Introduction

In this chapter, we speculate on future developments that are expected to improve our ability to characterize carotid atherosclerotic plaque. To this end, we first introduce the term magnetic resonance (MR) “virtual histology” as a way of organizing our thoughts about these future developments. Then we discuss some technological advancements that should eventually allow MR “virtual histology” of atherosclerosis to become a reality, and the impact that these novel technologies will have on our ability to diagnose and treat atherosclerosis.

MR virtual histology and atherosclerosis

The “gold standard” of tissue identification used in pathology is the histological staining of sections of fixed tissue from the organ of interest. Histology utilizes specific stains to differentiate between tissues, thus separating tissue types with contrasting colors. For example, to identify collagen, we use a stain that is sensitive to the chemical structure of collagen. Histological analysis of atherosclerotic plaque often involves the comparison of normal or asymptomatic tissue to tissue from patients presenting with clinical symptoms, and the subsequent identification and interpretation of any structural or compositional differences between these tissue types that may explain the clinical symptoms.

Of all the clinical imaging modalities used today, magnetic resonance imaging (MRI) is the most effective and flexible at providing contrast between different tissue types. It does this by probing the chemical environment (i.e. density, chemical and physical state of hydrogen nuclei) of different tissues.