoscopy robot.

Matching layer for path loss reduction in ultra wideband implant communications

Real-time monitoring of various physiological signals is of utmost importance for the treatment of chronic conditions. Radio technology can enable real-time sensing and collection of physiological data to facilitate timely medication and early pre-hospital management of patients. This can be realized with the aid of implantable biomedical sensors with the capability to transmit wirelessly the collected information to an external unit for display and analysis. Currently, commercial wireless medical implantable sensors operate in frequencies below 1 GHz with narrowband signals. Recently, it has been demonstrated that ultra wideband (UWB) signals could be also used for the radio interface of these devices. However, establishing an implant communication link in the allocated UWB spectrum of 3.1-10.6 GHz is challenging. The attenuation of UWB signals propagating through biological tissues at these frequencies is high. Part of these path losses are caused by the impedance mismatch between the two propagation environments (i.e., air and biological tissues) that constitute an implant communication link. This mismatch results in inefficient power transmission of the radio waves. In this paper we propose the use of a layer of dielectric material that can be applied on the patient's skin. The permittivity value of this matching layer has to be chosen such that wave coupling is maximized. Through numerical simulations we determined the appropriate permittivity value of a matching layer for UWB implant communication links in the human thorax for 1-6 GHz. Path loss reduction of up to 10 dB can be obtained in this frequency band. These results can help improve the use of UWB signals for other in-body biomedical devices like the wireless capsule endoscope (WCE).

Subject-friendly entire gastrointestinal screening with a single capsule endoscope by magnetic navigation and the Internet

Ever since capsule endoscopy (CE) was introduced into clinical practice, we gastroenterologists have been dreaming of using this less invasive modality to explore the entire gastrointestinal (GI) tract. To realize this dream, we have developed a magnetic navigation system which includes real-time internet streaming of endoscopic video and some useful gadgets (position detection by means of magnetic impedance (MI) sensors and a modified capsule that is "weightless" in water). The design of the weightless capsule made it possible with 0.5T (Tesla) extracorporeal magnets to control the capsule beyond 20cm. A pair of MI sensors on the body surface could detect subtle magnetic flux generated by an intra-capsular magnet in the GI tract by utilizing the space diversity effect which eliminated the interference of terrestrial magnetism. Subjects underwent CE, during which they were free from confinement in the hospital, except for 1 hour when the capsule was manipulated in the stomach and colon. This study had a completion rate of 97.5%. The high completion rate indicates that our system (single capsule endoscopy-SCE) with further improvements could become a viable modality for screening of the entire GI tract.

A video-based speed estimation technique for localizing the wireless capsule endoscope inside gastrointestinal tract

Wireless Capsule Endoscopy (WCE) is progressively emerging as one of the most popular non-invasive imaging tools for gastrointestinal (GI) tract inspection. As a critical component of capsule endoscopic examination, physicians need to know the precise position of the endoscopic capsule in order to identify the position of intestinal disease. For the WCE, the position of the capsule is defined as the linear distance it is away from certain fixed anatomical landmarks. In order to measure the distance the capsule has traveled, a precise knowledge of how fast the capsule moves is urgently needed. In this paper, we present a novel computer vision based speed estimation technique that is able to extract the speed of the endoscopic capsule by analyzing the displacements between consecutive frames. The proposed approach is validated using a virtual testbed as well as the real endoscopic images. Results show that the proposed method is able to precisely estimate the speed of the endoscopic capsule with 93% accuracy on average, which enhances the localization accuracy of the WCE to less than 2.49 cm.

Wireless Micro-Ball endoscopic image enhancement using histogram information

Wireless endoscopy systems is a new innovative method widely used for gastrointestinal tract examination in recent decade. Wireless Micro-Ball endoscopy system with multiple image sensors is the newest proposed method which can make a full view image of the gastrointestinal tract. But still the quality of images from this new wireless endoscopy system is not satisfactory. It's hard for doctors and specialist to easily examine and interpret the captured images. The image features also are not distinct enough to be used for further processing. So as to enhance these low-contrast endoscopic images a new image enhancement method based on the endoscopic images features and color distribution is proposed in this work. The enhancement method is performed on three main steps namely color space transformation, edge preserving mask formation, and histogram information correction. The luminance component of CIE Lab, YCbCr, and HSV color space is enhanced in this method and then two other components added finally to form an enhanced color image. The experimental result clearly show the robustness of the method.

Technical feasibility of patient-friendly screening and treatment of digestive disease by remote control robotic capsule endoscopes via the internet

A few types of steerable capsule endoscopes have been proposed but disappointingly their systems were not applicable to common endoscopic treatment or pathological diagnosis. This study validates the possibility of treatment and biopsy by using an internet-linked (wireless control via the internet) robotic capsule endoscope (iRoboCap). iRoboCap consisted of three parts: an imaging unit, a movement control unit and a therapeutic tool unit. Two types of iRoboCaps were designed, one was a submarine type (iRoboCap-S) and the other was an amphibious type (iRoboCap-A). They were remotely and wirelessly steered by a portable tablet device using Bluetooth and via the internet. The success rates of biopsy or clipping were evaluated in a phantom. Although the two prototypes have various problems that need improving, we hope that our robotic and wireless innovations have opened the door to new endoscopic procedures and will pioneer various new applications in medicine.

