Thousands of exoplanets have been discovered in the past 20 years using the radial velocity and transit techniques. But these techniques are at present limited to the detection of companions within a few astronomical units. This thesis aims at probing the giant planet and brown dwarf distribution on wider orbits. This goal is reached by combining the radial velocity and direct imaging techniques. An new data reduction pipeline called GRAPHIC has been developed in order to use the direct imaging technique. This pipeline was then used to analyse the observations taken with VLT/NACO of target who had a radial velocity trend. A statistical analysis of the observed sample was then used to derive the distribution of brown dwarfs on wide orbits. The thesis ends with the presentation of preparatory work for the oncoming observations with the new instrument SPHERE.