What is the sclera (white part of the eye)?

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From the Research

The white part of the eye is called the sclera, a tough, fibrous tissue that forms the protective outer layer of the eyeball, covering about five-sixths of the eye's surface, as described in the most recent study 1. The sclera is composed primarily of collagen and elastic fibers, giving it strength and flexibility to protect the delicate internal structures of the eye.

  • Its white appearance comes from its dense, opaque nature, which prevents light from entering the eye except through the transparent cornea at the front.
  • The sclera maintains the eye's shape and provides attachment points for the six extraocular muscles that control eye movement.
  • Blood vessels visible on the sclera are actually in the conjunctiva, a thin membrane covering the sclera. Some key points about the sclera include:
  • It is a vital structure that provides protection and support to the eye.
  • Changes in the color of the sclera, such as yellowing (jaundice) or redness (inflammation), can indicate various health conditions, making it an important diagnostic indicator during eye examinations, as noted in 2.
  • The sclera can be affected by various conditions, including scleritis, which is a potentially sight-threatening condition that can cause inflammation and damage to the sclera, as discussed in 3. Overall, the sclera plays a crucial role in maintaining the health and function of the eye, and any changes or abnormalities in the sclera should be evaluated and addressed by a healthcare professional, as emphasized in the most recent study 1.

References

Research

Scleral thinning causes, diagnosis, and management: A narrative review.

Contact lens & anterior eye : the journal of the British Contact Lens Association, 2023

Research

Scleral structure, organisation and disease. A review.

Experimental eye research, 2004

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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