The unmet needs for identifying the ideal bowel preparation.

Colonoscopy, since it was first employed over 60 years ago, is now the gold standard method for visualizing the mucosa of the colon, but should be of good quality. Many factors affect quality, including the type of health service organization, type of facility, staff, equipment, patient characteristics, and bowel preparation (BP). The adequacy of bowel cleansing is critical, but, unfortunately, may be inadequate in up to one-third of procedures. The current article will present and discuss the main BPs and their drawbacks, which include patient-dependent and procedure-dependent factors. Cleansing quality depends on the ease/complexity of solution preparation, volume, taste, and timing of consumption. Consequently, important positive factors include simple instructions, easy preparation of the solution, low volume, pleasant taste, short drinking time (e.g. <30 min), and splitting the dose between the evening before and the morning of the colonoscopy (or even better, only one dose in the early morning to avoid night-time problems), and short onset of action. The BP solution must also be safe with negligible side effects. Furthermore, a positive experience supports patient willingness to repeat the procedure.

European guidelines on microscopic colitis: United European Gastroenterology and European Microscopic Colitis Group statements and recommendations.

INTRODUCTION: Microscopic colitis is a chronic inflammatory bowel disease characterised by normal or almost normal endoscopic appearance of the colon, chronic watery, nonbloody diarrhoea and distinct histological abnormalities, which identify three histological subtypes, the collagenous colitis, the lymphocytic colitis and the incomplete microscopic colitis. With ongoing uncertainties and new developments in the clinical management of microscopic colitis, there is a need for evidence-based guidelines to improve the medical care of patients suffering from this disorder. METHODS: Guidelines were developed by members from the European Microscopic Colitis Group and United European Gastroenterology in accordance with the Appraisal of Guidelines for Research and Evaluation II instrument. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists, pathologists and basic scientists, and voted upon using the Delphi method. RESULTS: These guidelines provide information on epidemiology and risk factors of microscopic colitis, as well as evidence-based statements and recommendations on diagnostic criteria and treatment options, including oral budesonide, bile acid binders, immunomodulators and biologics. Recommendations on the clinical management of microscopic colitis are provided based on evidence, expert opinion and best clinical practice. CONCLUSION: These guidelines may support clinicians worldwide to improve the clinical management of patients with microscopic colitis.

Panenteric capsule endoscopy identifies proximal small bowel disease guiding upstaging and treatment intensification in Crohn's disease: A European multicentre observational cohort study.

BACKGROUND: Endoscopically defined mucosal healing in Crohn's disease is associated with improved outcomes. Panenteric capsule endoscopy enables a single non-invasive assessment of small and large bowel mucosal inflammation. AIMS AND METHODS: This multicentre observational study of patients with suspected and established Crohn's disease examined the feasibility, safety and impact on patient outcomes of panenteric capsule endoscopy in routine clinical practice. The potential role in assessment of disease severity and extent by a comparison with existing clinical and biochemical markers is examined. RESULTS: Panenteric capsule endoscopy was performed on 93 patients (71 with established and 22 with suspected Crohn's disease). A complete examination occurred in 85% (79/93). Two cases (2.8%) of capsule retention occurred in patients with established Crohn's disease. Panenteric capsule resulted in management change in 38.7% (36/93) patients, including 64.6% (32/48) of those with an established diagnosis whose disease was active, and all three patients with newly diagnosed Crohn's disease. Montreal classification was upstaged in 33.8% of patients with established Crohn's disease and mucosal healing was demonstrated in 15.5%. Proximal small bowel disease upstaged disease in 12.7% and predicted escalation of therapy (odds ratio 40.3, 95% confidence interval 3.6-450.2). Raised C-reactive protein and faecal calprotectin were poorly sensitive in detecting active disease (0.48 and 0.59 respectively). CONCLUSIONS: Panenteric capsule endoscopy was feasible in routine practice and the ability to detect proximal small bowel disease may allow better estimation of prognosis and guide treatment intensification. Panenteric capsule endoscopy may be a suitable non-invasive endoscopic investigation in determining disease activity and supporting management decisions.

