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Endoscopic images depicting Crohn’s disease (CD) and ulcerative colitis (UC) lesions with different techniques and resolutions: image (a) shows a moderate to severe Crohn’s colitis, while (b) shows a mild UC (endoscopic Mayo 1), both in standard definition. Images (c) and (d) depict again a distal UC involvement in high-definition white light (HD-WLE) as well as in digital chromoendoscopy using i-Scan (Mayo 1–2). In comparison, pictures (e) and (f) show a severe CD of the ileum and colon (high-definition WLE and i-Scan). Images (g) and (h) show high-definition WLE and narrow-band imaging (NBI) (h) of a gastric CD, highlighting erosions and aphthoid lesions.
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Endoscopy remains the most important diagnostic and monitoring modality in the management of inflammatory bowel disease. Advances in imaging have progressively added new tools into the armamentarium of endoscopists with the goal of more accurate, sensitive, and accessible visual diagnoses for the benefit of patients with gastrointestinal diseases....
Citations
... Therefore, proper diagnosis is required [45]. The infection usually begins in the rectum and spreads proximally in an unbroken pattern, affecting part or all of the colon [46]. The severity of the disease might be characterized as proctitis, left-sided colitis, or pancolitis, depending on the intestinal segments affected. ...
... Pancolitis patients may have several forms of inflammation in the terminal ileum's distal few cm. This symptom, sometimes known as backwash ileitis, and rectal sparing are significantly associated with primary sclerosing cholangitis [6,46]. ...
Ulcerative colitis (UC) is a multifactorial disorder of the large intestine, especially the colon, and has become a challenge globally. Allopathic medicines are primarily available for the treatment and prevention of UC. However, their uses are limited due to several side effects. Hence, an alternative therapy is of utmost importance in this regard. Herbal medicines are considered safe and effective for managing human health problems. Chlorogenic acid (CGA), the herbal-derived bioactive, has been reported for pharmacological effects like antiinflammatory, immunomodulatory, antimicrobial, hepatoprotective, antioxidant, anticancer, etc. This review aims to understand the antiinflammatory and chemopreventive potential of CGA against UC. Apart from its excellent therapeutic potential, it has been associated with low absorption and poor oral bioavailability. In this context, colon-specific novel drug delivery systems (NDDS)are pioneering to overcome these problems. The pertinent literature was compiled from a thorough search on various databases such as ScienceDirect, PubMed, Google Scholar, etc., utilizing numerous keywords, including ulcerative colitis, herbal drugs, CGA, pharmacological activities, mechanism of actions, nanoformulations, clinical updates, and many others. Relevant publications accessed till now were chosen, whereas non-relevant papers, unpublished data, and non-original articles were excluded. The present review comprises recent studies on pharmacological activities and novel drug delivery systems of CGA for managing UC. In addition, the clinical trials of CGA against UC have been discussed.
... Although CLE can easily identify dysplastic regions of the mucosal layer and guide targeted endoscopic interventions, it has limited applicability. It cannot cover the whole gastrointestinal tract because it can only see a limited field of vision [145]. Therefore, before using CLE, it is necessary to use other macroscopic techniques such as CE to find suspicious areas and targeted biopsies. ...
Patients with ulcerative colitis (UC) are at a two- to three-fold increased risk of developing colorectal cancer (CRC) than the general population based on population-based data. UC-CRC has generated a series of clinical problems, which are reflected in its worse prognosis and higher mortality than sporadic CRC. Chronic inflammation is a significant contributor to the development of UC-CRC, so comprehending the relationship between the proinflammatory factors and epithelial cells together with downstream signaling pathways is the core to elucidate the mechanisms involved in developing of CRC. Clinical studies have shown the importance of early prevention, detection and management of CRC in patients with UC, and colonoscopic surveillance at regular intervals with multiple biopsies is considered the most effective way. The use of endoscopy with targeted biopsies of visible lesions has been supported in most populations. In contrast, random biopsies in patients with high-risk characteristics have been suggested during surveillance. Some of the agents used to treat UC are chemopreventive, the effects of which will be examined in cancers in UC in a population-based setting. In this review, we outline the current state of potential risk factors and chemopreventive recommendations in UC-CRC, with a specific focus on the proinflammatory mechanisms in promoting CRC and evidence for personalized surveillance.
... High-definition white light endoscopy was introduced in 1993 and is the current standard in gastrointestinal (GI) endoscopic practice and has replaced standard-definition video endoscopy and is required for participation in IBD clinical trials because the image quality is demonstrably better. 13 However, we are concerned that several image vendors do not actually make high-definition videos available to the central readers, instead videos are downsampled to mediocre resolutions of 640 × 424 pixels for reasons that are unclear. ...
Central reading, that is, independent, off-site, blinded review or reading of imaging endpoints, has been identified as a crucial component in the conduct and analysis of inflammatory bowel disease clinical trials. Central reading is the final step in a workflow that has many parts, all of which can be improved. Furthermore, the best reading algorithm and the most intensive central reader training cannot make up for deficiencies in the acquisition stage (clinical trial endoscopy) or improve on the limitations of the underlying score (outcome instrument). In this review, academic and industry experts review scoring systems, and propose a theoretical framework for central reading that predicts when improvements in statistical power, affecting trial size and chances of success, can be expected: Multireader models can be conceptualised as statistical or non-statistical (social). Important organisational and operational factors, such as training and retraining of readers, optimal bowel preparation for colonoscopy, video quality, optimal or at least acceptable read duration times and other quality control matters, are addressed as well. The theory and practice of central reading and the conduct of endoscopy in clinical trials are interdisciplinary topics that should be of interest to many, regulators, clinical trial experts, gastroenterology societies and those in the academic community who endeavour to develop new scoring systems using traditional and machine learning approaches.
Gastrointestinal disease is prevalent and broad, manifesting itself in a variety of ways, including inflammation, fibrosis, infection, and cancer. However, historically, diagnostic technologies have exhibited limitations, especially with regard to diagnostic uncertainty. Despite development of newly emerging technologies such as optoacoustic imaging, many recent advancements have focused on improving upon pre-existing modalities such as ultrasound, computed tomography, magnetic resonance imaging, and endoscopy. These advancements include utilization of machine learning models, biomarkers, new technological applications such as diffusion weighted imaging, and new techniques such as transrectal ultrasound. This review discusses assessment of disease processes using imaging strategies for the detection and monitoring of inflammation, fibrosis, and cancer in the context of gastrointestinal disease. Specifically, we include ulcerative colitis, Crohn’s disease, diverticulitis, celiac disease, graft vs. host disease, intestinal fibrosis, colorectal stricture, gastric cancer, and colorectal cancer. We address some of the most recent and promising advancements for improvement of gastrointestinal imaging, including unique discussions of such advancements with regard to imaging of fibrosis and differentiation between similar disease processes.
This chapter describes important acute and chronic inflammatory lesions of the intestine, along with immunodeficiency diseases and vascular and drug-induced lesions of the bowel. This chapter highlights the epidemiology of these important groups of diseases, their common locations, gross and microscopic pathologies, approach to diagnosis, and differentials to consider before a diagnosis is made. This chapter brings out essential lucid descriptions of these lesions and diagnostic tips for the readers.
Optical imaging offers a high potential for noninvasive detection and therapy of cancer in humans. Recent advances in instrumentation for diffuse optical imaging have led to new capabilities for the detection of cancer in highly scattering tissue such as the female breast. In particular, fluorescence imaging was made applicable as a sensitive technique to image molecular probes in vivo. We review recent developments in the detection of breast cancer and fluorescence-guided surgery of the breast by contrast agents available for application on humans. Detection of cancer has been investigated with the unspecific contrast agents “indocyanine green” and “omocianine” so far. Hereby, indocyanine green was found to offer high potential for the differentiation of malignant and benign lesions by exploiting vessel permeability for macromolecules as a cancer-specific feature. Tumor-specific molecular targeting and activatable probes have been investigated in clinical trials for fluorescence-guided tumor margin detection. In this application, high spatial resolution can be achieved, since tumor regions are visualized mainly at the tissue surface. As another example of superficial tumor tissue, imaging of lesions in the gastrointestinal tract is discussed. Promising results have been obtained on high-risk patients with Barrett´s esophagus and with ulcerative colitis by administering 5-aminolevulinic acid which induces accumulation of protoporphyrin IX serving as a tumor-specific fluorescent marker. Time-gated fluorescence imaging and spectroscopy are effective ways to suppress underlying background from tissue autofluorescence. Furthermore, recently developed tumor-specific molecular probes have been demonstrated to be superior to white-light endoscopy offering new ways for early detection of malignancies in the gastrointestinal tract.
Background:
International guidelines recommend dysplasia surveillance in IBD.
Aim:
To compare endoscopic techniques for dysplasia surveillance METHODS: We searched MEDLINE, Embase, CENTRAL for randomised trials through May 2019. We estimated odds ratios (ORs) for binary and mean differences (MDs) for continuous outcomes, using frequentist random-effects network meta-analysis. We assessed study risk of bias and appraised evidence certainty using GRADE.
Results:
Eighteen trials (2638 participants) were included. Standard definition white-light endoscopy (OR 0.44, 95% CI 0.26-0.73; high certainty) and i-SCAN (OR 0.47, 95% CI 0.25-0.90; moderate certainty) had lower odds of detecting neoplasia than chromoendoscopy. Fujinon intelligent colour enhancement (FICE), standard definition white-light endoscopy and i-SCAN had lower odds for this outcome than full spectrum high definition white-light endoscopy (ORs 0.02 to 0.15; low certainty). Standard definition white-light endoscopy had lower odds of detecting nonpolypoid neoplasia than full spectrum high definition white-light endoscopy, narrow band imaging, chromoendoscopy and high definition white-light endoscopy (ORs 0.01-0.14; moderate certainty). Full spectrum high definition white-light endoscopy ranked as the best technique for both outcomes (moderate certainty). Standard definition white-light endoscopy had lower odds of detecting neoplasia by target biopsy (OR 0.27, 95% CI 0.08-0.91) and had shorter procedure time (MD -14.81 minutes, 95% CI -25.03, -4.06) than chromoendoscopy (moderate certainty).
Conclusions:
Chromoendoscopy, high definition white-light endoscopy, narrow band imaging, autofluorescence, FICE and full spectrum high definition white-light endoscopy may be comparable for dysplasia surveillance. Standard definition white-light endoscopy and i-SCAN probably provide lower yields for neoplasia identification. Full spectrum high definition white-light endoscopy may represent the first-line approach.
