Standard Video Endoscopy Research Articles

Assessment of the Relation between Serum Carcinoembryonic Antigen and Tumor Node Metastasis Staging of Colorectal Cancer

Background: Although awareness via cancer screenings and the knowledge of therapy modalities has increased, the burden of colorectal cancer (CRC) is much more pronounced in developing countries. Objective: This study was aimed to estimate serum carcinoembryonic antigen (CEA) levels in preoperative CRC patients and to determine the associations between serum CEA levels and tumor node metastasis (TNM) stage. Patients and methods: This cross-sectional study included 36 patients with CRC (stages IV) attending at Department of General Surgery, Zagazig University Hospitals. Patients scheduled preoperatively for sigmoidoscopy were prepared by an enema and examined by using standard video endoscopes. The CEA levels were estimated preoperatively for all patients. Results: CEA level among the studied cases ranged from 0 to 23 ng/dl with mean 6.39 ng/dl and median 4.5ng/ml. Also 58.3% had CEA level ≤ 5 ng/ml. There were no statistical significance relations between the CEA and age or sex distribution. But there was a statistical significance increase in frequency of smoking among cases had CEA level >5 ng/ml. There was no statistical significance relation between site and diameter of lesions and CEA level among the studied cases. Conclusions: It could be concluded that there is a meaningful link between TNM stage and CEA level. However, normal levels of CEA will not rule out CRC diagnosis, and these patients should be investigated in detail.

Coregistered optical coherence tomography and frequency-encoded multispectral imaging for spectrally sparse color imaging.

.We present a system combining optical coherence tomography (OCT) and multispectral imaging (MSI) for coregistered structural imaging and surface color imaging. We first describe and numerically validate an optimization model to guide the selection of the MSI wavelengths and their relative intensities. We then demonstrate the integration of this model into an all-fiber bench-top system. We implement frequency-domain multiplexing for the MSI to enable concurrent acquisition of both OCT and MSI at OCT acquisition rates. Such a system could be implemented in endoscopic practices to provide multimodal, high-resolution imaging of deep organ structures that are currently inaccessible to standard video endoscopes.

Endoscopic Findings Related To Helicobacter Pylori

Background: Studies with the latest technologies such as endoscopy with magnification and chromoendoscopy showed that various endoscopic aspects are clearly related to infection by Helicobacter pylori (Hp). The description of different patterns of erythema in gastric body under magnification of images revived interest in identifying these patterns by standard endoscopy. Aim: To validate the morphologic features of gastric mucosa to conventional gastroscopy Hprelated gastritis allowing predictability of their diagnosis as well as proper targeting biopsies. Methods: Prospective study of 339 consecutive patients with the standard videoendoscope image analysis were obtained, recorded and stored in a program database. These images were studied with respect to the presence or absence of HP, diagnosed by rapid urease test and/or by histological analysis. Were studied: a) normal mucosa appearance; b) mucosal nodularity; c) diffuse nonspecific erythemaor redness of antrum and body; d) mosaic pattern with focal area of hyperemia; e) erythema in streaks or bands (red streaks); f) raised erosions; g) flat erosions; h) fundic gland polyps. The main exclusion criteria were the use of drugs, Hp pre-treatment and other entities that could affect results. Results: Applying the exclusion criteria, were included 170 of the 339 patients, of which 52 (30.58%) were positive for Hp and 118 negative. On the positive findings, the most associated with infection were: antralnodularity (26.92%); raised erosion (15.38%) and mosaic pattern in the body (21,15%). On the negative group the normal appearance of the mucosa was 66.94%; red streaks in 9.32%; flat erosions 11.86%; and fundic gland polyps 11.86%. Conclusion: Endoscopic findings are useful in predicting the outcome, localization and targeting of biopsies in gastritis related to Helicobacter pylori infection.The most representative form of Hp related gastritis was the nodularity of the antralmucosa. Diffuse redness and mosaic pattern in the bodyare closely related to Hp infection.Raised erosions are suggestive but not specific to the infection. Normal-appearing forms, red streaks and fundic gland polyposis are related to the negativity of Helicobacter pylori infection. Flat erosions were not conclusive of the presence or absence of Hp.

