Toyoki Kudo

Efficiency of endocytoscopy in differentiating types of serrated polyps

BACKGROUND Accurate endoscopic criteria are needed to differentiate serrated polyps, including hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA), because some are precursors of colorectal cancers. OBJECTIVE To determine the endocytoscopic features of each type of serrated polyp, especially the shapes of lumens and nuclei. DESIGN Retrospective study. SETTING Single, tertiary-care referral center. PATIENTS Patients who underwent removal of serrated polyps from May 2005 to December 2012. INTERVENTION Endocytoscopy was performed. Endocytoscopic images were evaluated by assessing the shapes of the lumens and nuclei of the target lesions. MAIN OUTCOME MEASUREMENTS The significant endocytoscopic features in differentiating among types of serrated polyps. RESULTS Of the 58 eligible lesions, 27 were classified as HP, 12 as SSA/P, and 19 as TSA. Most HPs (77.8%) had star-like lumens, and most SSA/Ps (83.3%) had oval lumens. The lumens of TSAs were serrated (31.6%) or villous (68.4%), with both shapes seen only in TSAs. Most HPs (92.6%) and SSA/Ps (75.0%) had small, round nuclei, and all TSAs had fusiform nuclei. Features significantly differentiating TSAs from HPs and SSA/Ps were the presence of fusiform nuclei (P < .001) and villous (P < .001) and serrated (P = .002) lumens. The presence of oval lumens was significantly characteristic of SSA/Ps (P < .001), and the presence of star-like lumens was significantly characteristic of HPs (P < .001). LIMITATIONS Retrospective design. Single-center study. CONCLUSION The shape of lumens and nuclei on endocytoscopy can efficiently differentiate among the different types of serrated polyps. ( CLINICAL TRIAL REGISTRATION NUMBER UMIN Clinical Trials Registry UMIN000007850.).

Characterization of Colorectal Lesions Using a Computer-Aided Diagnostic System for Narrow-Band Imaging Endocytoscopy

Figure 1. Output image. (1) Computer diagnosis. (2) Input endocytoscopy with narrow band imaging. (3) Extracted vessel image, in which the green area denotes the extracted vessels. The light-green vessel has the maximum diameter. (4) Probability of computer diagnosis. 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 REndoscopy established the Preservation and Incorporation of Valuable Endoscopic Innovations for diminutive colorectal polyps. Preservation and Incorporation of Valuable Endoscopic Innovations suggests that, if an endoscopist diagnoses an agreement of >90% in determining postpolypectomy surveillance intervals and a negative predictive value of >90% with adenomatous histology, pathologic diagnosis might not be necessary. Although magnifying chromoendoscopy, narrow-band imaging (NBI), endocytoscopy (EC), and confocal laser endomicroscopy are highly accurate, interpretation of these modalities is difficult for novices. Furthermore, achieving a negative predictive value of >90% for adenoma is not easy using these modalities and requires comprehensive experiments. To achieve a breakthrough on this issue, we developed a computer-aided diagnosis (CAD) system for EC. This system automatically provides highly accurate diagnosis as expert endoscopists concurrently take EC images (Video Clip 1). Our previous system, based on glandular structural and cellular atypia, required endoscopists to use dye for staining. In contrast, the endocytoscopic vascular pattern can effectively evaluate microvessel findings using EC with NBI (EC-NBI) without using any dye. We reported that EC-NBI has a highly accurate diagnostic ability, similar to other modalities. Because dye staining complicates the procedure, our CAD system for EC-NBI represents a powerful tool for novices and experts who do not use dyes on a routine basis. Therefore, we developed a tentative CAD system model for EC-NBI image. Abbreviations used in this paper: CAD, computer-aided diagnosis; EC, endocytoscopy; EC-NBI, endocytoscopy with narrow-band imaging; NBI, narrow-band imaging; SSA/P, sessile serrated adenoma/polyp.

Management of T1 colorectal cancers after endoscopic treatment based on the risk stratification of lymph node metastasis.

Recent advances in endoscopic technology have allowed many T1 colorectal carcinomas to be resected endoscopically with negative margins. However, the criteria for curative endoscopic resection remain unclear. We aimed to identify risk factors for nodal metastasis in T1 carcinoma patients and hence establish the indication for additional surgery with lymph node dissection.

