There are many fields in medicine and biology where optical coherence tomography (OCT) is starting to be used for diagnostics imaging. In our work, OCT imaging has been applied to obtain 3D structure and geometry of mouse aorta and atherosclerotic plaques in it. Differences in plaque formation have been detected between mice fed with cholesterol rich food, and mice kept on special diet. The results of OCT measurements have been confirmed with optical microscopy.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.