Biomedical subjects

P Meseure

Publications and source records attributed to P Meseure.

3 recordsLinked to original sources

PubMed2004

A layered model of a virtual human intestine for surgery simulation.

In this paper, we propose a new approach to simulate the small intestine in a context of laparoscopic surgery. The ultimate aim of this work is to simulate the training of a basic surgical gesture in real-time: moving aside the intestine to reach hidden areas of the abdomen. The main problem posed by this kind of simulation is animating the intestine. The problem comes from the nature of the intestine: a very long tube which is not isotropically elastic, and is contained in a volume that is small when compared to the intestine's length. It coils extensively and collides with itself in many places. To do this, we use a layered model to animate the intestine. The intestine's axis is animated as a linear mechanical component. A specific sphere-based model handles contacts and self-collisions. A skinning model is used to create the intestine's volume around the axis. This paper discusses and compares three different representations for skinning the intestine: a parametric surface model and two implicit surface models. The first implicit surface model uses point skeletons while the second uses local convolution surfaces. Using these models, we obtained good-looking results in real-time. Some videos of this work can be found in the online version at doi: 10.1016/j.media.2004.11.006 and at www-imagis.imag.fr/Publications/2004/FLAMCFC04.

Algorithms↗

PubMed1998

[SPIC: a training simulator for coelioscopic interventions with gynecologic purpose].

There is much demand for laparoscopy training. We have developed a training simulator for initial training in gynecological laparoscopy. The simulator includes a mannequin with 3 located trocars, a PC and software for managing the graphical part of the training protocol. The objective is to learn how to achieve spatial localization and handle tools within the abdominal cavity. A series of exercises are proposed with increasing degree of difficulty. The simulator can be customized to simulate many different scenarios. The trainer must be present to provide an ultimate assessment of the trainee's experience. This new training tool cannot replace traditional surgical training but can help make it more efficient. The simulator is now being used by residents. Further technical developments are in progress to add further indispensable mechanical interactions (force feed back) to visualize the organ deformations and organ dissections within the abdominal cavity.

Computer Simulation↗

PubMed1995

Simulator for laser photocoagulation in ophthalmology.

The practice of laser photocoagulation plays a major role in the ocular therapy, but the persistence of many postoperative complications denotes genuine difficulty in mastering the technique. The authors present a device which, thanks to the use of simulation, enables actual practice to be dissociated from apprenticeship. While complying with the constraints of realism with regard to habitual conditions of laser use, the device offers access to a wide variety of clinical situations. The apparatus is built around the traditional instrument. A virtual image of the fundus is produced in real time from the sensors which detect the actual gestures used. The calculations make use of textured geometrical models. Digitized color photographs are organized to form a database which reflects the diversity of pigmentations and pathologies. A software interface has been developed to facilitate the use of the device. The prototype is operated using a PC-compatible computer; it displays the images at the rate of at least seven per second on a miniature CGA screen incorporated in the slit-lamp. It is currently being validated for clinical applications. Above and beyond apprenticeship in laser photocoagulation, its potential applications extend to the entire field of ophthalmogical symptomatology and, more broadly, to the simulation of any examination conducted with the help of binocular or endoscopic optics.

Computer Simulation↗