Ophthalmoscopic appearances after injury to the circle of Zinn ANWAR

Concussion injury to the globe, if not severe enough to rupture the outer coat, causes a temporary expansion of the posterior sclera. This may pass unnoticed without producing any lesion, or may be severe enough to rupture the adjacent vascular structures. The circle of Zinn, by its particular situation around the optic nerve and within the sclera, is liable to such injury and its rupture is a possible cause of clinical appearances seen in some of the following eight cases. In the other cases there is probably a similar lesion of a short posterior ciliary artery or cilio-retinal vessel.