ABSTRACT
The eye offers a unique opportunity to study hemodynamics. It is the only location in the body where capillary blood flow may be observed in humans noninvasively. The retrolaminar region has two blood supplies: the central retinal artery and the pial system. Ocular blood flow in healthy individuals is auto-regulated to maintain constant flow to sensitive ocular tissues despite fluctuating blood pressure and intraocular pressure (IOP). The Canon laser blood flowmeter is the only hemodynamic assessment device capable of measuring volumetric blood flow in absolute units in larger vessels. The pulsatile ocular blood flow device is a pneumotonometer that measures IOP and derived ocular pulse amplitudes in real time. When blood flow ceases within a vascular bed, its contribution to the IOP waveform measured by the pneumotonometer disappears, this allows direct quantification of the perfusion pressure within the uveal and retinal beds.
