Cover Story: Blo Od Flow Table 1. an Overview of the Most Common Ocular Blood Flow Technologies Separated by Physical Basis of Measurement

T he reduction of IOP remains the only course of action for primary openangle glaucoma (POAG), despite consistent observations of vascular risk factors such as low ocular perfusion pressure,1-4 vascular narrowing,5 and a higher incidence of risk factors associated with cardiovascular disease.6 As interest grows in a possible vascular role in the development of glaucoma, the number of articles on blood flow and glaucoma has increased steadily (Figure 1). Clinicians therefore need to understand the nature of the measurements of ocular blood flow as well as their advantages and limitations. This article reviews the physical basis for these measurements and the pros and cons of the techniques currently most prevalent in the literature. Table 1 summarizes all of the measurements.