Summary:Mapping the surface area and distribution of atherosclerosis has so far required photographic, video, or photomicrographic imaging of the inner surface of the arterial wall, as well as laborious manual or sophisticated image processing methods of quantification. We investigated whether comparable results could be obtained by using a conventional flatbed scanner and readily available spreadsheet software. Lipid-rich lesions near 21 aortic branches from cholesterol-fed rabbits were mapped using a scanner-based technique and an established photomicrographic technique. When the tissue was counterstained and held on the scanner by a transparent weight to obtain adequate contrast and prevent detection of adventitial staining, the areas of lipid deposition detected by the two methods correlated highly (R 2 =0.99). Discrepancies arose mainly at the edges of lesions, probably because of alignment errors and better flattening of the tissue on the scanner; when these were accounted for, discrepancies occurred in <1% of the total area examined. The new method produces results comparable with previous procedures, but is much more rapid and requires only office equipment and software.