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.

[SOPHOCLE (Ophthalmologic Simulator of Laser PHOtocoagulation): contribution to virtual reality]. / SOPHOCLE (Simulateur Ophtalmologique de PHOtoCoagulation LaSer): contribution de la réalité virtuelle.

PURPOSE: This study was undertaken to teach laser retinal photocoagulation in different disorders using a "virtual eye". Most ophthalmologists routinely use laser photocoagulator. Both indications and laser effects are well-known. However, in various diseases (diabetic retinopathy, age-related-macular degeneration, myopia...) complications rate increase or at least does not decrease. The main reasons are: - ignorance of risk factors, - misuse of the instrument. METHODS: We developed a new automated device stimulating a real laser photocoagulator. Only slit-lamp exists. The three-mirror lens, the fundus and the retinal photocoagulation impacts are "virtual". CONCLUSION: The aim of the simulator is to help practitioners to recognize various pathologies almost as in real conditions and to be familiar with different technics of photocoagulation. By using computer assisted learning, a constant evaluation determines the level and the progress of practitioners.

[SPIC: a training simulator for coelioscopic interventions with gynecologic purpose]. / SPIC: simulateur pédagogique d'interventions coelioscopiques à visée gynécologique.

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.

[A teaching medical simulator: phacoemulsification in virtual reality]. / Simulateur pédagogique médical: la phacoémulsification en réalité virtuelle.

INTRODUCTION: Improvements in computer technology have made it possible to design a cataract surgery teaching simulator in real time. MATERIAL AND METHODS: A computed representation of the lens was made with a mechanical model simulating the behavior of the lens, to which we added texture. The different models use mesh to make a section, which allowed us to make a section in real time using element removal or separation. Different models were used: a mass-spring mesh, a rigid model and a deformable model created using the finite element method. The contact with the lens is simulated by a collision sphere, which provides the interaction between the surgical instruments and the virtual environment. The surgical instruments viewed on the screen are controlled by a stylus with 6 degrees of freedom. DISCUSSION: We obtained the first step of phacoemulsification in real time with a good visual aspect. The surgeon views the procedure and can modify his movements instantaneously. This simulator provides the opportunity for students to safely learn phacoemulsification and improve their technique with an infinite number of procedures. CONCLUSION: The realism offered by this tool provides a rigorous teaching tool that might reduce the learning curve for phacoemulsification.