CONVENTIONAL VIDEOENDOSCOPY CAN IDENTIFY HELICOBACTER PYLORI GASTRITIS?

ABSTRACTBackground: Studies with latest technologies such as endoscopy with magnification and chromoendoscopy showed that various endoscopic aspects are clearly related to infection by Helicobacter pylori (HP). The description of different patterns of erythema in gastric body under magnification of images revived interest in identifying these patterns by standard endoscopy. Aim:To validate the morphologic features of gastric mucosa related to H. pylori infection gastritis allowing predictability of their diagnosis as well as proper targeting biopsies. Methods: Prospective study of 339 consecutive patients with the standard videoendoscope image analysis were obtained, recorded and stored in a program database. These images were studied with respect to the presence or absence of H. pylori, diagnosed by rapid urease test and/or by histological analysis. Were studied: a) normal mucosa appearance; b) mucosal nodularity; c) diffuse nonspecific erythema or redness (with or without edema of folds and exudate) of antrum and body; d) mosaic pattern with focal area of hyperemia; e) erythema in streaks or bands (red streak); f) elevated (raised) erosion; g) flat erosions; h) fundic gland polyps. The main exclusion criteria were the use of drugs, HP pre-treatment and other entities that could affect results. Results: Applying the exclusion criteria, were included 170 of the 339 patients, of which 52 (30.58%) were positive for HP and 118 negative. On the positive findings, the most associated with infection were: nodularity in the antrum (26.92%); presence of raised erosion (15.38%) and mosaic mucosa in the body (21.15%). On the negative group the normal appearance of the mucosa was 66.94%; erythema in streaks or bands in 9.32%; flat erosions 11.86%; and fundic gland polyps 11.86%. Conclusion: Endoscopic findings are useful in the predictability of the result and in directing biopsies. The most representative form of HP related gastritis was the nodularity of the antral mucosa. The raised erosion and mucosa in mosaic in the body are suggestive but not specific to the infection. The other forms were not conclusive of the presence of HP.

Evaluation and Detection of Dysplasia in IBD: the Role of Chromoendoscopy and Enhanced Imaging Techniques.

Patients with ulcerative colitis (UC) and Crohn's disease (CD) colitis are at significantly higher risk for the development of colitis-associated colorectal cancer (CAC), a risk associated with increased duration and extent of disease [1]. CAC in patients with ulcerative colitis and Crohn's colitis arises from dysplastic tissue in the background of mucosal inflammatory changes. Regular surveillance by colonoscopy is a recommended cancer prevention strategy endorsed by the US and European GI societies [2-4]. Until recently, random sampling of the mucosa throughout the colon has been the mainstay of this conventional surveillance. This requires multiple biopsies to be taken and processed, a practice which is time consuming, expensive, and has a low diagnostic yield. The growth pattern of dysplastic tissue is often multifocal and diffuse, and thus, its detection may not be optimal with the use of traditional white light colonoscopy. According to recent studies, most dysplastic lesions appear to be visible to careful endoscopic inspection [5-7]. Thus, the approach focusing on targeted biopsies of any mucosal abnormalities instead of only random biopsies has been advocated [8]. In addition, the detection and further delineation of any mucosal abnormalities are thought to be improved by the application of dyes that highlight more subtle abnormalities known as chromoendoscopy (CE) as well as a new generation endoscopic system with high-definition white light endoscopy (HDWL). The application of CE in patients with long-term UC was deemed to be beneficial based upon the results of previous clinical trials comparing CE with standard definition white light endoscopy (SDWL) [9•, 10•]. However, there are limited data available comparing CE with the currently broadly used high-definition colonoscopies (HDWL) [11•, 12•, 13•]. High-definition (HD) endoscopy uses a high-definition monitor and a high-resolution CCD (charge-coupled device) providing images of substantially higher resolution than standard video endoscopy. Thus, HDWL colonoscopy may be an alternative to CE in IBD surveillance without the need for the extra time and required experience with CE. Further longitudinal studies are necessary to determine the ultimate advantage of chromoendoscopy or lack of the advantages of chromoendoscopy over that of high-definition colonoscopy in detection of dysplasia. Once lesions are identified by HDWL and CE, they can be further evaluated with evolving technologies to perform in vivo microscopy. Small-field technologies such as confocal endomicroscopy (CLE) permit in vivo microscopic assessment of the colonic mucosa. This evolving technology can be utilized in combination with HDWL and CE in selected cases to further define the lesions and assess their histology, and thus, facilitate real-time in vivo diagnosis and decisions regarding resection of lesions. Further studies to determine the applicability of these newer enhanced technologies in evaluation of dysplasia in routine clinical practice are needed.

