A dermoid is a choristoma, wich is a congenital mass of
tissue in na abnormal position. Dermoids usually occur at the temporal limbal área,
and they generally extend onto the sclera and the cornea. These lesions contain
keratinied epithelium, hair, blood vessels, fibrous tissue, fat, nerves,
glands, smooth muscle, and even cartilage. Dermoids are presente at birth but
may not be recognized clinically until the animal is several weeks old.
Dermoids are removed by superficial keratectomy and removal of the adjacente,
Essentials of Veterinary Ophthalmology, Kirk Gellat, 2000