China
Africa
Explore chapters and articles related to this topic
Telescopes for Inner Space: Fiber Optics and Endoscopes
Published in Suzanne Amador Kane, Boris A. Gelman, Introduction to Physics in Modern Medicine, 2020
Suzanne Amador Kane, Boris A. Gelman
New developments in endoscopic imaging are aimed at improving the images available. For example, chromoendoscopy involves the uses of stains or pigments introduced to distinguish the appearance of polyps or other abnormal features from normal tissues. Narrow Band Imaging involves using optical filters (Chapter 3) to change the way colors are imaged, resulting in better detection of fine blood vessels, features useful in classifying polyps, for example.
Cancer in IBD
Published in Peter Sagar, Andrew G. Hill, Charles H. Knowles, Stefan Post, Willem A. Bemelman, Patricia L. Roberts, Susan Galandiuk, John R.T. Monson, Michael R.B. Keighley, Norman S. Williams, Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2019
In the current literature, it is debated whether chromoendoscopy remains superior over white light endoscopy since the quality of white-light imaging is improved with the availability of high-definition endoscopes.36 Based on different trials not proving superiority of white light over chromoendoscopy, guidelines state that these two entities provide different functions: chromoendoscopy provides better contrast and high definition provides better resolution. Guidelines state that the two techniques are therefore complementary rather than interchangeable.1,2 However, an important factor to take into account when interpreting the literature is that all available studies evaluating the superiority of chromoendoscopy over white light endoscopy were performed in the era before the availability of high definition colonoscopy. Whether chromoendoscopy remains superior when compared to high definition white light endoscopy remains to be confirmed in a trial comparing high definition white light endoscopy with and without additional chromoendoscopy with respect to dysplasia yield. Furthermore, implementation of the dye technique in many general hospitals is poor. For many endoscopists, this technique requiring training and practice, is not a daily routine.1 Also, it requires equipment (spray-cathether and dye) that might not be available. These factors impose a risk that endoscopists are more occupied with carrying out the technique than performing careful inspection. A roadmap for implementation of the technique was proposed.37
Gastrointestinal Endoscopy
Published in Professor Sir Norman Williams, Professor P. Ronan O’Connell, Professor Andrew W. McCaskie, Bailey & Love's Short Practice of Surgery, 2018
Professor Sir Norman Williams, Professor P. Ronan O’Connell, Professor Andrew W. McCaskie
The ability to enhance lesion detection and achieve nearpatient discrimination of pathology without the need for histology is a common theme of several active areas of endoscopic development. The goal is to allow accurate discrimination of dysplasia grade in areas of Barrett’s oesophagus or quiescent ulcerative colitis and to aid polyp detection and the recognition of early gastric and colorectal cancer. The most widely available technique is chromoendoscopy, which involves the topical application of stains or pigments to improve tissue localisation, characterisation or diagnosis. Several agents have been described, which can broadly be categorised as absorptive (vital) stains such as methylene blue; contrast (reactive) stains, such as indigo carmine; and those used for tattooing, such as India ink. Acetic acid can be used to improve dysplasia detection in Barrett’s oesophagus and Lugol’s iodine can be useful in detecting early squamous cell carcinoma.
Performance of chromoendoscopy and narrow-band imaging in the diagnosis of gastric intestinal metaplasia
Published in Scandinavian Journal of Gastroenterology, 2022
Nhu Thi Hanh Vu, Duc Trong Quach, Ngoc Le Bich Dang, Quang Dinh Le, Doan Thi Nha Nguyen, Huy Minh Le, Nhan Quang Le, Toru Hiyama
Several new imaging techniques to overcome the limitations of traditional WLE have been developed over recent decades. Chromoendoscopy or tissue staining helps to observe the subtle lesions as it enhances the mucosal surface characteristics of the gastric epithelium. This leads to an increase in the endoscopic diagnostic accuracy of premalignant lesions [6–8]. Besides, narrow-band imaging (NBI) is an optical image improvement technology that uses two short-wavelength light beams of 415 nm (blue) and 540 nm (green) [9]. NBI has the potential to improve the visualization of microvascular architecture and microsurface structure between the epithelial surface and subjacent vascular pattern [10]. Several studies have described the diagnostic accuracy of NBI in detecting gastrointestinal lesions [11]. Based on these results, the use of chromoendoscopy and NBI techniques for targeted biopsy sampling can increase the diagnostic yield of endoscopy for the detection of pre-malignant gastric lesions.
Dysplasia in the mucosal biopsy specimen is still a warning sign of cancer in ulcerative colitis
Published in Scandinavian Journal of Gastroenterology, 2020
Essi K. Karjalainen, Laura Renkonen-Sinisalo, Anna H. Lepistö
In our patient cohort, a great proportion of dysplastic lesions were not identified before surgery. More importantly, 17% of the patients who underwent surgery because of the dysplasia only, showed cancer in the specimen. It is already clear that dysplasia detection in standard colonoscopy with random biopsies is very poor [12]. More advanced techniques including dye-based chromoendoscopy and virtual chromoendoscopy such as narrow-band imaging have proven more efficient in detecting dysplasia and are recommended by the ECCO Guidelines [4,13]. In our endoscopy unit, the use of dye-based chromoendoscopy is increasing, but the majority of surveillance colonoscopies are still standard colonoscopies. The significance of dysplasia in UC has been under debate, with suggestions recently provided concerning the endoscopic management of lesions. However, the fact that the endoscopic recognition of dysplasia and even of cancer in UC is still far from optimal means that indications for surgery should perhaps not be altered.
Outcome after endoscopic treatment for dysplasia and superficial esophageal cancer – a cohort study
Published in Scandinavian Journal of Gastroenterology, 2020
Tobias Hauge, Isabel Franco-Lie, Else Marit Løberg, Truls Hauge, Egil Johnson
All procedures were conducted by three consultants at the department of gastroenterology. The senior consultant, having 20 years of experience in multiband EMR in the esophagus, supervised the two other consultants. EMR was performed under intravenous sedation (midazolam and alfentanil), while the majority of patients undergoing RFA had deep sedation (propofol) under supervision of an anesthesiologist. Both procedures were mainly undertaken in an outpatient setting. The upper endoscopy was performed with standard white light as well as chromoendoscopy with diluted vinegar and narrow-banding imaging (NBI). Tumors found to be superficial and feasible for endoscopic removal were removed using multiband EMR. In two cases, endoscopic submucosal dissection (ESD) was performed. After a minimum of six weeks, Barrett’s epithelium was eradicated with RFA using Barrx with the 360 RFA balloon and in some cases the focal catheter (Medtronic, Dublin, Ireland). Those who had solely dysplastic changes without a visible tumor, underwent RFA only. The number of treatments was recorded as well as their histological and visual outcome.