Imaging the Upper Gastrointestinal Tract in Unsedated Patients Using Tethered Capsule Endomicroscopy

Endoscopic examination of the upper gastrointestinal tract is costly, inconvenient, and typically requires that the patient be sedated.1 Standard video endoscopy only provides macroscopic information so small, focal biopsies are excised in order to obtain a microscopic tissue diagnosis. Because there are few reliable visible cues for Barrett’s esophagus and dysplasia, crucial diagnostic regions can be missed. In order to overcome these limitations of endoscopy, we have integrated a microscopic imaging technology into a tethered capsule that can be swallowed. This new method, which we term tethered capsule endomicroscopy, provides microscopic information from the entire esophagus as the pill passes through the GI tract.

A 25-mm diameter probe for photoacoustic and ultrasonic endoscopy

We have created a 2.5-mm outer diameter integrated photo-acoustic and ultrasonic mini-probe which can be inserted into a standard video endoscope's instrument channel. A small-diameter focused ultrasonic transducer made of PMN-PT provides adequate signal sensitivity, and enables miniaturization of the probe. Additionally, this new endoscopic probe utilizes the same scanning mirror and micromotor-based built-in actuator described in our previous reports; however, the length of the rigid distal section of the new probe has been further reduced to ~35 mm. This paper describes the technical details of the mini-probe and presents experimental results that both quantify the imaging performance and demonstrate its in vivo imaging capability, which suggests that it could work as a mini-probe for certain clinical applications.

OC-014 High definition colonoscopes cause more pain and require more sedation than the standard video endoscope

IntroductionIt has been anecdotally observed in this centre, a tertiary teaching hospital, that high definition colonoscopes (HDC) seem to be more difficult to manoeuvre and cause more pain to the...

Blinded nonrandomized comparative study of gastric examination with a magnetically guided capsule endoscope and standard videoendoscope

Passive video capsule endoscopy is the criterion standard for small-bowel exploration but cannot be used for the large gastric cavity. We report the first blinded comparative clinical trial in humans comparing a magnetically guided capsule endoscope (MGCE) and a conventional high-definition gastroscope. To assess the potential of gastric examination with a guided capsule. Blinded, nonrandomized comparative study. Single endoscopy center. The trial involved 61 patients included in a blinded capsule and gastroscopy comparative study. MGCE examination was performed 24 hours after patients had undergone gastroscopy. To remove food residue or mucus, patients drank 900 mL of water in 2 portions. Then to provide the air-water interface required by the guidance system, they drank 400 mL of water at 35°C. Visualization of the gastric pylorus, antrum, body, fundus, and cardia was evaluated as complete in 88.5%, 86.9%, 93.4%, 85.2%, and 88.5% of patients, respectively. Of gastric lesions, 58.3% were detected by both gastroscopy and MGCE at immediate assessment and review of recorded data. Capsule examination missed 14 findings and gastroscopy missed 31 findings seen with MGCE. Overall diagnostic yield was similar for both modalities. Pilot study. Diagnostic results were similar for the 2 methods. After some technical difficulties related to gastric expansion or presence of mucus had been overcome, this study opened a new field for noninvasive gastric examination in countries where high gastric cancer incidence demands a screening tool.

