Studv on macrophage imaging of atherosclerotic plaque using 2-Color Optical Coherence Dosigraphy

Abstract

Recently, optical coherence tomography (OCT) has been applied to cardiovascular diagnostic imaging of atherosclerotic plaques as a microscale tomographic visualizing technique. However, it is quite difficult to detect the vulnerability associated with macrophage invasion into plaques. Previously, we proposed 2-Color Optical Coherence Dosigraphy (2C-OCD), which can visualize tomographic images of photosensitizer infiltration. In this study, we propose a macrophage diagnosing technique by employing 2C-OCD and selective uptake of photosensitizer to lipidrich plaques and macrophages. In order to evaluate the bioavailability, 2C"OCD was applied to atherosclerotic rabbits aorta with photosensitizer AlPcS administrated. Comparing between AlPco infiltration visualized by 200CD and their histological images, AlPcS infiltration was only observed to increase at plaque lesion with significance /7<0.001. In addition, AlPcS accumulation appeared to be similar to macrophage invasion obtained by RAM 11 immuno-staining. Consequently, 2C-OCD has a promising diagnostic modality to detect macrophage invasion as well as the vulnerability of atherosclerotic plaques.