Scleral Ring

Ring of bone supporting the eye

The scleral ring is a hardened ring of plates, often derived from bone, that is found in the eyes of many animals in several groups of vertebrates. Some species of mammals, amphibians, and crocodilians lack scleral rings. The ring is in the fibrous outer layer of the eye, called the sclera. The structure is commonly referred to as the sclerotic ring; but, because the word sclerotic often implies pathology of the sclera, recent authors have urged avoiding the use of this term, to avoid confusion and to increase the utility of character comparisons.

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