Other testing in glaucoma: Optic nerve blood flow i

The body of evidence to date does not yet support the suggestion that blood flow in the optic nerve should be routinely measured in glaucoma and glaucoma suspect patients. This is primarily due to the fact that no single blood flow device at present can simultaneously evaluate all the vascular beds relevant to glaucoma [1]. Also, the currently available methods provide limited information on quantitative blood flow. They typically measure some surrogate parameters that are assumed to reflect volumetric perfusion, such as vessel diameter, pulsatility and velocity of flow, or they extrapolate on change in blood flow as a result of a provocative test (including flicker stimulation, O₂ and CO₂ inhalation and cold pressor tests). Therefore, the ideal test to measure comprehensive ocular blood flow (OBF) in the routine patient is yet to be developed [1-3].