[Age-correlation of blood pressure induced myogenic autoregulation of human retinal arterioles in 40 volunteers].
OBJECTIVE
For the first time noninvasive measurement of the myogenic response of retinal arterioles is possible by the use of the Retinal-Vessel-Analyzer (RVA). This study investigates the influence of age on retinal autoregulation.


METHODS
In 40 healthy volunteers continuous measurement of a retinal arteriole over a 9-min period was performed. After a 3-min baseline measurement isometric exercise caused a rise in blood pressure of 15-30 mm Hg. During the last 3 minutes recovery was documented. Volunteers were split into a group of 20 younger (18-34 yrs.) and 20 older subjects (35-57 yrs.). For statistical analysis the Mann-Whitney test was used.


RESULTS
All volunteers showed a rise in blood pressure. Significant differences in the blood-pressure rise were followed by a myogenic response of 1% up to 10% vasoconstriction. An individual autoregulation-curve was defined with negative gradient. Significant differences between the younger and the older volunteers can be identified by this methodology.


CONCLUSIONS
Age has a significant influence on the myogenic response in human retinal arterioles. Age should be considered as a factor in clinical studies on retinal autoregulation.
Blum
M
M
Augenklinik der Friedrich-Schiller-Universität Jena.
Bachmann
K
K
Strobel
J
J
D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D002829:Choroid / Q000098:blood supply*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation / Q000379:methods; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012161:Retinal Artery / Q000502:physiology*; D018709:Statistics, Nonparametric; D014661:Vasoconstriction / Q000502:physiology