Su1470 Is There Additional Benefit in Using Confocal Laser Endomicroscopy (CLE) Over Narrow Band Imaging (NBI) in Neoplasia Detection for Barrett's Esophagus (BE) Patients?

Confocal laser microscopy is an imaging technology that integrates a confocal laser microscope in the tip of a standard videoendoscope or as a probe that can be passed through the channel of any endoscope. The aim is to provide real-time histology, allowing high resolution in vivo histological assessment at subcellular resolution during endoscopy. NBI was developed primarily to emphasize the mucosal microvasculature and to identify vascular alterations indicative of dysplasia. The accuracy in reported studies for the detection of neoplasia for both modalities has been excellent.

Endoscopic Trimodal Imaging Detects Colonic Neoplasia as Well as Standard Video Endoscopy

Endoscopic trimodal imaging (ETMI) is a novel endoscopic technique that combines high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) that has only been studied in academic settings. We performed a randomized, controlled trial in a nonacademic setting to compare ETMI with standard video endoscopy (SVE) in the detection and differentiation of colorectal lesions. The study included 234 patients scheduled to receive colonoscopy who were randomly assigned to undergo a colonoscopy in tandem with either ETMI or SVE. In the ETMI group (n=118), first examination was performed using HRE, followed by AFI. In the other group, both examinations were performed using SVE (n=116). In the ETMI group, detected lesions were differentiated using AFI and NBI. In the ETMI group, 87 adenomas were detected in the first examination (with HRE), and then 34 adenomas were detected during second inspection (with AFI). In the SVE group, 79 adenomas were detected during the first inspection, and then 33 adenomas were detected during the second inspection. Adenoma detection rates did not differ significantly between the 2 groups (ETMI: 1.03 vs SVE: 0.97, P=.360). The adenoma miss-rate was 29% for HRE and 28% for SVE. The sensitivity, specificity, and accuracy of NBI in differentiating adenomas from nonadenomatous lesions were 87%, 63%, and 75%, respectively; corresponding values for AFI were 90%, 37%, and 62%, respectively. In a nonacademic setting, ETMI did not improve the detection rate for adenomas compared with SVE. NBI and AFI each differentiated colonic lesions with high levels of sensitivity but low levels of specificity.

High definition colonoscopy vs. standard video endoscopy for the detection of colonic polyps: a meta-analysis

High definition colonoscopy may improve adenoma detection rates but studies report conflicting results. The aim of this meta-analysis was to compare the diagnostic yield of colonic polyps between high definition colonoscopy and standard video endoscopy (SVE). Various electronic databases were searched for articles reporting on high definition colonoscopy. The pooled incremental yield and pooled weighted mean difference of high definition colonoscopy over SVE for polyp detection was determined. Five studies involving 4422 patients provided data on the total number of polyps detected. The incremental yield of high definition colonoscopy for the detection of any polyp was 3.8 % (95 % confidence interval [CI] 1 % - 6.7 %) with a number needed to treat (NNT) of 26. For the detection of adenomatous polyps the incremental yield was 3.5 % (95 %CI 0.9 % - 6.1 %) with an NNT of 28. There were no differences between high definition and SVE in the detection of high risk adenomas, with an incremental yield of -0.1 % (95 %CI -1.7 % to 1.6 %). When grouped according to the overall adenoma detection rate of the studies (> 50 % or < 50 %) the pooled weighted mean difference in small adenoma detection was better with high definition colonoscopy ( P = 0.035). There were marginal differences between high definition colonoscopy and SVE for the detection of colonic polyps/adenomas. High definition colonoscopy did not improve the detection of high risk adenomas. Due to differences in the adenoma detection rate between the studies and the nonrandomized study design of three of the five studies, these results need to be interpreted with caution. Prospective randomized trials looking at long term outcomes such as rates of interval or missed cancers are needed to clarify the clinical implications.

