Described herein are compositions and methods for diagnosing, imaging, and quantifying non-calcified atherosclerotic plaque. Embodiments of compositions described herein comprise mannosylated dextran compounds along with other carbohydrate molecules comprising, for example, a diagnostic agent and a diagnostic moiety. The compounds and methods embodied herein produce superior localization and results for imaging, anatomically locating, and quantifying non-calcified atherosclerotic plaque.