Feasibility Trial of the Newly Introduced Optical Enhancement Technology in Patients with Gastroesophageal Reflux Disease.

BACKGROUND: Optical Enhancement technology (OE) combines bandwidth-limited light and image enhancement processing technology to enhance subtle mucosal and vascular details. This is the first study assessing the new technology for the diagnosis of gastroesophageal reflux disease (GERD). PATIENTS AND METHODS: Consecutive patients with GERD and controls were prospectively included. The distal esophagus was examined in all quadrants with high definition white-light endoscopy (HD-WLE) followed by OE and biopsies for histopathological analysis. Features observed only by OE were compared between controls and patients with GERD. RESULTS: A total of 100 areas were evaluated. About 56% of patients had a diagnosis of GERD. The mean age of patients was 53 years (range 27-89 years), 60% were female. Compared to controls, patients with diagnosis of GERD showed significantly more often tortuosity (p = 0.042), dilation (p = 0.0003), and increased number (p = 0.001) of intrapapillary capillary loops (IPCLs). In addition, increased vascularity and mucosal breaks were significantly more often found in patients with GERD as compared to controls (p < 0.05). On multivariate analysis, increased number and dilation of IPCL were the best predictors of GERD. CONCLUSIONS: The newly introduced OE technology significantly improves the diagnosis of GERD compared to HD-WLE. The results should be confirmed in a multicenter trial.

I-scan optical enhancement for the in vivo prediction of diminutive colorectal polyp histology: Results from a prospective three-phased multicentre trial.

BACKGROUND AND AIMS: Dye-less chromoendoscopy is an emerging technology for colorectal polyp characterization. Herein, we investigated whether the newly introduced I-scan optical enhancement (OE) can accurately predict polyp histology in vivo in real-time. METHODS: In this prospective three-phased study, 84 patients with 230 diminutive colorectal polyps were included. During the first two study phases, five endoscopists assessed whether analysis of polyp colour, surface and vascular pattern under i-scan OE can differentiate in vivo between adenomatous and hyperplastic polyps. Finally, junior and experienced endoscopists (JE, EE, each n = 4) not involved in the prior study phases made a post hoc diagnosis of polyp histology using a static i-scan OE image database. Histopathology was used as a gold-standard in all study phases. RESULTS: The overall accuracy of i-scan OE for histology prediction was 90% with a sensitivity, specificity, positive (PPV) and negative prediction value (NPV) of 91%, 90%, 86% and 94%, respectively. In high confidence predictions, the diagnostic accuracy increased to 93% with sensitivity, specificity, PPV and NPV of 94%, 91%, 89% and 96%. Colonoscopy surveillance intervals were predicted correctly in ≥ 90% of patients. In the post hoc analysis EE predicted polyp histology under i-scan OE with an overall accuracy of 91%. After a single training session, JE achieved a comparable diagnostic performance for predicting polyp histology with i-scan OE. CONCLUSION: The histology of diminutive colorectal polyps can be accurately predicted with i-scan OE in vivo in real-time. Furthermore, polyp differentiation with i-scan OE appears to require only a short learning curve.

Thulium laser in interventional endoscopy: animal and human studies.

Background and study aims The thulium laser system (TLS) is an emerging surgical tool. The 2-µm wavelength provides a confined coagulation depth (0.2 - 0.4 mm) to reduce the potential for inadvertent injuries. For the first time ever, we assessed TLS feasibility for endoscopic hemostasis ex vivo in pigs. In addition, we performed the first in vivo hemostatic treatments in humans. Patients and methods Tissue damage induced by TLS using different settings and optical fibers was compared to that from argon plasma coagulation (APC) in established ex vivo animal models. Three consecutive patients with complex nonvariceal upper gastrointestinal bleedings were treated and followed up. Results No deep submucosal injury was observed in animal models. The TLS showed a progressive penetration depth with increased power outputs and tissue exposures but very limited vertical tissue injury (0.1 - 2.0 mm) and lateral spreading damage (0.1 - 0.3 mm and 0.2 - 0.7 mm using the 365-µm and 550-µm fibers, respectively). In vivo, endoscopic hemostasis with TLS was always successful without complications. Conclusions The TLS has proven to be very precise and easy to use. This novel technique appears to be a promising tool for advanced interventional endoscopy.

