The goal of our work is to propose a fast ultrasound image simulation from CT volumes. This method is based on a model elaborated by Bamber and Dickinson that predict the appearance and properties of a B-Scan ultrasound image from the distribution of point scatterers. We propose to extend this model for the standard medical ultrasound image simulation by taking into account the acoustical tissue properties (scatterer distribution) and the geometry and the specifications of the ultrasound probe (circular probe, number and size of transducers, US pulse frequency and bandwidth, etc.). Simulations have been obtained in a fairly fast computation speed and qualitatively they present most of the real ultrasound image characteristics.