The Goblet Cells produce the precious mucin of the tear film which is important for the health of the eye and to prevent feeling eye pain.
The ocular surface is covered by two types of epithelium:
1. The conjunctival epithelium
2. The corneal epithelium
The conjunctiva is covered with mucin-secreting goblet cells mixed with non-goblet epithelial cells.
If we detect goblet cells on the cornea by confocal microscopy, it means the corneal epithelium is being overthrown by the conjunctiva (conjunctivalization of corneal epithelium) and limbal stem cell deficiency.
Also if we detect the lack of mucus in the tear because of damaged conjunctival goblet cells, we know there is a diseased tear surface, such as occurs in keratoconjunctivitis sicca, chemical burns, and chronic dry eye.
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