Gastrointestinal cancers represent the leading cause of cancer-related death worldwide. The diagnosis of precursor and early gastrointestinal cancers is therefore of great interest as their endoscopic and surgical treatment present the best chance for cure. These pre and early cancers are often subtle and can pose a challenge for gastroenterologists to diagnose using standard white light endoscopy. Image-enhanced endoscopy has been developed to improve visualization. The term image-enhanced endoscopy encompasses various means of enhancing contrast during endoscopy using dye, optical, and electronic methods. Image-enhanced endoscopy allows improved visualization of lesions and can be used to gain insight into the pathology of the lesion, which in turn may direct treatment decisions. The aim of this educational DVD is to summarize the techniques of image-enhanced endoscopy and to provide a guide for its current application as well as future potential in the field of endoscopy. Based on the literature and our experience, we will present image-enhanced endoscopy. We will first provide a comprehensive, illustrative description of the various techniques of image-enhanced endoscopy and their specific preparations, properties, and indications. Through specific case examples, we will show the components of its application. We will conclude with the current recommendations of image-enhanced endoscopy and its future potential. Proper image-enhanced endoscopy techniques include the adequate equipment and preparation as well as an understanding of the properties of each imaging modality and mucosal pathology. Combining high resolution or high definition with image-enhanced endoscopy techniques may improve the accuracy of endoscopic diagnoses and ultimately the application of therapy at the time of assessment rather than waiting for the pathologic evaluation in order to direct therapy. The most optimal way to view image-enhanced endoscopy is to use high resolution endoscopes. When available, high definition will provide more detail of the structures visualized. High definition systems are now available by all major manufacturers. Translucent distal attachment caps and spray catheters should be easily accessible in the endoscopy lab. Translucent distal attachments or cap devices may facilitate both diagnosis and treatment. They help to stabilize the scope position, maintain focus, and keep the lumen open. Distal spray or ball-tip catheters can be used to apply the stains evenly throughout the mucosa or intensely over a specific area of interest. These are especially needed in the application of Lugol's solution or crystal violet. The application of image-enhanced endoscopy requires readily available solutions. We will focus on the stains that are commonly used, described in the literature, and maintained in most pharmacies. Lugol's solution is an absorptive dye composed of a mixture of potassium iodide and iodine in water. Normal squamous epithelium binds iodine. The use of Lugol's solution has been shown to improve the endoscopic detection and delineate high-grade dysplasia and early squamous cell carcinoma of the esophagus in high-risk patient populations. The diluted solution is sprayed on the mucosa via a spray catheter and is absorbed by glycogen-containing cells to produce a dark, greenish-brown stain. Normal mucosa will stain intensely for about 5 to 8 minutes, whereas dysplastic and neoplastic areas will not. Lugol's solution preparation requires 5% solution, 2 20-mL vials of sterile water, and a spray catheter. 2% solution is prepared by mixing 8 mL of 5% solution with 12 mL of water, as shown here. Indica carmine is the most commonly used dye-based image-enhanced endoscopy technique. It is not absorbed, but extenuates the border and surface topography of a lesion by pooling into the crevices of the mucosal surface to outline subtle changes in elevation or depression. It has been shown most useful in the endoscopic diagnosis and treatment of non-polypoid columnar neoplasm. In Japan, where gastric cancer is common, diluted indica carmine solution is often sprayed through the entire stomach for re-examination after a standard white light examination. In the colon, diluted indica carmine is selectively sprayed onto areas of suspicious mucosa. 0.2% indica carmine solution is prepared by mixing 5 mL of 0.8% indica carmine with 15 mL of sterile water. The diluted solution is sprayed onto the area of interest using a syringe via the accessory channel of a standard endoscope. Crystal violet is a vital stain preferentially taken up by the colonic crypts. Following removal of surface mucus with vigorous washing, adequate staining with crystal violet is achieved with the application of a few drops using a non-traumatic spray catheter. The stain is absorbed by the mucosa around the pit openings to provide a vivid coloration of the pit margins. Crystal violet has been primarily used in pit pattern analysis of colorectal neoplasia. Methylene blue is taken up by actively absorbing intestinal epithelial cells. It does not stain non-absorptive gastric or squamous epithelia and has thus predominantly been applied to enhance the detection of metaplastic epithelium with absorptive properties such as the specialized columnar epithelium of Barrett's esophagus. A significant level of inter-observer variability on the use of methylene blue staining in the detection of Barrett's esophagus has notably been reported. 