Endoscopic trimodal imaging versus standard video endoscopy for detection of early Barrett's neoplasia: a multicenter, randomized, crossover study in general practice

Endoscopic trimodal imaging (ETMI) may improve detection of early neoplasia in Barrett's esophagus (BE). Studies with ETMI so far have been performed in tertiary referral settings only. To compare ETMI with standard video endoscopy (SVE) for the detection of neoplasia in BE patients with an intermediate-risk profile. Multicenter, randomized, crossover study. Community practice. BE patients with confirmed low-grade intraepithelial neoplasia (LGIN) underwent both ETMI and SVE in random order (interval 6-16 weeks). During ETMI, BE was inspected with high-resolution endoscopy followed by autofluorescence imaging (AFI). All visible lesions were then inspected with narrow-band imaging. During ETMI and SVE, visible lesions were sampled followed by 4-quadrant random biopsies every 2 cm. Overall histological yield of ETMI and SVE and targeted histological yield of ETMI and SVE. A total of 99 patients (79 men, 63±10 years) underwent both procedures. ETMI had a significantly higher targeted histological yield because of additional detection of 22 lesions with LGIN/high-grade intraepithelial neoplasia (HGIN)/carcinoma (Ca) by AFI. There was no significant difference in the overall histological yield (targeted+random) between ETMI and SVE. HGIN/Ca was diagnosed only by random biopsies in 6 of 24 patients and 7 of 24 patients, with ETMI and SVE, respectively. Inspection, with high-resolution endoscopy and AFI, was performed sequentially. ETMI performed in a community-based setting did not improve the overall detection of dysplasia compared with SVE. The diagnosis of dysplasia is still being made in a significant number of patients by random biopsies. Patients with a confirmed diagnosis of LGIN have a significant risk of HGIN/Ca. ( ISRCTN91816824; NTR867.).

Endoscopic Tri-Modal Imaging Is More Effective Than Standard Endoscopy in Identifying Early-Stage Neoplasia in Barrett's Esophagus

Endoscopic tri-modal imaging (ETMI) incorporates high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow band imaging (NBI). A recent uncontrolled study found that ETMI improved the detection of high-grade dysplasia (HGD) and early carcinoma (Ca) in Barrett's esophagus (BE). The aim was to compare ETMI with standard video endoscopy (SVE) for the detection of HGD/Ca with the use of a randomized cross-over design. Patients referred for work-up of inconspicuous HGD/Ca were eligible and underwent both SVE and ETMI in randomized order within an interval of 6-12 weeks. During ETMI, inspection with HRE was followed by AFI. Detected lesions were inspected in detail with NBI and biopsied, followed by random biopsies. During SVE, any visible lesion was biopsied followed by random biopsies. Eighty-seven patients with BE underwent ETMI and SVE. No significant difference was observed in overall histologic yield between ETMI and SVE. ETMI had a significantly higher targeted yield compared with SVE because of AFI. However, the yield of targeted biopsies of ETMI was significantly inferior to the overall yield of SVE. Detailed inspection with NBI reduced the false-positive rate of HRE + AFI from 71% to 48% but misclassified 17% of HGD/Ca lesions as not suspicious. ETMI statistically significant improves the targeted detection of HGD/Ca compared with SVE. Subsequent characterization of lesions with NBI appears to be of limited value. At this stage, ETMI cannot replace random biopsies for detection of lesions or targeted biopsies for characterization of lesions in a high-risk population.

