Using the POBF as an index of interocular blood flow effects during unilateral vascular stress

Kergoat and Lovasik [(1994). Ophthalmic and Physiological Optics, 14, pp. 401-407] reported that a transient decrease in ocular perfusion pressure (OPP) decreased the neural function in the test eye but increased the responsivity in the contralateral untouched (control) eye. Here the hypothesis tested was that a transient unilateral vascular stress would induce an increase in the Pulsatile Ocular Blood Flow (POBF) in the opposite eye. The POBF was measured in 20 healthy volunteers with normal intraocular pressure (IOP) and brachial blood pressure (BP). The OPP was decreased in the test (right) eye by scleral suction, and a Langham OBF system was used to make four readings of the POBF for each eye for baseline conditions, and when the OPP was decreased in the test eye alone by 20 and 40% for a 2 min period. Each individual, as well as the group averaged data showed a progressive decrease in the POBF in the test eye during a stepwise reduction in the OPP. No change was found for the POBF for the control eyes. Within the limitations of the systems and testing procedures employed, it is concluded that unilateral alterations in the OPP do not cause a change in the POBF in the contralateral eye.