Radiation induced accelerated atherosclerosis is a well known entity that occurs in different regions, according to the therapy delivered.It is usually begins to be clinically evident several years after the radiation incident, as there is sufficient functional reserve to these vessels.Our proposal is aimed to better characterize this side effect. For that purpose, we have chosen to study women who received radiation to the breast, in which part of the carotid in the irradiated side was in the high energy radiation field. We will use Intima Media Thickening ultrasound to study the pattern of atherosclerosis plaque formation in radiated carotid arteries as compared to non-irradiated carotid arteries in women who are receiving radiation therapy for breast cancer.