ABSTRACT
Diagnosis of and differentiation among the vasculitides remains squarely based on a detailed clinical history, thorough physical examination, and appropriate laboratory testing. Of these, the physical examination and clinical history will usually form the basis of diagnosis (1). Laboratory testing (i.e., serological acute phase reactants and hematological parameters) may be of benefit when results are abnormal; however, the results are often misleading and do not correlate with disease activity in 50% of patient encounters (2-4). This chapter focuses on the contribution noninvasive imaging provides in differentiating the vasculitides and defining the extent of disease, and discusses new techniques that may provide unique information in defining disease activity and guiding therapy.
