Epipolar geometry for vision-guided laser surgery.

International audienceThe μRALP project involves the development of a system for endoluminal laser phonosurgery, i.e. surgery of the vocal chords using a laser emitted from inside the larynx. Indeed, in current laryngeal laser surgical procedures, a beam of incision laser is projected on the target position of the soft tissue from the working distance of 400mm by means of a rigid laryngoscope (Fig.1). This yields safety concerns for the patient and staff, as well as limitations to accuracy. More, this so-called laryngeal suspension position of the patient requires an extreme extension of the neck, which makes it painful several days after the operation

Improving ultrasound intensity-based visual servoing: tracking and positioning tasks with 2D and bi-plane probes

International audienceReal time and non invasive, the ultrasound imag- ing modality can easily be used in minimally invasive surgery or needle insertion procedures to visualize an organ or a tumor to reach. However the manual stabilization of the ultrasound image while the organ moves with patient breathing or heart beating can be very tricky. In this paper, we present an intensity-based approach to control both in-plane and out- of-plane motions of an ultrasound probe held by a robotic arm in order to reach and follow one organ cross section. Two methods are proposed to improve the accuracy of this intensity-based approach, by estimating on-line the 3D image gradient required in the control law and by considering a bi-plane sensor. Robotic experiments are performed with two different ultrasound sensors on a realistic abdominal phantom and validate this visual servoing approach

Robotic Ultrasound Imaging: State-of-the-Art and Future Perspectives

Ultrasound (US) is one of the most widely used modalities for clinical intervention and diagnosis due to the merits of providing non-invasive, radiation-free, and real-time images. However, free-hand US examinations are highly operator-dependent. Robotic US System (RUSS) aims at overcoming this shortcoming by offering reproducibility, while also aiming at improving dexterity, and intelligent anatomy and disease-aware imaging. In addition to enhancing diagnostic outcomes, RUSS also holds the potential to provide medical interventions for populations suffering from the shortage of experienced sonographers. In this paper, we categorize RUSS as teleoperated or autonomous. Regarding teleoperated RUSS, we summarize their technical developments, and clinical evaluations, respectively. This survey then focuses on the review of recent work on autonomous robotic US imaging. We demonstrate that machine learning and artificial intelligence present the key techniques, which enable intelligent patient and process-specific, motion and deformation-aware robotic image acquisition. We also show that the research on artificial intelligence for autonomous RUSS has directed the research community toward understanding and modeling expert sonographers' semantic reasoning and action. Here, we call this process, the recovery of the "language of sonography". This side result of research on autonomous robotic US acquisitions could be considered as valuable and essential as the progress made in the robotic US examination itself. This article will provide both engineers and clinicians with a comprehensive understanding of RUSS by surveying underlying techniques.Comment: Accepted by Medical Image Analysi

Quoi de neuf en asservissement visuel depuis les JNRR'03 ?

National audienceCet article de synthèse présente les avancées réalisées en France au cours de ces quatre dernières années dans le domaine de l'asservissement visuel

Neurosurgical Ultrasound Pose Estimation Using Image-Based Registration and Sensor Fusion - A Feasibility Study

Modern neurosurgical procedures often rely on computer-assisted real-time guidance using multiple medical imaging modalities. State-of-the-art commercial products enable the fusion of pre-operative with intra-operative images (e.g., magnetic resonance [MR] with ultrasound [US] images), as well as the on-screen visualization of procedures in progress. In so doing, US images can be employed as a template to which pre-operative images can be registered, to correct for anatomical changes, to provide live-image feedback, and consequently to improve confidence when making resection margin decisions near eloquent regions during tumour surgery. In spite of the potential for tracked ultrasound to improve many neurosurgical procedures, it is not widely used. State-of-the-art systems are handicapped by optical tracking’s need for consistent line-of-sight, keeping tracked rigid bodies clean and rigidly fixed, and requiring a calibration workflow. The goal of this work is to improve the value offered by co-registered ultrasound images without the workflow drawbacks of conventional systems. The novel work in this thesis includes: the exploration and development of a GPU-enabled 2D-3D multi-modal registration algorithm based on the existing LC2 metric; and the use of this registration algorithm in the context of a sensor and image-fusion algorithm. The work presented here is a motivating step in a vision towards a heterogeneous tracking framework for image-guided interventions where the knowledge from intraoperative imaging, pre-operative imaging, and (potentially disjoint) wireless sensors in the surgical field are seamlessly integrated for the benefit of the surgeon. The technology described in this thesis, inspired by advances in robot localization demonstrate how inaccurate pose data from disjoint sources can produce a localization system greater than the sum of its parts

A System for 3D Ultrasound-Guided Robotic Retrieval of Foreign Bodies from a Beating Heart

Abstract²By way of the venous system or direct penetration, particles such as thrombi, bullet fragments, and shrapnel can become trapped in the heart and disrupt cardiac function. The severity of disruption can range from asymptomatic to fatal. Injuries of this nature are common in both civilian and military populations. For symptomatic cases, the conventional approach is removal of the foreign body through open heart surgery, which comes with high perioperative risks and a long recovery period. To circumvent these disadvantages, we propose a minimally invasive surgical approach for retrieving foreign bodies from a beating heart. This paper describes the first use of 3D transesophageal echocardiography (TEE) for steering a robot. Experiments demonstrate the feasibility of using 3D ultrasound to both guide and track a robot as it pursues a foreign body, with an RMS error of 1.6 mm in a laboratory setup. Results also support the hypothesis that direct pursuit of the foreign body may exceed the capabilities of conventional surgical robots, necessitating alternate retrieval strategies