title: A smart atlas for endomicroscopy using automated video retrieval.
abstract: To support the challenging task of early epithelial cancer diagnosis from in vivo endomicroscopy, we propose a content-based video retrieval method that uses an expert-annotated database. Motivated by the recent successes of non-medical content-based image retrieval, we first adjust the standard Bag-of-Visual-Words method to handle single endomicroscopic images. A local dense multi-scale description is proposed to keep the proper level of invariance, in our case to translations, in-plane rotations and affine transformations of the intensities. Since single images may have an insufficient field-of-view to make a robust diagnosis, we introduce a video-mosaicing technique that provides large field-of-view mosaic images. To remove outliers, retrieval is followed by a geometrical approach that captures a statistical description of the spatial relationships between the local features. Building on image retrieval, we then focus on efficient video retrieval. Our approach avoids the time-consuming parts of the video-mosaicing by relying on coarse registration results only to account for spatial overlap between images taken at different times. To evaluate the retrieval, we perform a simple nearest neighbors classification with leave-one-patient-out cross-validation. From the results of binary and multi-class classification, we show that our approach outperforms, with statistical significance, several state-of-the art methods. We obtain a binary classification accuracy of 94.2%, which is quite close to clinical expectations.
authors.affiliation: INRIA Sophia Antipolis, Asclepios Research Project, 2004 route des Lucioles - BP 93, 06902 Sophia Antipolis Cedex, France. barbara.andre@sophia.inria.fr
authors.forename: Barbara
authors.initials: B
authors.lastname: André
authors.forename: Tom
authors.initials: T
authors.lastname: Vercauteren
authors.forename: Anna M
authors.initials: AM
authors.lastname: Buchner
authors.forename: Michael B
authors.initials: MB
authors.lastname: Wallace
authors.forename: Nicholas
authors.initials: N
authors.lastname: Ayache
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D003111:Colonic Polyps / Q000473:pathology*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018715:Microscopy, Video / Q000379:methods*; D008953:Models, Anatomic; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique