Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Study compares narrow band imaging to chromoendoscopy for the detection of dysplasia in IBD patients

A new study from Spain finds that narrow band imaging appears to be a less time-consuming and equally effective alternative to chromoendoscopy for the detection of dysplasia (abnormal growths) in patients with long-standing inflammatory bowel disease.

However, this study demonstrated higher miss rates for detection of lesions by narrow band imaging as compared with chromoendoscopy, and the authors concluded that narrow band imaging cannot be recommended as the standard technique. The study appears in the October issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).

Inflammatory bowel disease (IBD) is the general name for diseases that cause inflammation in the small intestine and colon, which include Crohn's disease and ulcerative colitis. IBD patients are at high risk for developing dysplasia and colorectal cancer. Chromoendoscopy (CE) is used for dysplasia surveillance in IBD patients. It is a special technique used in conjunction with endoscopy to improve visualization of the mucosa or lining of the intestine and can help the endoscopist find abnormalities that are present during the endoscopic examination which may be difficult to identify using only "white light" endoscopy. Chromoendoscopy is performed by spraying specialized nonpermanent stains or dyes on the lining of the intestine during the endoscopic procedure.

Narrow band imaging (NBI) with endoscopy offers the potential for improved visualization and was developed to enhance certain mucosal or vascular characteristics so that abnormal growths are visualized better. It uses a special filter to illuminate tissue in the lining of the intestines with light at specific wavelengths, which enhances underlying vasculature and produces the greatest contrast between the vessels and surrounding mucosa. This can help the endoscopist see the margins of an abnormal growth better and assist in determining which areas are the best to biopsy.

"In recent years, several studies have shown that chromoendoscopy is more accurate in detecting dysplasia in patients with long-standing inflammatory bowel disease than conventional endoscopy," said study lead author Maria Pellisé, MD, Gastroenterology Department, Institut de Malalties Digestives I Metabòliques, CIBERehd Hospital Clinic, Barcelona, Spain. "The aim of this study was to compare new-generation NBI systems with high-resolution imaging with CE for the early detection of colitis-associated dysplasia and cancer in patients with long-standing colonic IBD. We found that NBI is a useful technique for the detection of dysplasia in patients with long-standing IBD that offers several advantages including efficiency, ease of use, and agility. However, the relatively high rate of missed lesions with NBI prevents its recommendation as the new standard technique of use."


Consecutive patients with clinically inactive, long-standing ulcerative colitis involving at least the left colon or patients with colonic Crohn's disease affecting at least one third of the colon were recruited from the Outpatient Clinic of the Gastroenterology Department at Hospital Clinic, Barcelona, Spain. A total of 60 patients were included in the prospective, randomized, crossover study.

Each patient underwent high-resolution NBI colonoscopy and high-resolution indigo carmine CE with an interval of three to eight weeks between procedures. The order in which the examinations were performed was randomized (1:1). All colonoscopies were conducted by one of two experienced endoscopists who were blinded to the endoscopic and histological findings obtained during the first procedure. The morphology, size and location of any visible lesion were recorded. Any suspicious lesions detected during the examinations were sampled or immediately removed after detection. Biopsy samples were processed and stained by using standard methods and were subsequently evaluated by an experienced gastrointestinal pathologist.


Chromoendoscopy identified 208 suspicious lesions and 12 dysplastic lesions, while NBI detected 136 suspicious lesions and 10 dysplastic lesions. Therefore, CE identified 50 percent more "suspicious" lesions, for a 20 percent incremental yield. The prevalence of dysplastic lesions among patients enrolled in the study was 21.7 percent. The percentage of missed neoplastic lesions was higher with NBI than with CE (31.8 percent vs. 13.6 percent), resulting in a miss rate risk difference of 18.2 percent. Mean withdrawal time of the endoscope for CE was significantly longer than that for NBI (26.87 minutes vs. 15.74 minutes).

The researchers concluded that NBI appears to be a less time-consuming and an equally effective alternative to CE for the detection of neoplasia, but with a higher miss rate, and so NBI cannot be recommended as the standard technique. As a consequence, they believe that CE should still be considered the technique of choice for detecting dysplasia in patients with long-standing IBD.

In an accompanying editorial, Charles N. Bernstein, MD, Department of Internal Medicine and IBD Clinical Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada, stated, "Pellise et al found a high rate of 22 percent of patients having dysplastic lesions, further promoting the value of color contrast endoscopy in searching for dysplasia, at least in the hands of an expert center prepared to biopsy up to 6 raised lesions per case. Contrary to the actual study conclusions, it seems to show a comparable merit of NBI to chromoendoscopy and a greater time efficiency. More studies of NBI in dysplasia surveillance in inflammatory bowel disease may clarify its role. However, even simpler than NBI might be white-light endoscopy with high-definition colonoscopes. For an incremental yield of finding dysplastic lesions, a study needs to be conducted to compare chromoendoscopy with white-light endoscopy with these newer generation and already widely used colonoscopes."

About the American Society for Gastrointestinal Endoscopy

Since its founding in 1941, the American Society for Gastrointestinal Endoscopy (ASGE) has been dedicated to advancing patient care and digestive health by promoting excellence in gastrointestinal endoscopy. ASGE, with nearly 12,000 members worldwide, promotes the highest standards for endoscopic training and practice, fosters endoscopic research, recognizes distinguished contributions to endoscopy, and is the foremost resource for endoscopic education. Visit and for more information and to find a qualified doctor in your area.

About Endoscopy

Endoscopy is performed by specially-trained physicians called endoscopists using the most current technology to diagnose and treat diseases of the gastrointestinal tract. Using flexible, thin tubes called endoscopes, endoscopists are able to access the human digestive tract without incisions via natural orifices. Endoscopes are designed with high-intensity lighting and fitted with precision devices that allow viewing and treatment of the gastrointestinal system.

Anne Brownsey | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>