Lymphatic sinus-like structures in choroid.

Lymphatic sinus-like structures were demonstrated in the choroid of the monkey eye by transmission and scanning electron microscopy. These lymphatic sinus-like structures were lined by fibroblast-like cells with large intercellular gaps. When the specimens were viewed by scanning electron microscopy, the surface morphology of the fibroblast-like cells was similar to that of the endothelial cells of blood vessels or lymphatic vessels. Some fibroblast-like cells possessed intracellular fenestrations which varied in size, number and distribution. It is suggested that the lymphatic sinus-like structures here observed might play a role in the drainage of fluid from the choroid.