Confocal Laser Endomicroscopy: Technical Advances and Clinical Applications

Since its introduction in 2004, confocal laser endomicroscopy (CLE) has emerged as a valuable tool for gastrointestinal endoscopic imaging. Endomicroscopy enables the endoscopist to obtain real time in vivo histology during ongoing endoscopy thereby creating “optical biopsies.” To date, numerous studies have shown potential applications of endomicroscopy in the clinical setting, including in vivo diagnosis of esophageal squamous cell carcinoma, Barrett’s esophagus, celiac disease, and colonic polyps. Moreover, recent data suggest the potential application of endomicroscopy in the field of molecular imaging. Additionally, in recent months new applications and developments in the field of confocal imaging were introduced including endomicroscopy of the liver, pancreatic, and bile ducts. Furthermore, by introducing a new needle-based confocal imaging system, which is small enough to be introduced through a 22gauge puncture needle, a wide field for new applications of endomicroscopic imaging has been opened. Currently, 2 CE- and US Food and Drug Administration (FDA)approved devices for endomicroscopy are available (Figures 1 and 2; Supplementary Table 1). In this review, we introduce both systems and discuss new technical advances and clinical applications of CLE.

Blood Splash Injury: An Underestimated Risk in Endourology

Mucocutaneous and transconjunctival exposure are important portals for the transmission of blood-borne infections to surgeons and health-care workers. Despite this knowledge, few surgeons or their assistants wear protective equipment for procedures perceived to be affiliated with less risk. This study investigates the potential risk of mucocutaneous and transconjunctival blood splash injury during common laparoscopic and endourologic procedures undertaken using standard video endoscopy equipment. Masks combined with eye shields were consecutively collected from the surgeon, surgical assistant, and theater nurse after a variety of endourologic procedures over a 4-month period. These were analyzed macroscopically for visible blood droplets. Modern forensic techniques were then instituted to assess for nonvisible blood exposure. Eye shields from 118 procedures performed by five surgeons were collected. Two hundred and thirty-six masks were examined for visible and visually enhanced evidence of blood contamination. In total, 48.5% of surgeons' masks, 29.5% of assisting surgeons' masks, and 31.8% of scrub nurse masks were positive for either visible or visually enhanced blood contamination. In terms of evidence of blood splash, 84.2% of laparoscopic nephrectomies, 66.7% of pyeloplasties, and 58.3% of flexible ureteroscopies tested positive. Splash injuries remain commonplace, even with the use of video endoscopy equipment. Therefore, all health-care workers should be encouraged to wear eye and face protection when undertaking both endoscopic and laparoscopic urologic procedures. These observations may have broader implications relevant to all minimally invasive surgical procedures, because they demonstrate a much greater potential risk of blood-borne disease transmission during surgery than has been previously appreciated.

Magnifying chromoendoscopy: Effective diagnostic tool for screening colonoscopy

Magnifying chromoendoscopy: Effective diagnostic tool for screening colonoscopy

Identification of Epithelial Gaps in Human Small and Large Intestine by Confocal Endomicroscopy

Confocal endomicroscopy is an emerging technology that poses the endoscopist with challenges for identifying epithelial structures in the human intestine. We have shown previously that the murine intestinal epithelium is punctuated by gaps caused by cell shedding. The goals of this study were to determine if confocal endomicroscopy could resolve the presence of human epithelial gaps and whether a proinflammatory cytokine could increase cell shedding. Intestinal mucosa was imaged after staining with acriflavine. Confocal endomicroscopy of 17 patients yielded 6277 images from the human terminal ileum and rectum. Results were validated by parallel studies of anesthetized mice (wild-type and Math1(DeltaIntestine)) using rigid confocal probe microscopy, 2-photon/confocal microscopy, and scanning electron microscopy. Human terminal ileal and rectal epithelium revealed unstained areas with the diameter of an individual epithelial cell, with 2 distinct morphologies. One had a "target" appearance, shown by mouse studies to be goblet cells. The other morphology had no nucleus and was observed by rigid confocal probe microscopy and scanning electron microscopy in the villi of Math1(DeltaIntestine) mice, which lack goblet cells. In the mouse, tumor necrosis factor alpha (0.33 microg/g intraperitoneally) increases cell shedding by 27-fold and caused loss of barrier function across 20% of resultant gaps. Confocal endomicroscopy can distinguish between epithelial discontinuities (gaps) and goblet cells in human intestine. Results suggest that the sealing of epithelial gaps must be considered as a component of the intestinal barrier and has potential implications for intestinal barrier dysfunction in human disease.

