Distichiasis and Ectopic Cilia


Distichiasis and ectopic cilia are considered relatively common inherited disorders of the canine eyelids in which abnormal hair growth occurs within the lids themselves. These hairs emerge from the openings of the oil glands present at the lid margins. They're called "distichia" should they protrude onto the outer edge of the eyelid and "ectopic cilia" if they poke painfully inwards.

Dogs affected may be extremely uncomfortable, as almost always occurs with ectopic cilia. They may also be completely unaffected, as are some dogs whose distichiasis does not actually cause hairs to rub painfully on the delicate and nerve-rich cornea.

With these genetic eyelid diseases, both eyes are typically affected.

Symptoms and Identification

Dogs with distichiasis and ectopic cilia typically present with uncomfortable eyes: tearing, blinking (blepharospasm), redness and secondary conjunctival infections are common first signs. Later signs, particularly commonplace with ectopic cilia, are consistent with corneal ulceration. Loss of vision due to corneal scarring and eye loss are typical sequelae if treatment isn't sought.

Affected Breeds

By far the most commonly abnormal eyelid hair-affected breed is the Shih Tzu.


Not all cases of distichiasis require treatment (should no discomfort ensue from the abnormal hairs) but almost all ectopic cilia cases will. By far the most recommended method used to treat both conditions involves a surgical procedure called "cryoepilation." During this anesthetic procedure abnormal hair follicles are frozen with a liquid nitrogen probe and the hairs are subsequently individually removed.

Cryoepilation has been found to be 85-90% effective for most breeds of dogs when treated after the age of 3. In some cases, however, (particularly for puppies and young dogs) hairs will regrow and the procedure must be repeated. It's also the case that Shih Tzus are more likely to experience hair regrowth post-operatively.

Veterinary Cost

The cost of cryoepilation can be quite high relative to many routine ophthalmic procedures. Though it's a relatively quick procedure, the equipment and expertise involved are both expensive propositions. Owners should expect to spend $1,500 to $2,000 for this procedure. Many ophthalmologists, however, will charge less for follow-up procedures, if hair regrowth occurs.


Affected dogs should not be bred. This recommendation is the mainstay of our prevention protocols for these two diseases.


Veterinary Ophthalmology, 4th ed., Gelatt KN, editor, Blackwell Publishing, Ames IA 2007.

Ophthalmic Disease in Veterinary Medicine, Martin CL, Manson Publishing, 2005.