Choroidal blood flow II. Reflexive control in the monkey
L. M. Parver, C. R. Auker, D. O. Carpenter and T. Doyle
Temperature measurements were taken from (1) the retina-choroid in the
macula, (2) the scleral surface, or (3) the bulbar conjunctiva of the
cynomolgus monkey, while the fellow eye was exposed to a moderate-intensity
light source. Light stimulation produced an increase in tissue temperature
in the non-light-stimulated eye. The increase in tissue temperature
presumably results from a reflexive increase in choroidal blood flow.
Hydrogen washout measurements of blood flow in the retina-choroid confirmed
this increase in flow. This active mechanism, along with the passive
ability of the choroidal circulation to dissipate light-generated heat, may
be an important physiologic safeguard in helping to maintain a stable
temperature environment for the outer retinal layers in the macula.
