Scleritis can cause permanent damage to the eye and vision loss. In most cases, the inflammation begins in one area and spreads until the entire sclera is involved. This pain tends to worsen with eye movements. Generally, the onset of scleritis is gradual, and most patients develop severe, piercing eye pain over several days. Up to 50% of cases of scleritis involve an underlying systemic disease, such as rheumatoid arthritis. Scleritis is a more serious and typically more painful red eye than episcleritis. This is inflammation of both the episclera and the underlying sclera itself. Oral pain medication and refrigerated artificial tears may be recommended if discomfort is a problem. Most episodes of episcleritis will resolve on their own within two to three weeks. Certain eye infections may also be associated with episcleritis. The cause of most cases of episcleritis is unknown, but a significant minority (up to 36%) of people who get the eye condition have an associated systemic disorder, such as rheumatoid arthritis, ulcerative colitis, lupus, rosacea or gout. Simple episcleritis, where dilated episcleral blood vessels occur without the presence of a nodule. Nodular episcleritis, where redness and inflamed tissue occur on a discrete, elevated area overlying the sclera. Episcleritis is relatively common and tends to be benign and self-limiting. This is inflammation of the episclera that lies atop the sclera and under the conjunctiva. Acquired diseases such as iron deficiency anemia can also be associated with blue sclera.Įpiscleritis. Blue sclera is caused by a congenitally thinner-than-normal sclera or a thinning of the sclera from disease, which allows the color of the underlying choroidal tissue to show through it.Ĭongenital and hereditary diseases associated with blue sclera include osteogenesis imperfecta (brittle bone disease) and Marfan's syndrome (a connective tissue disorder). As you would expect, this condition is when a normally white sclera has a somewhat blue color. If you develop yellow eyes, you should have blood tests to see if you have this condition and associated liver problems.īlue sclera.
Increased blood serum levels of bilirubin (an orange-yellow pigment formed in the liver) is commonly associated with scleral icterus. Despite this, many eye care professionals continue to call yellow eyes or yellowing of the eyes "scleral icterus" because it's the color of the underlying white sclera that is altered by the condition. Some researchers have stated that the yellowing of the eyes (jaundice) actually takes place in the conjunctiva, not the sclera itself, and that the condition should therefore be called conjunctival icterus instead. There is some controversy about the accuracy of the name of this condition. It is associated with hepatitis and other liver diseases. This condition - also called icteric sclera - is a yellowing of the white of the eye.
Here are a few conditions that can affect the sclera: The sclera also provides a sturdy attachment for the extraocular muscles that control the movement of the eyes. The tough, fibrous nature of the sclera protects the eye from serious damage - such as laceration or rupture - from external trauma. The sclera and the intraocular pressure (IOP) of the eye maintain the shape of the eyeball. Other nourishment of the sclera comes from the underlying choroid, which is the vascular layer of the eyeball that is sandwiched between the sclera and the retina. Larger episcleral blood vessels are visible through the conjunctiva. Some of the nourishment of the sclera comes from the blood vessels in the episclera, which is a thin and loose connective tissue layer that lies on top of the sclera and under the transparent conjunctiva that covers the sclera and episclera. Some blood vessels pass through the sclera to other tissues, but the sclera itself is considered avascular (lacking blood vessels). The sclera is relatively inactive metabolically and has only a limited blood supply. The random arrangement and interweaving of these connective tissue fibers are what account for the strength and flexibility of the eyeball. It is composed of fibrils (small fibers) of collagen that are arranged in irregular and interlacing bundles. The sclera ranges in thickness from about 0.3 millimeter to 1.0 millimeter. The junction between the white sclera and the clear cornea is called the limbus.
It is continuous with the stroma layer of the cornea. The sclera is the dense connective tissue of the eyeball that forms the "white" of the eye. Only a small portion of the anterior sclera is visible. In fact, the sclera forms more than 80% of the surface area of the eyeball, extending from the cornea all the way to the optic nerve, which exits the back of the eye. The sclera is the white part of the eye that surrounds the cornea.
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