1-3% diluted acetic acid acts as a mucolytic. When sprayed onto the columnar epithelium, acetic acid penetrates into the cells, stroma, and vascular network. Within the cells, acetic acid alters the tertiary structure of the cellular proteins and leads to an increased opacity of the columnar epithelium as well as capillary congestion. This in turn enhances the mucosal contrast. Novel equipment-based endoscopic imaging technologies have been recently developed that use manipulations of the light source or captured light to enhance visualization of the surface. Narrowband imaging by Olympus, spectral estimation technology by Fujinon, and surface enhancement by Pentax have been described. With a switch of a button at the control body of the endoscope, the narrowband imaging is an optical technology designed to enhance contrast of the superficial layer of the mucosa. In normal endoscopic observation, standard white light composed of red, green, and blue light is used for illumination. Narrowband imaging, however, uses just two narrow bands of light produced by a filter built into the light source. The narrowband technology uses a light source centered at 415 nm, blue, and 540 nm, green, with a narrowed bandwidth of 30 nm. That cuts optically obstructive light and contributes to increased contrast. The narrowed light penetrates primarily the mucosa and submucosa and is absorbed primarily by hemoglobin. Thus, surface microvessels are visible as dark structures. Because the density and shape of microvessels change in neoplasia, the use of narrowband imaging has the potential to aid the endoscopist in a pathologic diagnosis. The spectral estimation technology uses computerized processing to convert standard RGB signals from the endoscope's CCD. The technology uses a 3x3 matrix to perform a linear mathematical transformation of the red, green, and blue lights into the system output. In practice, the system allows the user to select a combination of three wavelengths and the processor will then use the corresponding matrix to process the RGB signal. The combination of dye and equipment-based image-enhanced endoscopy is complementary in clinical practice. As illustrated in this case of squamous cell carcinoma of the esophagus, image-enhanced endoscopy aided in the appreciation of the pathology. The following video segment illustrates the clinical use of image-enhanced endoscopy during colonoscopy. This is a 65-year-old man who was referred to our unit for evaluation of a flat lesion in the rectum. And here we are using the high-definition Olympus endoscope with an NBI function. And here's the lesion being visualized as we come back into the distal rectum. Here the lesion appears to have the brainy salicyte pattern typical of tubular phallus adenoma. And here we are about to deploy the NBI function. So again, the surface pattern can be closely examined. With a close examination of the lesion, we can then decide that this lesion would be amenable to endoscopic therapy using EMR. The application of image-enhanced endoscopy may augment the diagnosis and therapy of gastrointestinal diseases. Pesh and colleagues recently reported that most Barrett's esophagus with high-grade dysplasia is a completely flat morphology, reflecting the difficulty in its detection. Careful inspection of the esophageal lumen should be standard practice during upper endoscopic evaluation due to the subtle appearance of esophageal lesions. Image-enhanced endoscopy has been applied towards identification of esophageal neoplasia in both squamous and Barrett's epithelium. Squamous cell high-grade dysplasia in early carcinoma can be nonpolypoid, being slightly elevated, flat, or depressed, and only recognized by its slight erythema. Careful inspection of the esophageal mucosa was performed in this high-risk patient with a history of heavy tobacco and alcohol use. There was an area of subtle erythema, raising suspicion for a malignant lesion. The use of Lugol's has been shown to improve the endoscopic detection of high-grade dysplasia and squamous cell cancer of the esophagus in patients at increased risk. As illustrated in this case, the application of Lugol's solution aided in the endoscopic diagnosis of dysplasia. The sharply demarcated, unstained epithelium delineates the dysplastic lesion from normal squamous epithelium. This is a crucial component in order to define the lesion borders and assess for the completeness of resection. Image-enhanced endoscopy enhances the visualization of the abnormal capillary vessels in high-grade dysplasia and cancers. The abnormal size, orientation, and number of surface capillaries with distinct borders are characteristics of squamous cell neoplasia. Surveillance endoscopy following the partial esophagectomy for an invasive squamous cell cancer showed the anastomotic scar with a focal area of erythema. Inspection