Proximity-aware interactive displays for rehabilitation centres

Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

Automatic View-Point Selection for Inter-Operative Endoscopic Surveillance

International audienceAbstract. Esophageal adenocarcinoma arises from Barrett’s esophagus, which is the most serious complication of gastroesophageal reflux disease. Strategies for screening involve periodic surveillance and tissue biopsies. A major challenge in such regular examinations is to record and track the disease evolution and re-localization of biopsied sites to provide targeted treatments. In this paper, we extend our original inter-operativerelocalization framework to provide a constrained image based search for obtaining the best view-point match to the live view. Within this context we investigate the effect of, (a) the choice of feature descriptors and color-space, (b) filtering of uninformative frames, (c) endoscopic modality, for view-point localization. Our experiments indicate an improvement in the best view-point retrieval rate to [92%, 87%] from [73%, 76%] (in our previous approach) for NBI and WL

Development Of A Prototype Of Video Synchronisation For Relocalization Of Biopsy Sites During Endoscopic Evaluation Of Barrett's Oesophagus: Preliminary Experimental And Clinical Study

International audienceINTRODUCTION: The prevalence of Barrett's oesophagus (BE) is 5 to 6% in the general population, with a progression from dysplasia to adenocarcinoma 0.6 to 0.7 patient-years. Hence, endoscopic surveillance is justified to detect early lesions accessible to endoscopic treatment. However, the relocalisation of lesions detected by biopsies may be difficult during follow-up endoscopies. The purpose of this study was to evaluate the prototype of a magnetic probe for accurate location of the position of the endoscope, allowing the relocalisation of this position in a subsequent endoscopy. We report the results of a feasibility study in pigs and the use of this device in two patients with BE. AIMS & METHODS: The system consists of an electromagnetic (EM) field transmitter and an EM probe constituting the electromagnetic tracking system (EMS) (NDI, Aurora). The EM probe is inserted through the operating channel of a double channel gastroscope. The EM field generator is positionned on the patient chest wall. The system also includes a new software developed at IHU/IRCAD, which performs simultaneous recording of the video from the endoscope alongwith its corresponding position, as measured by the EMS. During a second endoscopy, this software allows automatic synchronization of the recorded video to provide relocalisation of the endoscope in front of previous biopsy sites in the oesophagus. The system was tested in 5 anesthetized pigs. During the first endoscopy, ten markings were performed by argon plasma electrocoagulation (ERBE Tübingen, Germany) in the distal esophagus. The position of each marking was recorded by the system. A second operator to then performed a blind endoscopy on the same pigs and was asked to follow the system implicitly as a guide to relocate the markings. In 2 patients with BE, the system was then tested to facilitate relocalization of the biopsy sites. RESULTS: Ten markings were made in the distal oeosphagus of 5. After withdrawal of the endoscope the second operator found 48 of the 50 markings (96%) using the guidance provided by the system. The positioning of the endoscope provided by the EMS system was within a 2mm range from the initial positionning. In the evaluation of BE patients, the system relocalized the biospy sites within a range of 3mm. CONCLUSION: This preliminary study shows the feasibility of the EMS prototype to relocalize the endoscope in the oesophagus within an acceptable range. The clinical usefulness of this system should be evaluated further during the follow-up of patients with BE

Video Synchronization: An Approach to Biopsy Site Re-localization

International audienceBarrett’s esophagus (Barrett’s esophagus) is the pre-malignant lesion for the majority of patients with esophageal adenocarcinoma. The sequence of events from Barrett’s esophagus to adenocarcinoma has several steps, encompassing low grade intra-epithelial Neoplasia (LGIN), and high grade intra-epithelial neoplasia (HGIN). As it seems that this evolution spans many years, endoscopic surveillance for patients with Barrett’s esophagus has been advocated, to detect neoplasia at early and curable stages. In recent years endoscopic imaging techniques have improved greatly. However, even using sophisticated imaging techniques, the standard approach of comprehensive endoscopic biopsy protocol includes direct sampling from suspicious areas in combination with systematic random four quadrant biopsies (4QBs) every 1±2 cm along the length of the Barrett’s segment, according to the Seattle protocol, is recommended as the gold standard for surveillance. The approach is labor-intensive but iscurrently considered to be the state of the art. However, the primary problem is the inter-operative re-localization of these biopsy sites to guide the treatment. Often re-localization is performed using the markings made on the endoscope which are highly unreliable and prevent targeted treatments

Inter-Operative Biopsy Site Relocalization in Endoluminal Surgery

International audienceBarrett's oesophagus, a pre-malignant condition of the oesophagus has been on a rise in the recent years. The standard diagnostic protocol for Barrett's involves obtaining biopsies at suspicious regions along the oesophagus. The localization and tracking of these biopsy sites " inter-operatively " poses a significant challenge for providing targeted treatments and tracking disease progression. This paper proposes an approach to provide guided navigation and relocalization of the biopsy sites using an electromagnetic tracking system. The characteristic of our approach over existing ones is the integration of an EM sensor at the flexible endoscope tip, so that the endoscopic camera depth inside the oesophagus can be computed in real-time, allowing to retrieve and display an image from a previous exploration at the same depth. We firstly describe our system setup and methodology for inter-operative registration. We then propose three incremental experiments of our approach. First, on synthetic data with realistic noise model to analyze the error bounds of our system. The second on in-vivo pig data using an optical tracking system to provide a pseudo ground-truth. Accuracy results obtained were consistent with the synthetic experiments despite uncertainty introduced due to breathing motion, and remain inside acceptable error margin according to medical experts. Finally, a third experiment designed using data from pigs to simulate a real task of biopsy site relocalization, and evaluated by 10 GI experts. It clearly demonstrated the benefit of our system towards assisted guidance by improving the biopsy site retrieval rate from 47.5% to 94%

Clinical Evaluation of a Respiratory Gated Guidance System for Liver Punctures

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An Accuracy Certified Augmented Reality System for Therapy Guidance

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An Augmented Reality System to Guide Liver Punctures

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Vision augmentée de structures anatomiques abdominales recalées par stéréoscopie

National audienceno abstrac