In vivo real-time assessment of colorectal polyp histology using an optical biopsy forceps system based on laser-induced fluorescence spectroscopy.

BACKGROUND AND STUDY AIMS: In order to reduce time, costs, and risks associated with resection of diminutive colorectal polyps, the American Society for Gastrointestinal Endoscopy (ASGE) recently proposed performance thresholds that new technologies should meet for the accurate real-time assessment of histology of colorectal polyps. In this study, we prospectively assessed whether laser-induced fluorescence spectroscopy (LIFS), using the new WavSTAT4 optical biopsy system, can meet the ASGE criteria. PATIENTS AND METHODS: 27 patients undergoing screening or surveillance colonoscopy were included. The histology of 137 diminutive colorectal polyps was predicted in real time using LIFS and findings were compared with the results of conventional histopathological examination. The accuracy of predicting polyp histology with WavSTAT4 was assessed according to the ASGE criteria. RESULTS: The overall accuracy of LIFS using WavSTAT4 for predicting polyp histology was 84.7 % with sensitivity, specificity, and negative predictive value (NPV) of 81.8 %, 85.2 %, and 96.1 %. When only distal colorectal diminutive polyps were considered, the NPV for excluding adenomatous histology increased to 100 % (accuracy 82.4 %, sensitivity 100 %, specificity 80.6 %). On-site, LIFS correctly predicted the recommended surveillance intervals with an accuracy of 88.9 % (24/27 patients) when compared with histology-based United States guideline recommendations; in the 3 patients for whom LIFS- and histopathology-based recommended surveillance intervals differed, LIFS predicted shorter surveillance intervals. CONCLUSIONS: From the data of this pilot study, LIFS using the WavSTAT4 system appears accurate enough to allow distal colorectal polyps to be left in place and nearly reaches the threshold to "resect and discard" them without pathologic assessment. WavSTAT4 therefore has the potential to reduce costs and risks associated with the removal of diminutive colorectal polyps.

High-definition endoscopy with digital chromoendoscopy for histologic prediction of distal colorectal polyps.

BACKGROUND: Distal diminutive colorectal polyps are common and accurate endoscopic prediction of hyperplastic or adenomatous polyp histology could reduce procedural time, costs and potential risks associated with the resection. Within this study we assessed whether digital chromoendoscopy can accurately predict the histology of distal diminutive colorectal polyps according to the ASGE PIVI statement. METHODS: In this prospective cohort study, 224 consecutive patients undergoing screening or surveillance colonoscopy were included. Real time histology of 121 diminutive distal colorectal polyps was evaluated using high-definition endoscopy with digital chromoendoscopy and the accuracy of predicting histology with digital chromoendoscopy was assessed. RESULTS: The overall accuracy of digital chromoendoscopy for prediction of adenomatous polyp histology was 90.1 %. Sensitivity, specificity, positive and negative predictive values were 93.3, 88.7, 88.7, and 93.2 %, respectively. In high-confidence predictions, the accuracy increased to 96.3 % while sensitivity, specificity, positive and negative predictive values were calculated as 98.1, 94.4, 94.5, and 98.1 %, respectively. Surveillance intervals with digital chromoendoscopy were correctly predicted with >90 % accuracy. CONCLUSIONS: High-definition endoscopy in combination with digital chromoendoscopy allowed real-time in vivo prediction of distal colorectal polyp histology and is accurate enough to leave distal colorectal polyps in place without resection or to resect and discard them without pathologic assessment. This approach has the potential to reduce costs and risks associated with the redundant removal of diminutive colorectal polyps. TRIAL REGISTRATION: ClinicalTrials NCT02217449.