with narrowband imaging and digital magnification highlighted the abnormal surface vascularity at the anastomosis, suggesting residual dysplasia. Image-enhanced endoscopy was used to target endoscopic resection. Pathology showed squamous high-grade dysplasia. This patient was referred for endoscopic resection of a squamous cell dysplastic nodule. Upon mucosal inspection, however, the lesion appeared circumferential. Narrowband imaging similarly showed a diffuse increase in surface vascularity. Lugol's solution was applied. There was circumferential absence of staining, further confirming the extent of dysplasia. The patient underwent surgical resection. Pathology showed multifocal high-grade dysplasia and invasive squamous cell cancer. Adenocarcinoma of the esophagus and the gastric cardia has increased dramatically. Prospective studies estimate the mean annual cancer incidence in patients with Barrett's esophagus to be about 1%. The issue of Barrett's surveillance, however, is complicated by imperfect diagnostic tests, given that up to 3 quarters of Barrett's high-grade dysplasia or early cancer are completely flat. And current therapies carry a high morbidity and mortality. Image-enhanced endoscopy may augment the identification of flat, inconspicuous, and patchy Barrett's dysplasia and facilitate targeted biopsy and therapy. Barrett's dysplasia can be inconspicuous. As image-enhanced endoscopy techniques continue to evolve, the current recommendation to pursue random biopsy sampling, according to the Seattle Protocol, is upheld. In this case, the patient was referred for endoscopic resection of high-grade dysplasia found on random biopsy during Barrett's dysplasia surveillance endoscopy. We meticulously inspected the long segment of Barrett's mucosa using image-enhanced endoscopy with high-definition and narrowband imaging. There were reddish areas of increased vascularity enhanced using narrowband imaging. No focal lesion was seen, however. Resection was performed and pathology showed intestinal metaplasia without dysplasia. Here, a slightly reddish small area is appreciated at the squamorculumnar junction with high-definition and digital magnification endoscopy. The application of indigo carmine differentiates the slightly raised surface. Pathology showed Barrett's dysophagus with high-grade dysplasia. This is an example of a larger lesion of Barrett's dysplasia. Attention should be paid to the reddish area between 3 and 7 o'clock. Using high-definition imaging with a translucent distal attachment device, there is clear visualization of the redness of the lesion. Narrowband imaging further differentiates the vascularity of the lesion. An indigocarmine application enhanced the slightly raised topography of the lesion within the Barrett's epithelium. There are times when image-enhanced endoscopy aids in the differentiation of early from invasive cancer, as in this case of an ulcerated lesion diagnosed as advanced adenocarcinoma of the esophagus. Initially, it was challenging to identify the short-segment Barrett's with high-grade dysplasia due to its location at the GE junction. A distal attachment translucent cap facilitated stable scope positioning to accurately mark the periphery and proceed with endoscopic submucosal dissection using the IT knife. There is sufficient data to support the use of image-enhanced endoscopy in the detection of early squamous cell carcinoma of the esophagus. The use of image-enhanced endoscopy in the diagnosis and therapy of Barrett's esophagus with dysplasia and early cancer is currently under study. Image-enhanced endoscopy using diluted indigo carmine solution is routine in the diagnosis and treatment of early gastric cancer. We direct you to view the ASGE educational program, Diagnosis and Treatment of Early Gastric Cancer, for detailed instruction on the application of indigo carmine throughout the stomach during gastric cancer screening endoscopy. In the following cases, we will outline the important role that image-enhanced endoscopy plays in the diagnosis and therapy of early gastric cancer. During routine upper endoscopy, reddish-appearing, irregular mucosa was seen on the anterior wall of the greater curvature using high-definition imaging in a standardized fashion. Following lesion identification, both high-definition and indigo carmine are used to assess its surface topography and the lesion's depth of invasion. The mucosa is carefully scrutinized to delineate the lesion border from surrounding normal mucosa. The lesion is then marked. Circumferential incision is performed, followed by submucosal dissection. Lastly, the specimen is oriented on wood for precise pathologic assessment. Indigo carmine also serves as a therapeutic aid in early gastric cancer. As shown here, after marking and circumferential incision, the submucosa is injected with a mixture of indigo carmine and saline. The insulated tip knife is used to dissect the submucosa. Care is taken to only dissect the blue colored tissue, as only the submucosa would contain the blue indigo carmine solution. Other methods, such as optical or electronic image-enhanced endoscopy, are not routinely