FIVHeMA: Intraventricular fibrinolysis versus external ventricular drainage alone in aneurysmal subarachnoid hemorrhage: A randomized controlled trial.

INTRODUCTION: Aneurysmal subarachnoid hemorrhage (SAH) is a devastating form of stroke, which often causes acute hydrocephalus requiring the insertion of an external ventricular drain (EVD). A major complication of aneurysmal SAH is delayed cerebral ischemia (DCI). As DCI is linked to the presence of blood within the subarachnoid space, it has been hypothesized that removing this blood may decrease the risk of DCI. This could be achieved by injecting a fibrinolytic agent through the EVD, a strategy called intraventricular fibrinolysis (IVF). Here, we propose to conduct a phase III trial to directly evaluate the impact of IVF after aneurysmal SAH. MATERIALS AND METHODS: We will perform an open-label randomized controlled trial comparing the standard of care, i.e. EVD alone, to the experimental treatment, i.e. IVF. We plan to include 440 patients to be able to show a 10% increase in the rate of good functional outcomes in the EVD+IVF group compared to the EVD alone group (α=0.05 and ß=0.8). To obtain such sample, a multicenter trial is required, and to date 17 research sites in France have agreed to participate. PERSPECTIVE: FIVHeMA would be the first phase III trial evaluating the relevance of IVF in aneurysmal SAH. If IVF is shown to be beneficial, then a new therapeutic tool will be available to improve the outcomes of aneurysmal SAH patients.

An experimental UHV AFM-STM device for characterizing surface nanostructures under stress/strain at variable temperature.

A compression setup fully integrated in an ultra high vacuum chamber is presented. The system has been designed to combine in situ mechanical test together with near field microscopy at variable temperature, from 90 to 600 K. Compressive stress can be applied on the samples up to 500 MPa at different strain rates ranging from 10(-6) s(-1) to 10(-2) s(-1). The setup performances are highlighted through investigations on Au and Ni3(Al,Ta) single crystals. In particular, it is demonstrated that the high mechanical stability of the original apparatus allows us to follow in situ the evolution of the same area of interest over a large range of temperature and to keep the high spatial resolution offered by near field microscopy, even at high strain levels.

Bimanual haptic workstation for laparoscopic surgery simulation.

Realistic laparoscopic surgical simulators will require real-time graphic imaging and tactile feedback. Our research objective is to develop a cost-effective haptic workstation for the simulation of laparoscopic procedures for training and treatment planning. The physical station consists of a custom-built frame into which laparoscopic trocars and surgical tools may be attached/inserted and which are continuously adjustable to various positions and orientations to simulate multiple laparoscopic surgical approaches. Instruments inserted through the trocars are attached to end effectors of two haptic devices and interfaced to a high speed PC with fast graphics capability. The haptic device transduces 3D motion of the two manually operated surgical instruments into slave maneuvers in virtual space. The slave instrument tips probe the simulated organ. Simulations currently in progress include: 1) Surface-only renderings, deformation, and haptic interactions with elements in the gall gladder surgical field; 2) Voxel-based simulations of the bulk manipulation of tissue; 3) laparoscopic herniorrhaphy. This system provides force feed-forward from the grasped tools to the contact tissue in virtual space, with deformation of the tissue by the virtual probe, and force feedback from the deformed tissue to the operator's hands.

Ring-laser gyro with spatially resolved eigenstates.

The spatial resolution of laser eigenstates is applied to ring geometry. A bidirectional optical diode based on the Faraday effect and nonreciprocal intracavity losses is theoretically and experimentally investigated. This novel optical diode combined with spatial separation provides a biased gyro with no lock-in band.

Toward a non-traumatic determination of the rheological properties of the vascular wall.

It is possible to show the existence of a biunivocal relationship, at a given time, between the longitudinal velocity profile of a pulsatile flow in a flexible tube on the one hand and the pressure gradient which induces the flow and the mechanical behavior of the wall on the other hand, for an assumed rheological model. From experimental data of velocity profiles, only pressure gradients can be correctly calculated. To determine the elasticity of the material, a theory is developed which requires a knowledge of the time dependence of the wall motion. This theory is tested first on numerically simulated velocity data then verified experimentally with a hydromechanical device.