Corneal dermoid in the puppy: what it is and how to treat it
4-month-old German Shepherd puppy with epiphora and mild blepharospasm in the left eye since adoption. At the temporal limbus there is a raised, pigmented lesion with hairs growing from its surface and rubbing the cornea. Fluorescein negative.
What is the lesion and how is it treated?
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A. A dermoid (choristoma): normal skin tissue in an abnormal location; it is removed by superficial keratectomy (and conjunctivectomy if the conjunctiva is involved)
Correct. It is a benign congenital anomaly containing skin, hair follicles and glands. The hairs irritate the cornea and conjunctiva, so it is removed by superficial lamellar keratectomy, which is usually curative.
B. A limbal melanoma; it requires enucleation
Limbal melanoma occurs in adult dogs and does not bear hair. Hair in a puppy is typical of a dermoid, and enucleation would be disproportionate.
C. Early chronic superficial keratitis (pannus); lifelong topical corticosteroid
Pannus does not appear at 4 months and does not bear hair; it is a vascular, pigmented infiltrate advancing from the limbus. Corticosteroids do not remove a dermoid.
D. Periodically pluck the hairs from the lesion until the puppy has finished growing
The hairs regrow because the lesion contains follicles. Plucking gives only temporary relief and maintains the chronic irritation.
lightbulb Key takeaway
A dermoid is a congenital choristoma: it is most typical at the temporal limbus and may involve the cornea, conjunctiva or eyelid. Superficial keratectomy must remove it completely, as remnants of follicles can produce hair again.
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Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.