Endocytoscopy can provide additional diagnostic ability to magnifying chromoendoscopy for colorectal neoplasms

Pit pattern (PIT) diagnosis with magnifying chromoendoscopy is effective diagnostic method for predicting a massively invasive submucosal colorectal cancer (SMm) which has possibility of metastasis, whereas endocytoscopy (EC) is recently reported to provide excellent diagnostic ability by enabling in vivo cellular visualization. The aim was to assess the additional diagnostic value of EC to PIT for diagnosing colorectal lesions.

Double staining with crystal violet and methylene blue is appropriate for colonic endocytoscopy: An in vivo prospective pilot study

Endocytoscopy (EC) at ultra‐high magnification enables in vivo visualization of cellular atypia of gastrointestinal mucosae. Clear images are essential for precise diagnosis by EC. The aim of the present study was to evaluate the optimal staining method for EC in the colon.

Endocytoscopic narrow-band imaging efficiency for evaluation of inflammatory activity in ulcerative colitis.

AIM To assess the efficacy of endocytoscopic narrow-band imaging (EC-NBI) for evaluating the severity of inflammation in ulcerative colitis (UC). METHODS This retrospective study was conducted at a single tertiary care referral center. We included UC patients who underwent colonoscopy with endocytoscopy from July 2010 to December 2013. EC-NBI was performed, and the images were evaluated by assessing visibility, increased vascularization, and the increased calibers of capillaries and were classified as Obscure, Visible or Dilated. Obscure was indicative of inactive disease, while Visible and Dilated were indicative of acute inflammation. This study received Institutional Review Board approval. The primary outcome measures included the diagnostic ability of EC-NBI to distinguish between active and inactive UC on the basis of histological activity. The conventional endoscopic images were classified according to the Mayo endoscopic score. A score of 0 or 1 indicated inactive disease, whereas a score of 2 indicated active disease. RESULTS Fifty-two patients were enrolled. There was a strong correlation between the EC-NBI findings and the histological assessment (r=0.871, P<0.01). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EC-NBI for diagnosing acute inflammation were 84.0%, 100%, 87.1%, 100%, and 92.3%, respectively, while those for the Mayo endoscopic score were 100%, 40.7%, 100%, 61.0%, and 69.2%, respectively. Compared with conventional endoscopy, EC-NBI was superior in diagnostic specificity, negative predictive value, and accuracy (P<0.001, P=0.001 and P=0.047, respectively). CONCLUSION The EC-NBI finding of capillaries in the rectal mucosa was strongly correlated with histological inflammation and aided in the differential diagnosis between active and inactive UC.

Accuracy of computer-aided diagnosis based on narrow-band imaging endocytoscopy for diagnosing colorectal lesions: comparison with experts

PurposeReal-time characterization of colorectal lesions during colonoscopy is important for reducing medical costs, given that the need for a pathological diagnosis can be omitted if the accuracy of the diagnostic modality is sufficiently high. However, it is sometimes difficult for community-based gastroenterologists to achieve the required level of diagnostic accuracy. In this regard, we developed a computer-aided diagnosis (CAD) system based on endocytoscopy (EC) to evaluate cellular, glandular, and vessel structure atypia in vivo. The purpose of this study was to compare the diagnostic ability and efficacy of this CAD system with the performances of human expert and trainee endoscopists.MethodsWe developed a CAD system based on EC with narrow-band imaging that allowed microvascular evaluation without dye (ECV-CAD). The CAD algorithm was programmed based on texture analysis and provided a two-class diagnosis of neoplastic or non-neoplastic, with probabilities. We validated the diagnostic ability of the ECV-CAD system using 173 randomly selected EC images (49 non-neoplasms, 124 neoplasms). The images were evaluated by the CAD and by four expert endoscopists and three trainees. The diagnostic accuracies for distinguishing between neoplasms and non-neoplasms were calculated.ResultsECV-CAD had higher overall diagnostic accuracy than trainees (87.8 vs 63.4%;

Accuracy of diagnosing invasive colorectal cancer using computer-aided endocytoscopy

P=0.01