In the course of developing a training simulator for puncture, a novel approach is proposed to render in real-time the ultrasound (US) image of any 3D model. It is combined with the deformation of the soft tissues (due to their interactions with a needle and a probe) according to their physical properties. Our solution reproduces the usual US artifacts at a low cost. It combines the use of textures and ray-tracing with a new way to efficiently render fibrous tissues. Deformations are handled in real-time on the GPU using displacement functions. Our approach goes beyond the usual bottleneck of real-time deformations of 3D models in interactive US simulation. The display of tissues deformation and the possibilities to tune the 3D morphotypes, tissue properties, needle shape, or even specific probe characteristics, is clearly an advantage in such a training environment.