What is the sclera?
Apr 29, 2023
Source: Cainiu Health
Dr. Cui Xin
Introduction
The sclera is the outermost fibrous membrane of the eyeball, located in the posterior portion and accounting for approximately five-sixths of the outer layer of the eyeball wall. Composed of elastic fibers and dense collagen, the sclera is tough yet elastic, with a white appearance. It provides structural support for the contents of the eye, maintains the inherent shape of the eyeball, and preserves the optical function of the visual organ.
Under normal circumstances, the sclera refers to what is commonly known as the "white of the eye" and is part of the eyeball. The specific details are as follows:
The sclera is the outermost fibrous membrane of the eyeball, located in the posterior portion of the ocular wall and accounting for approximately five-sixths of the outer layer. Composed of elastic fibers and dense collagen, the sclera is tough yet elastic, with a white appearance. It provides structural support for the contents of the eye, helps maintain the eye's shape, and preserves the optical function of the visual system. The thickness of the sclera varies across regions: it is thinnest at the insertion points of the extraocular muscles, measuring about 0.3 mm, and thickest around the optic nerve and the corneoscleral limbus, reaching about 1 mm.
In general, scleral diseases often manifest as inflammation. Patients may be treated under medical guidance with corticosteroids or non-steroidal anti-inflammatory drugs administered either locally to the eye or systemically, such as indomethacin tablets or prednisone tablets. Scleral disease can also involve degeneration; however, the cause of scleral hyaline degeneration remains unclear, and usually no specific treatment is required. If patients experience discomfort or symptoms, they should seek medical care at a hospital promptly to prevent worsening of the condition.
