Bilateral Third Eyelid Ectopic Cilia in a Maine Coon Cat

To describe a case of a Maine Coon cat diagnosed with bilateral aberrant hairs consistent with ectopic cilia arising from the third eyelid.

The history, clinical signs, examination findings, surgical procedures, and case outcome were reviewed.

An eleven-month-old Maine Coon cat presented with a chronic history of bilateral epiphora and right blepharospasm. The left eye previously underwent upper and lower eyelid wedge excision to shorten the palpebral fissure and a partial Celsus-Hotz procedure to correct lower eyelid entropion. The right eye developed lower eyelid entropion shortly after and was surgically treated using the Read and Broun technique. Examination revealed a bilateral ocular discharge and follicular conjunctivitis; macroblepharon, permanent lower eyelid entropion associated with trichiasis, and non-ulcerative keratitis were present in the right eye. The upper and lower eyelid position was normal in the left eye. The right eye was treated with the Stades Diabolo technique and a partial Celsus-Hotz procedure. Inspection under general anesthesia revealed bilateral single aberrant hairs consistent with ectopic cilia on the palpebral surface of the third eyelid. A focal conjunctivectomy, including the ectopic cilium, was performed in each eye. Eyelid and conjunctival wounds healed uneventfully.

Differential diagnoses for aberrant hair arising from the third eyelid conjunctiva include dermoid, choristoma, or ectopic cilium. Histology was declined due to financial constraints. Although not previously reported in the literature, given the clinical appearance, an ectopic cilium is the most likely diagnosis. Surgical excision was curative, with no recurrence of epiphora, conjunctivitis, or the entropion.