used. However, we have found these equipment-based image endoscopy techniques helpful in select cases. For example, this cardiac lesion was evaluated using spectral estimation technology in the 10 different modes to gain further detail of the surface pattern and its borders, given its challenging location. The border of the lesion was marked, and endoscopic submucosal dissection was performed for unblocked pathologic specimen. Pathology showed intramucosal adenocarcinoma. This patient was referred following repeated biopsy that showed high-grade dysplasia with no clearly defined lesion. Using high definition, there was slightly raised retus mucosa in the proximal body. The lesion was best appreciated in retroflexed view. A pre-pyloric gastric ulcer is... The application of optical or electronic equipment-based image-enhanced endoscopy in the stomach is currently under study. Image-enhanced endoscopy is not routinely used in the management of diseases of the small intestine, although various duodenal abnormalities including inflammatory folds, villus atrophy, adenoma, and lymphoma have been evaluated using these techniques. Subtle mucosal changes seen on standard endoscopy are more visible with image-enhanced endoscopy. Herein, we will present such cases to demonstrate the adjunctive role of image-enhanced endoscopy in the diagnosis of duodenal pathology. We will also highlight the value of a translucent distal attachment device in the duodenum. The cap is useful to stabilize the endoscope position, examine the junction between the bulb and the descending duodenum, and to closely and steadily examine the mucosa, as demonstrated in this evaluation of a duodenal adenoma. This patient was referred to evaluate a mass in the second portion of the duodenum that was identified on abdominal CT in the setting of severe pancreatitis. An upper endoscopy performed using a high-definition endoscope equipped with a cap showed slightly erythematous and hemorrhagic mucosa. The villi were elongated but did not appear adenomatous. Further comparison of the edematous mucosa to the surrounding mucosa using narrowband imaging showed no significant pattern difference. The carmine spray provided further suggestion of inflammatory folds. Endoscopic ultrasound showed redundant folds with no mass and biopsy confirmed inflammatory mucosa. An endoscopic ultrasound was requested to evaluate for chronic pancreatitis as a cause of weight loss in this patient with a history of heavy alcohol use. The examination was begun using a high-definition endoscope. Upon entering the duodenum, there was a scalloping of the folds extending from the bulb to the second portion. The mucosa appeared flat with absence of villi. The villisatrophy could be better appreciated using narrowband imaging and indigo carmine spray. Even when the lumen was immersed in water, villi could not be seen. Biopsy proved villis blunting, mucosal flattening, and severe inflammation, confirming the diagnosis of celiac sprue. This patient had an upper endoscopy for dyspepsia. Upon entering the second portion of the duodenum, a sessile lesion was seen. The mucosal pattern was consistent with an adenoma. Regularity of the adenomatous mucosa was observed under high-definition white light, narrowband imaging, and indigo carmine. The delineation of adenoma from normal mucosa is clearly demonstrated here. This lesion was later removed using endoscopic mucosal resection technique and proved to be an adenoma. In this case, a patient was referred for endoscopic resection following a biopsy that showed duodenal adenoma. The lesion was studied in detail prior to mucosal resection using a high-definition endoscope with a translucent cap. It appeared circumferential, and the borders were difficult to define. The cap provided the stability to allow fine movements to determine the border at the junction of the distal bulb and descending duodenum with sparing of the ampulla. Careful examination of the mucosa showed a regular adenomatous pattern, and endoscopic ultrasound confirmed only mucosal involvement without evidence of invasive cancer. As such, in lieu of a Whipple procedure, the patient had a pyloric sparing partial duodenal resection. The pathology showed duodenal adenoma with high-grade dysplasia. This is a case of a duodenal lymphoma. The narrow band imaging provides sharp contrast of the lymphatics within the lesion. Currently, studies on the use of image-enhanced endoscopy of the small intestine are underway. Our cases have illustrated its potential in the evaluation of duodenal pathology. Image-enhanced endoscopy in the colon is most useful in the evaluation of areas suspicious to contain non-polypoid colorectal neoplasms, and is helpful in delineating the lesion borders and assessing the lesion margins post-resection. Exploratory studies on the differentiation of non-neoplastic and neoplastic polyps have been performed. Image-enhanced endoscopy, however, is not a necessity in the diagnosis and interpretation of all colorectal lesions. In this case of standard-definition endoscopy, the benign-appearing villus adenoma can be clearly appreciated. Similarly, melanosis coli is