Review: capsule colonoscopy-a concise clinical overview of current status

Metabolites: a converging node of host and microbe to explain meta-organism

Meta-organisms encompassing the host and resident microbiota play a significant role in combatting diseases and responding to stress. Hence, there is growing traction to build a knowledge base about this ecosystem, particularly to characterize the bidirectional relationship between the host and microbiota. In this context, metabolomics has emerged as the major converging node of this entire ecosystem. Systematic comprehension of this resourceful omics component can elucidate the organism-specific response trajectory and the communication grid across the ecosystem embodying meta-organisms. Translating this knowledge into designing nutraceuticals and next-generation therapy are ongoing. Its major hindrance is a significant knowledge gap about the underlying mechanisms maintaining a delicate balance within this ecosystem. To bridge this knowledge gap, a holistic picture of the available information has been presented with a primary focus on the microbiota-metabolite relationship dynamics. The central theme of this article is the gut-brain axis and the participating microbial metabolites that impact cerebral functions.

Anatomical landmarks localization for capsule endoscopy studies

Wireless Capsule Endoscopy is a medical procedure that uses a small, wireless camera to capture images of the inside of the digestive tract. The identification of the entrance and exit of the small bowel and of the large intestine is one of the first tasks that need to be accomplished to read a video. This paper addresses the design of a clinical decision support tool to detect these anatomical landmarks. We have developed a system based on deep learning that combines images, timestamps, and motion data to achieve state-of-the-art results. Our method does not only classify the images as being inside or outside the studied organs, but it is also able to identify the entrance and exit frames. The experiments performed with three different datasets (one public and two private) show that our system is able to approximate the landmarks while achieving high accuracy on the classification problem (inside/outside of the organ). When comparing the entrance and exit of the studied organs, the distance between predicted and real landmarks is reduced from 1.5 to 10 times with respect to previous state-of-the-art methods.

Emerging wearable technology applications in gastroenterology: A review of the literature

The field of gastroenterology has recently seen a surge in wearable technology to monitor physical activity, sleep quality, pain, and even gut activity. The past decade has seen the emergence of wearable devices including Fitbit, Apple Watch, AbStats, and ingestible sensors. In this review, we discuss current and future devices designed to measure sweat biomarkers, steps taken, sleep efficiency, gastric electrical activity, stomach pH, and intestinal contents. We also summarize several clinical studies to better understand wearable devices so that we may assess their potential benefit in improving healthcare while also weighing the challenges that must be addressed.

Measuring Microbiome Effectiveness: A Role for Ingestible Sensors

Across the world there is an increasingly heavy burden of noncommunicable diseases related to obesity, mental health, and atopic disease. In a previous publication, we followed the developing idea that that these conditions arise as our microbiome loses diversity, but there seems to be no generally applicable way to assess the significance of this loss. Our work revisited the findings of the African studies by Denis Burkitt who reported that the frequency of what he called Western diseases were inversely proportional to the average faecal volumes of affected populations. Although he ascribed this to fibre in the diet, it now seems more likely that the drop in faecal volume with the onset of disease is due to the loss of a fully functioning microbiome. We suggested that the microbiome could be considered to be a single mutualistic microbial community interacting with our body by two complementary sets of semiochemicals, i.e., allomones to feed the microbiota by facilitating the efficient transfer of nutrition through the gut and kairomones to calibrate our immune system by an as yet unknown mechanism. The bioactive compounds, dopamine and serotonin, are known to be present in the gut lumen under the influence of intestinal microbiota and we suggest that these are part of this allomone-like system. In light of this possibility, it is of critical importance to develop a method of quantifying the microbiome effectiveness. Ingestible sensors consist of a miniaturized detector and transmitter packed into a capsule that is swallowed and tracked through the intestine. The aim of this article is to explore the possible development of such ingestible detectors for these or other compounds that can act as a surrogate marker for microbiome effectiveness. We consider that the ability to provide real-time quantitative information on the interaction of the microbiome with different nutrients promises to be a valuable new tool to unravel the mystery of these noncommunicable illnesses, i.e., microbiome-function deficiency diseases.

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.

Video capsule colonoscopy in routine clinical practice

BACKGROUND

Colon capsule endoscopy (CCE) offers direct mucosal visualisation without sedation or gas insufflation required in conventional colonoscopy (CC). However, evidence for the role of CCE as an adjunct or alternative to CC remains equivocal. In this observational cohort study, we report our experience of using CCE to investigate patients with suspected colon pathology at a tertiary referral centre.

METHODS

From 2007-2015, consecutive patients requiring colonoscopy were recruited from a tertiary care centre in Malmo, Sweden. Data collected: patient demographics, indication for CCE, findings, bowel cleansing, colon transit time (CTT) and completeness of colon examination.

RESULTS

Seventy-seven patients (57 F/20 F, median age 56 years) were included. The reason for CCE was previously incomplete or refused CC in 39 and 26 cases, and follow up of previous findings in 12 cases, respectively. The main clinical indications were gastrointestinal (GI) bleeding (n=28; 36%) and suspected inflammatory bowel disease (IBD) or follow-up of known IBD (n=23; 30%). CCE was complete in 58/77 (75%) patients. In 3 patients the colon was not reached; in the other 16, the capsule reached the rectum (n=4), sigmoid (n=6), descending colon (n=5) and transverse colon (n=1). Findings were: normal CCE (n=15; 19%) colonic diverticula (n=29; 38%), polyps (n=17; 22%), active IBD (n=12; 16%), haemorrhoids (n=8; 10%), colonic angioectasia (n=4; 5%) and cancer (n=1; 1%). Small-bowel findings were recorded in 8 (10%) patients. All patients tolerated bowel preparation and CCE well. Two patients with an ulcerated small-bowel stricture and cancer respectively experienced temporary capsule retention with spontaneous resolution.

CONCLUSIONS

CCE is a well-tolerated alternative to CC, but requires technological improvement and optimisation of clinical practice to meet current reference standards. Although further technical development is required, CCE may complement or even replace CC for certain clinical indications.

Is capsule colonoscopy the solution for incomplete conventional colonoscopy?

The era of colon capsule endoscopy (CCE) started in 2007. Few years later second-generation CCE (CCE-2) (Medtronic, Minneapolis, USA) was launched, featuring an improved optical system allowing for nearly 360° coverage via two 172° angle cameras, and adaptive frame rate function (ranging from 4 to 35 images per second depending on capsule motion). At present the main clinical indications for CCE are: a) completion of incomplete colonoscopy; b) polyp detection; and c) investigation of inflammatory bowel disease (IBD).