Effectiveness of using low-dose computed tomography to assess patency in gastrointestinal tracts with a patency capsule

BACKGROUND/AIMS

A patency capsule (PC) is used to safely perform capsule endoscopy. When the PC is not excreted within the defined time frame, radiography often cannot localize the PC. Computed tomography (CT) localizes a PC more definitively than radiography. We evaluated the localization of PCs using low-dose (LD)-CT.

METHODOLOGY

Forty-nine patients received a PC and 33 did not excrete the PC within the defined time frame and underwent radiography and LDCT with a 90% exposure reduction.

RESULTS

LDCT localized the PC in 31 patients (93.9%), whereas radiography localized it in 7 (21.2%), indicating a significantly higher detection rate with LDCT (P<0.0001). PC retention in the small intestine was confirmed by LDCT in 4 patients. Retention was not observed during capsule endoscopy in the patients with confirmed patency of the gastrointestinal tract. In 21 patients who underwent LDCT with the conventional photographing area, the effective radiographic exposure dose associated with LDCT was 1.43±1.08 mSv. Conversely, in the 12 patients who underwent LDCT with a reduced photographing area, the effective dose was reduced to 0.62±0.27 mSv (P<0.05).

CONCLUSION

LDCT with a reduced exposure dose can definitively localize a PC. Therefore, this method may allow capsule endoscopy to be performed for more diseases.

[COLON CAPSULE ENDOSCOPY IN CLINICAL EXPERIENCE]

AIM

Is to evaluate technical aspects and feasibility of colon capsule endoscopy (CCE) in the daily clinical practice.

MATERIALS AND METHODS

From I.2014 to VIII.2014 we performed 36 (97.3%) CCE from 37 patients (m-19, f-17, mean age 43.9 ± 14.2 years, range 22-72).

RESULTS

Total CCE was performed in 33 (89.2%) patients. In all patients we were able to register anatomy and to evaluate the lumen and the wall of large bowel; to explore and identify mucosal abnormality as well as epithelial lesions.

CONCLUSION

The article demonstrates our own experience of colon capsule endoscopy (n = 36); the principal possibilities to evaluate colon anatomy and to detect wide range of abnormality.

Wireless communication link for capsule endoscope at 600 MHz

Simulation of a wireless communication link for a capsule endoscopy is presented for monitoring of small intestine in humans. The realized communication link includes the transmitting capsule antenna, the outside body receiving antenna and the model of the human body. The capsule antenna is designed for operating at the frequency band of 600 MHz with an impedance bandwidth of 10 MHz and omnidirectional radiation pattern. The quality of the communication link is improved by using directive antenna outside body inside matching layer for electromagnetic wave tuning to the body. The outside body antenna has circular polarization that guaranteeing the communication link for different orientations of the capsule inside intestine. It is shown that the path loss for the capsule in 60 mm from the abdomen surface varies between 37-47 dB in relation to the antenna orientation. This link can establish high data rate wireless communications for capsule endoscopy.

A platform for gastric cancer screening in low- and middle-income countries

Gastric cancer is the second leading cause of cancer death worldwide and screening programs have had a significant impact on reducing mortality. The majority of cases occur in low- and middle-income countries (LMIC), where endoscopy resources are traditionally limited. In this paper, we introduce a platform designed to enable inexpensive gastric screening to take place in remote areas of LMIC. The system consists of a swallowable endoscopic capsule connected to an external water distribution system by a multichannel soft tether. Pressurized water is ejected from the capsule to orient the view of the endoscopic camera. After completion of a cancer screening procedure, the outer shell of the capsule and the soft tether can be disposed, while the endoscopic camera is reclaimed without needing further reprocessing. The capsule, measuring 12 mm in diameter and 28 mm in length, is able to visualize the inside of the gastric cavity by combining waterjet actuation and the adjustment of the tether length. Experimental assessment was accomplished through a set of bench trials, ex vivo analysis, and in vivo feasibility validation. During the ex vivo trials, the platform was able to visualize the main landmarks that are typically observed during a gastric cancer screening procedure in less than 8 min. Given the compact footprint, the minimal cost of the disposable parts, and the possibility of running on relatively available and inexpensive resources, the proposed platform can potentially widen gastric cancer screening programs in LMIC.

Video capsule endoscopy: Perspectives of a revolutionary technique

Video capsule endoscopy (VCE) was launched in 2000 and has revolutionized direct endoscopic imaging of the gut. VCE is now a first-line procedure for exploring the small bowel in cases of obscure digestive bleeding and is also indicated in some patients with Crohn’s disease, celiac disease, and polyposis syndrome. A video capsule has also been designed for visualizing the esophagus in order to detect Barrett’s esophagus or esophageal varices. Different capsules are now available and differ with regard to dimensions, image acquisition rate, battery life, field of view, and possible optical enhancements. More recently, the use of VCE has been extended to exploring the colon. Within the last 5 years, tremendous developments have been made toward increasing the capabilities of the colon capsule. Although colon capsule cannot be proposed as a first-line colorectal cancer screening procedure, colon capsule may be used in patients with incomplete colonoscopy or in patients who are unwilling to undergo colonoscopy. In the near future, new technological developments will improve the diagnostic yield of VCE and broaden its therapeutic capabilities.