a striking image in standard-definition alone. There are times, nonetheless, when image-enhanced endoscopy can be informative in the differentiation of normal from colorectal pathology. In this case, a possible lesion was seen at the appendiceal orifice. The orifice and surrounding mucosa were inspected using narrowband imaging. Cold surface analysis showed a normal mucosa pattern. Here, attention was drawn to the sigmoid prominence during colorectal cancer screening examination. The mucosal pattern was scrutinized using high-definition zoom and narrowband imaging for the diagnosis of an inverted direticulum. The prolapsed tissue seen here was initially concerning for neoplasia. However, close evaluation of the mucosa showed a normal appearance, suggestive more of a benign inflammatory fold. The following cases will illustrate the standard mucosal patterns of colorectal lesions as seen using image-enhanced endoscopy techniques. The indigo carmine solution pulls into the mucosal pits of the lesion, whereas narrowband imaging enhances surface microvasculature. Familiarity and recognition of the colorectal lesion patterns facilitates histopathologic diagnosis and helps to direct immediate treatment decisions. Anomenic grooves are the normal morphology in colonic mucosa. They can be better observed after spraying dye, such as indigo carmine. Hyperplastic lesions show a characteristic asteroid pit that is enhanced with indigo carmine. They are essentially absent of microvascularity. The hyperplastic mucosal pattern is further shown in the following videos. The paleness of this hyperplastic lesion seen on NBI further reflects the absence of vascularity in such lesions. The indigo carmine spray enhances the characteristic asteroid pit of hyperplastic lesions. In another case, the characteristic asteroid pit of a hyperplastic lesion can be seen using white light alone. The use of narrowband imaging further delineates the mucosal pit pattern. Serrated adenoma is a relatively newly defined entity of colorectal neoplasm first reported in 1990. The mucosal pit pattern of serrated adenoma shows a combination of hyperplastic and adenomatous features. The mucosal pattern, however, of serrated adenoma is currently under study. In adenomatous lesions, the pits appear round or tubular. The large tubular pits resemble the sulci of the brain. Indigo carmine pools into the crevices to enhance the contrast. Using narrowband imaging, the clear pit pattern is observed by the nest of the microvessels around the pits. Here, using standard definition, the borders of this flat adenoma are difficult to appreciate prior to the use of narrowband imaging. prior to the use of narrowband imaging. A similar case using high definition is better appreciated using narrowband imaging. The surface topography of the settled depressed lesion overlying a fold is further enhanced using narrowband imaging and indigo carmine. The borders of this flat rectal adenoma were best delineated using image enhanced endoscopy in order to distinguish the adenomatous mucosa from normal. The lesion was resected using mucosectomy and the pathology confirmed adenoma. The extent of this adenoma masquerading as a thickened fold is only appreciated following the application of indigo carmine. A full hemicircumferential flat lesion is seen here crossing several folds. Narrowband imaging helps to delineate its borders. The mucosal pits of carcinoma show an irregular arrangement and vary in size. The microvessels show irregular reticular pattern with heterogeneity in vessel thickness and distribution. In cases of invasive carcinoma there is even a loss of pits resulting in an amorphous structure and avascularity. Image enhanced endoscopy with indigo carmine is commonly used to assess the lesion morphology and border to precisely direct endoscopic mucosal resection therapy. In this case a subtle area of redness is seen upon withdrawal using standard definition imaging. Indigo carmine was sprayed to closer inspect the mucosal surface pattern and delineate the non-polyploid lesion border. Submucosal saline was injected followed by mucosectomy. Immediately following mucosectomy it is suggested to analyze the pit pattern of the tissue at the resection margin. Outcomes analysis of EMR of flat lesions more than 2 centimeters showed a reduction of local neoplastic recurrence from 9% to less than 1% following the implementation of the routine use of image enhanced endoscopy. Image enhanced endoscopy was used to diagnose and treat this sequel adenoma. Immediately following mucosectomy it is suggested to analyze the pit pattern of the tissue at the resection margins with image enhanced endoscopy either dye based or electronic based techniques to assure completeness of resection. These techniques are also useful in the assessment of the scar site for local recurrence following endoscopic resection therapy. Here the mucosa at the scarred resection site showed no evidence of adenomatous tissue. Image enhanced endoscopy is most useful in the evaluation of areas suspected of containing nonpolypoid colorectal neoplasms and in classifying and defining the borders of the