Estimation de l'échelle des néoplasies en coloscopie par détection de la profondeur de défocalisation

National audienceLa coloscopie est l'examen médical privilégié dans le cadre du diagnostic et du traitement des maladies colorectales. Cette technique qualifiée de peu invasive permet aux gastro-entérologues d'explorer la cavité du côlon et d'ôter les néoplasies - proliférations cellulaires - telles que les polypes qui peuvent évoluer en tumeurs malignes. La taille, la texture ainsi que la forme des néoplasies constituent des critères essentiels à leurs diagnostics. L'estimation de la taille est cependant difficile à réaliser de part la perte de l'information de profondeur de la scène imagée par le gastro-entérologue. Nous proposons une amélioration de notre technique de détection de la Profondeur de Défocalisation (PD) permet- tant l'estimation de l'échelle des scènes endoscopiques par extraction de la PD au sein d'une séquence vidéo. L'estimation conjointe du suivi affine de la néoplasie au cours de la séquence vidéo et du flou de mise au point permet d'inférer avec une meilleure précision la taille des néoplasies. Par ailleurs, la méthode proposée est mieux adaptée aux conditions réelles de coloscopie pour lesquelles la manipulation du gastroscope peut être délicate

Estimation de l'échelle en coloscopie monoculaire par quantification du flou optique : étude de faisabilité

Session "Articles"National audienceLa coloscopie est aujourd'hui la procédure médicale privilégiée dans le cadre du diagnostic et du traitement des pathologies en gastroentérologie. Ce mode opératoire qualifié de "mini-invasif" repose sur l'utilisation d'un instrument optique flexible, le flexoscope, qui est introduit par voie basse dans le corps du patient pour permettre l'exploration du côlon. L'intervention est réalisée par un gastroentérologue qui s'appuie sur les images diffusées sur un moniteur afin d'établir un diagnostic et éventuellement procéder à la résection d'excroissances tumorales (néoplasies) si celles ci s'avèrent malignes. La taille de ces excroissances constitue une information essentielle a leurs diagnostics mais elles s'avèrent difficile à estimer pour le praticien qui ne dispose pas de l'information d'échelle de l'organe exploré. Les paramètres du système optique monofocale des flexoscope sont fixes et l'équipement est difficilement modifiable pour envisager l'intégration de méthodes actives de mesures. Cette étude de faisabilité propose une procédure permettant l'estimation de l'échelle des scènes coloscopiques basée sur l'estimation de la fonction de transfert du système optique du flexoscope par quantification du flo

Artificial intelligence and automation in endoscopy and surgery

Modern endoscopy relies on digital technology, from high-resolution imaging sensors and displays to electronics connecting configurable illumination and actuation systems for robotic articulation. In addition to enabling more effective diagnostic and therapeutic interventions, the digitization of the procedural toolset enables video data capture of the internal human anatomy at unprecedented levels. Interventional video data encapsulate functional and structural information about a patient's anatomy as well as events, activity and action logs about the surgical process. This detailed but difficult-to-interpret record from endoscopic procedures can be linked to preoperative and postoperative records or patient imaging information. Rapid advances in artificial intelligence, especially in supervised deep learning, can utilize data from endoscopic procedures to develop systems for assisting procedures leading to computer-assisted interventions that can enable better navigation during procedures, automation of image interpretation and robotically assisted tool manipulation. In this Perspective, we summarize state-of-the-art artificial intelligence for computer-assisted interventions in gastroenterology and surgery

Medical-grade Sterilizable Target for Fluid-immersed Fetoscope Optical Distortion Calibration

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal Therapy and Surgery) project. One of the aims of this project is to engineer novel, real-time image processing methods for intra-operative use in the treatment of congenital birth defects, such as spina bifida and the twin-to-twin transfusion syndrome. The developed target allows for the sterility-preserving optical distortion calibration of endoscopes within a few minutes. Good optical distortion calibration and compensation are important for mitigating undesirable effects like radial distortions, which not only hamper accurate imaging using existing endoscopic technology during fetal surgery, but also make acquired images less suitable for potentially very useful image computing applications, like real-time mosaicing. In this paper proposes a novel fabrication method to create an affordable, sterilizable calibration target suitable for use in a clinical setup. This method involves etching a calibration pattern by laser cutting a sandblasted stainless steel sheet. This target was validated using the camera calibration module provided by OpenCV, a state-of-the-art software library popular in the computer vision community.status: publishe

Medical-grade sterilizable target for fluid-immersed fetoscope optical distortion calibration

We have developed a calibration target for use with fluid-immersed endoscopes within the context of the GIFT-Surg (Guided Instrumentation for Fetal Therapy and Surgery) project. One of the aims of this project is to engineer novel, real-time image processing methods for intra-operative use in the treatment of congenital birth defects, such as spina bifida and the twin-to-twin transfusion syndrome. The developed target allows for the sterility-preserving optical distortion calibration of endoscopes within a few minutes. Good optical distortion calibration and compensation are important for mitigating undesirable effects like radial distortions, which not only hamper accurate imaging using existing endoscopic technology during fetal surgery, but also make acquired images less suitable for potentially very useful image computing applications, like real-time mosaicing. In this paper proposes a novel fabrication method to create an affordable, sterilizable calibration target suitable for use in a clinical setup. This method involves etching a calibration pattern by laser cutting a sandblasted stainless steel sheet. This target was validated using the camera calibration module provided by OpenCV, a state-of-the-art software library popular in the computer vision community

Real-time mosaicing of fetoscopic videos using SIFT

Fetoscopic laser photo-coagulation of the placental vascular anastomoses remains the most effective therapy for twin-to-twin transfusion syndrome (TTTS) in monochorionic twin pregnancies. However, to ensure the success of the intervention, complete photo-coagulation of all anastomoses is needed. This is made difficult by the limited field of view of the fetoscopic video guidance, which hinders the surgeon’s ability to locate all the anastomoses. A potential solution to this problem is to expand the field of view of the placental surface by creating a mosaic from overlapping fetoscopic images. This mosaic can then be used for anastomoses localization and spatial orientation during surgery. However, this requires accurate and fast algorithms that can operate within the real-time constraints of fetal surgery. In this work, we present an image mosaicing framework that leverages the parallelism of modern GPUs and can process clinical fetoscopic images in real-time. Initial qualitative results on ex-vivo placental images indicate that the proposed framework can generate clinically useful mosaics from fetoscopic videos in real-time