Purpose. To investigate the source and protein content of subretinal f
luid in self-forming experimental serous retinal detachments. Methods.
Detachments were induced in Dutch rabbit eyes using rose bengal photo
sensitization to cause choriocapillaris injury and thrombosis. Serous
detachments formed spontaneously within the next 24 h. Subretinal flui
d was withdrawn 3, 8 and 24 hrs after photosensitization, and was anal
yzed for osmolality and albumin content by gel electrophoresis. Result
s. The albumin concentration in the subretinal fluid of light-induced
detachments was 68% of serum level at 3 h after light damage, and rose
close to serum level by 24 h. The osmolality of subretinal fluid 24 h
after light damage was essentially the same as serum and vitreous flu
id. Conclusions. The subretinal protein and fluid in light-induced det
achments in the central retina of the rabbit must come from the choroi
d, since there are no intrinsic retinal blood vessels in that region o
f the fundus. These data demonstrate that serous retinal detachments c
an form from choroidal fluid.