lesions. Standard white light endoscopy is routinely used. Image-enhanced endoscopy has been applied as an adjunctive endoscopic diagnostic and treatment tool in specialized academic centers but is otherwise not currently in widespread use. Potential barriers to the dissemination of image-enhanced endoscopy include perceptions of its inefficiency and exuberant cost, inadequate mechanism for reimbursement, lack of standardized training and techniques, and deficiency of high-quality comparison studies. Current methods of image-enhanced endoscopy is most useful for the evaluation of mucosal pathology. For example, neoplasms covered by normal mucosa may be misinterpreted in a case of submucosal pathology. Image-enhanced endoscopy techniques are currently under study. As endoscopists try to gain an understanding of the subtle malignant patterns. For example, in this case, the Barrett's nodule appears highly suspicious for high-grade dysplasia with its redness and nodularity. However, there is no definitive malignant pattern identified using image-enhanced endoscopy. Similarly, this poorly differentiated adenocarcinoma is covered by squamous mucosa. An adenomatous mucosal pattern seen here using narrowband imaging covered the appendiceal orifice. Using submucosal saline injection, endoscopic mucosal resection. Inspection for completeness of resection following EMR was challenging in this case due to the appendiceal anatomy. Our assessment was still limited despite the use of image-enhanced endoscopy techniques, and the patient was referred for surgical evaluation. In the following segment, we will share with you some of the potential future applications of image-enhanced endoscopy. Genetic findings of pre- and early cancers of the oro- and hypo-pharynx are similar to squamous cell carcinoma of the esophagus. On white light endoscopy, these lesions are typically slightly more reddish than the surrounding mucosa and are difficult to diagnose. Muto and colleagues used optical image-enhanced endoscopy to describe early oropharyngeal and hypopharyngeal squamous cell carcinoma. He described them to have distinct microvascular patterns appreciable as a brown area using narrow band imaging such as in the lesion seen here. This patient had a squamous cell cancer of the palate resected months earlier. The irregular vascular pattern surrounding the prior resection site was suspicious for local recurrence. Surgical inspection of the esophagus, oro-pharynx, and nasopharynx showed no metacronous lesion. Image-enhanced endoscopy may provide an opportunity to assess disease activity of ulcerative colitis of the entire colorectal mucosa rather than simply from a random and limited tissue sample. With indigo carmine and high magnification, fine mucosal morphologic features can be visualized and interpreted. A number of studies have suggested that inflamed mucosa can be assessed with image-enhanced endoscopy using high magnification colonoscopy. With this, fine mucosal morphologic features such as larger crypt openings, mucosal defects, yellowish-whitish patches, villus-like and nodular mucosa can be visualized and interpreted. These changes have been correlated to be an independent risk factor for relapse during medical therapy. Colitis-associated neoplasms can be difficult to detect, as the growth pattern of colitic dysplastic tissue is often multifocal and flat. Image-enhanced endoscopy may potentially facilitate earlier detection of colitis-associated dysplasia as it may unveil subtle lesions and provide a more targeted approach to surveillance. In a randomized controlled trial, Kieslidge and colleagues evaluated the use of dilute methylene blue solution sprayed throughout the colon at 30-centimeter segment intervals during surveillance colonoscopy in ulcerative colitis patients. Significantly more intraepithelial neoplasia was detected in the group that received methylene blue. Recent reports on the use of optical or electronic image-enhanced endoscopy techniques have also shown promise in this patient population. The application of crystal violet in this patient with ulcerative colitis showed a mucosal pattern consistent with invasive carcinoma. Exploration of the utility of specialized image-enhanced techniques to facilitate the detection and interpretation of submucosal pathology is of interest. During this routine upper endoscopy, multifocal carcinoid lesions appeared more prominent with a yellow hue using the spectral estimation technology. The recent introduction of optical and electronic methods may expand the clinical adaptation of image-enhanced endoscopy and encourage further research of the efficacy, reliability, and cost-effectiveness of this technique in diagnostic and interventional gastrointestinal endoscopy. There is sufficient data to support the use of image-enhanced endoscopy in the detection of early squamous cell carcinoma of the esophagus and in the management of early gastric cancer and superficial colorectal lesions.

image-enhanced endoscopy

gastrointestinal cancers

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visualization techniques

dyes

equipment-based technologies

future applications