CHOROIDAL BLOOD FLOW IN LEFT AND RIGHT EYES DURING TRANSIENT UNILATERAL VASCULAR STRESS

Title CHOROIDAL BLOOD FLOW IN LEFT AND RIGHT EYES DURING TRANSIENT UNILATERAL VASCULAR STRESS
Author, Co-Author Helene Kergoat
Topic
Year
1992
Day
Monday
Program Number
Poster 34
Room
Great Hall
Affiliation
Abstract Kergoat and Lovasik (1990) reported that a transient decrease in ocular perfusion pressure (OPP) decreased the neural function in the test eye but increased responsivity in the contralateral untouched (control) eye. This was hypothesized to be due to some mechanism which compensated for the unilateral vascular stress by increasing blood flow to that eye and causing a concomitant hyper-perfusion of the contralateral eye. In the present study the possibility that variations of the pulsatile ocular blood flow (POBF) may contribute to the contralateral phenomenon was investigated. Twenty volunteers (20 to 43 yrs of age) with normal intraocular (IOP) and brachial BP were used as subjects. The OPP was decreased in the test (right) eye by scleral suction (SS). A Langham OBF system was used to record the POBF for baseline, and also during a 20% and 40% decrease in the OPP. Four POBF readings were taken for each eye at baseline OPP levels and after the OPP in the test eye alone was reduced by 20% and 40% each for a 2 min. period. The group averaged data showed a progressive decrease in the POBF in the test eye during decreasing OPP (p= 0.0001). No change was found for the POBF for the control eyes (p= 0.7542). Within the limitations of the systems and testing employed, it is concluded that the contralateral changes in neural function reported by Kergoat and Lovasik (1990) cannot be explained solely by variation of the POBF in that eye. Other strategies for assessing the nature of this phenomenon are discussed.
Affiliation of Co-Authors
Outline