English: Tomographic cross-sections of an OPT-imaged, atherosclerotic aortic arch. After tomographic reconstruction, cross-sectional OPT images (excitation 425 nm with 40 nm band-pass; emission 475 nm long pass) can be animated for qualitative evaluation of vascular structure (in addition to quantitative measurement). In atherosclerotic aortic arches, presented in this way, the media and lumen of the ascending and descending aorta can be seen clearly and some lesion formation is apparent on the lesser curvature of the arch. This can be clearly distinguished from the vessel media and lumen. More severe lesion formation is present at the roots of right carotid and subclavian arteries, and throughout the length of the brachiocephalic artery. The position of each cross-section within the artery is indicated on the non-tomographic image inset left.