CLINICALCLINICAL VIEW VIEW hh OPHTHALMOLOGYOPHTHALMOLOGY hh PEERPEER REVIEWED REVIEWED

Distichiasis

Caryn Plummer, DVM, DACVO University of Florida

1 d Multiple distichiae of the upper and lower of a dog.

Distichiasis is the abnormal presence Clinical Signs of cilia (eg, ) in the Many cases are noted incidentally when an meibomian glands.1 ophthalmic examination is conducted. Oth- ers are diagnosed when the patient presents with mild-to-moderate ocular discomfort Distichia hair follicles are found in the base (eg, persistent or intermittent squinting, of the meibomian gland, where the cilia exit increased blinking frequency) and epiphora through its orifice; the cilia may contact the with or without tear staining on the face. and cause irritation. The majority of dogs with distichia do not require any treat- Diagnosis ment; however, in cases associated with dis- Distichia are usually noted when a thorough comfort, therapeutic intervention should be examination of the eyelid margins and ocular pursued. If the hairs emerge from the con- surface is performed. Some hairs are large or junctival surface as ectopic cilia, therapeutic numerous enough to be noticed by the naked removal is usually necessary. Distichiasis is eye; others require magnification to be thought to be inherited, but the mechanism observed (Figure 1, above; Figures 2 & 3, of transmission is unknown.2 next page).

Any individual patient may present with Treatment distichiasis; however, certain breeds are If hairs are soft and nonirritating, benign more prone to the condition: American and neglect is preferred; treatment, if not per- English cocker spaniels, Welsh springer formed with care, may result in irreversible spaniels, Cavalier King Charles spaniels, damage to eyelid margins and meibomian flat-coated retrievers, English bulldogs, glands, which could result in permanent shih-tzus, , dachshunds, and Parson eyelid deformity or qualitative tear film Russell terriers. deficiency.

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2 3

d A single or few solitary distichia are more d Multiple upper eyelid distichia in a dog. Note how commonly encountered than a great number. stubby and stiff a few appear.

The most common and, in general, least risky option is cryoablation of the hair- producing follicle. 4 5

d Cryotherapy for distichia is applied 3 to 4 mm d Formation of an iceball advancing across the behind the eyelid margin over the base of the meibomian gland openings. affected meibomian gland on the palpebral conjunctival surface. A double freeze–thaw to –25°C destroys follicles but spares adjacent tissue. It is strongly recommended that a The simplest treatment for distichia is man- chalazion clamp be used when performing ual epilation at regular intervals (ie, 4–6 cryoepilation, as it facilitates exposure and weeks) with smooth-tipped cilia forceps; assists with cryodestruction of the follicle by however, patients with clinical signs as a reducing blood flow to the gland, thereby result of the offending hairs are recom- speeding the freeze and slowing the thaw. mended to undergo for a more per- manent solution. To this end, a variety of surgical interventions are available. The most If the cilia cause discomfort or exacerbate common and, in general, least risky option is corneal erosions or ulcerations, surgical cryoablation of the hair-producing follicle removal or destruction of the distichia hair (Figure 4).3 Cryotherapy is usually performed follicle is warranted. with either a nitrous oxide or liquid nitrogen

40 cliniciansbrief.com March 2016 probe applied to the palpebral con- operative treatment should include junctiva over the affected meibo- systemic NSAIDs and topical corti- mian glands until an iceball forms costeroids. Eyelid and conjunctival that advances across the meibo- swelling after the procedure is mian gland openings (Figure 5). common; occasionally, eyelid The tissue is permitted to thaw depigmentation may occur. Other completely and treatment is surgical options include electro- repeated, followed by manual epila- epilation and surgical excision. tion of any visible distichia. The amount of time necessary to freeze Distichia are similar to other hairs the follicle varies with the cryogen or to cilia in that the hair follicle used and thickness of the patient’s undergoes a cycle of growth and INTRODUCING ALICAM® eyelid. shedding. Although hairs may not be present in other glands at the The simplest way to a thorough GI Pretreatment with a systemic time of treatment, they could consult. Administer ALICAM like a NSAID may minimize postopera- appear later and require additional pill and a board certified internist will tive swelling and discomfort. Post- treatment. n provide an assessment and complete treatment recommendations. With ALICAM on your shelf, there is always References an expert in your practice. 1. Bedford PG. Eyelashes and adventitious cilia Ophthalmology, 5th ed. Ames, IA: Wiley- as causes of corneal irritation. J Small Anim Blackwell; 2013:832-893. Pract. 1971;12(1):11-17. 3. Wheeler CA, Severin GA. Cryoepilation for the 2. Stades FC, van der Woerdt A. Diseases treatment of distichiasis in the dog and cat. and surgery of the canine eyelid. In: Gelatt JAAHA. 1984;20:877-884. KN, Gilger BC, Kern TJ, eds. Veterinary IMAGES ENTIRE GI TRACT

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