The Role of Fluoroscopy in the Endoscopic Management of Luminal Gastrointestinal Disorders

Fluoroscopy has emerged as a key technology in modern interventional endoscopy. When combined with standard video endoscopy, it dramatically increases our ability to obtain a global overview of therapeutic procedures in real-time. Despite the importance of fluoroscopy, few gastroenterologists have received formal training in the operation of radiologic equipment or manipulation of fluoroscopic images. A good understanding of the basics of fluoroscope setup and operation is critical to safely performing such procedures as push enteroscopy, double balloon endoscopy, and enteral stent placement using fluoroscopic guidance. This manuscript will review the fundamentals of fluoroscopy hardware, steps to minimizing radiation exposure to patients and staff, and specific modifications to general fluoroscopic techniques in specific clinical applications.

Autofluorescence Endoscopy Improves Detection of Adenomas in Patients with Familial Colorectal Cancer: Preliminary Results of a Back-to-Back Colonoscopy Study

Background: Surveillance colonoscopy is advised in familial colorectal cancer (CRC) syndromes. Especially in hereditary non-polyposis colorectal carcinoma (HNPCC) small or flat neoplastic lesions are prone to progress rapidly into colorectal cancer. These lesions can easily be missed on standard flexible white-light endoscopy (WLE). Autofluorescence endoscopy (AFE) is capable of detecting adenomatous lesions that are not recognized using WLE. The aim of the present study was to compare the sensitivity of autofluorescence endoscopy and white light endoscopy in diagnosing colorectal neoplasia in patients belonging to HNPCC or familial CRC families. Methods: Thirty consecutive asymptomatic patients (mean age 52 years) belonging to HNPCC or familial CRC families (one 1 st degree relative with CRC < 50 years or two 1 st degree relatives with CRC at any age) were recruited for examination with both WLE and AFE. First, standard WLE was performed using a standard video endoscope (CF160, Olympus, Japan). Immediately after the WLE procedure a 2nd endoscopist, unaware of the results of the previous WLE, performed AFE with an autofluorescence endoscopy system (Onco-LIFE, Xillix, Canada). During both procedures all lesions were photographed and videotaped, and graded according to size, morphology, and location. All lesions were judged to be either non-dysplastic or suspicious using both techniques and were removed and collected during AFE. Lesions missed on second pass by AFE were identified and removed on 3rd pass by WLE. Sensitivity and specificity were calculated by correlating positive and negative findings to the pathology results. Results: A total of 31 adenomas were detected in 18 patients. Twelve patients had no abnormalities. White light endoscopy identified 16 adenomas in 9 patients. All these lesions except for one were also found by AFE. This method however identified an additional number of 15 adenomas in 13 patients, thereby significantly increasing the detection rate (p < 0.001). The 15 additionally detected lesions included 4 flat adenomas, 9 small adenomas with a mean size of 2.3 ± 0.7 mm (range 1-3 mm), and two sessile polyps (size 4 mm). The sensitivity of AFE for detecting adenomas was 97% and the specificity was 59%. For WLE the sensitivity and specificity for detecting adenomas was 52% and 71% respectively. Conclusion: Autofluorescence endoscopy significantly improves the detection of colorectal neoplasia in patients with HNPCC or familial colorectal cancer. For this specific population the additional value of autofluorescence endoscopy is mainly in the detection of small or flat lesions.