Barrera, D.F., Pestana, R.C. and Vivas, F.A., 2013. Pseudo-acoustic wave equation for modeling and reverse time migration in TTI media. Journal of Seismic Exploration, 22: 33-48. In recent years there has been a growing interest in the use of wave equations with anisotropy in the imaging of seismic data, due to the need to improve exploration and seismic data processing. Laboratory studies have indicated with convincing evidence that thin layers of shale introduces a polar anisotropy in the medium, which depends on the inclination of the layers with respect to an axis of symmetry. If the effect of anisotropy is not taken into account in the imaging procedure, the migrated section will present mispositioned reflectors. To incorporate the effects of anisotropy in the seismic imaging, many migration algorithms based on the ray theory and on the solution of the wave equation, have been adapted from the isotropic case. Therefore, conventional methods of migration, including the reverse time migration, are prone to errors with some kinds of anisotropy in the medium, thus producing low resolution images and seismic mispositioned reflectors. Consequently, to produce images used to delineate reservoirs, for example, methods of migration that take into account the anisotropy of the medium must be implemented. In this work we derive P-wave equations for TTI media starting from the exact dispersion equation for TTI media proposed by Tsvankin (1996). These new dispersion equations are valid for 6 > € (Thomsen’s parameters) and strong anisotropy. Using the new equations for pure P-wave for TTI media, we migrated the BP-TTI synthetic data set with RTM technique using the rapid expansion method (REM). It significantly improved the migrations sections when compared with migrations that did not take into account the anisotropy of the medium.