| 
            
              | BASICS 
 OVERVIEWTrichiasis develops when hair arising from normal sites contacts the
          corneal or conjunctival surfaces. Distichiasis develops when cilia
          emerge from or near the meibomian gland orifices on the lid margin.
          These cilia may or may not contact the cornea. Ectopic cilia are
          single or multiple hairs that arise from the palpebral conjunctival
          surface several millimeters from the lid margin, most commonly near
          the middle of the superior lid.
 SIGNALMENT• Eyelash disorders are common in dogs and rare in cats.
 • Problems tend to occur most commonly in young dogs.
 • Any breed can be affected; however, some breeds are
          predisposed--breeds with prominent facial folds such as the pekingese,
          pug, and bulldog
 frequently have facial fold trichiasis; most cocker spaniels have
          distichiasis to some degree; ectopic cilia are more common than
          average in the dachshund, lhasa apso, and shetland sheepdog, among
          other breeds.
 SIGNS Trichiasis
          From Facial Folds• Nasal corneal vascularization and pigmentation
 • Blepharospasm
 • Epiphora
 Distichiasis• Asymptomatic in most animals.
 • If stiff, stout distichia are contacting the cornea,
          blepharospasm, epiphora,
          corneal vascularization, pigmentation, and ulceration may develop.
 Ectopic
          Cilia• Ocular pain
 • Severe blepharospasm
 • Epiphora
 • Often cause superficial corneal ulcers with a linear appearance
          (corresponding to lid movement) on the superior cornea. These ulcers
          are resistant to healing until the underlying problem is diagnosed and
          corrected.
 |  |  CAUSES AND
          RISK FACTORSIn most dogs, the disorder is related to facial conformation to breed
          predisposition, or it is idiopathic.
 
 DIAGNOSIS
 DIFFERENTIAL
          DIAGNOSISOther adnexal abnormalities (e.g., entropion),
          keratoconjunctivitis sicca, conjunctival foreign body, and infectious
          conjunctivitis should be ruled out. Diagnosis is made on the basis of
          direct observation of the abnormal cilia.
 CBC/BIOCHEMISTRY/URINALYSIS
          N/A OTHER
          LABORATORY TESTS N/A IMAGING
          N/A OTHER
          DIAGNOSTIC PROCEDURES N/A TREATMENT• Trichiasis can be managed conservatively in some animals. Keeping
          the periocular hair short may help; however, clipping the hair on
          facial folds may make it stiffer and more irritating. Surgical
          correction of adnexal abnormalities is indicated, such as entropion
          correction. Facial folds can be resected; however, a medial canthal
          closure is often a better procedure because it eliminates
          lagophthalmos and medial entropion as well as facial fold trichiasis.
 • Distichiasis is asymptomatic in most animals, and no treatment is
          indicated. When symptomatic, distichia can be treated surgically by
          cryotherapy, electrocautery or electroepilation, or resection from the
          conjunctival surface. Lid splitting techniques should be avoided
          because postoperative scarring can predispose to cicatricial entropion
          and impaired lid function.
 • Ectopic cilia should be treated surgically with an en-bloc
          resection of the cilia and associated meibomian gland. Cryotherapy can
          be used as the sole treatment method or as an adjunct after surgical
          resection.
 
 MEDICATIONS
 DRUGS AND
          FLUIDS• Medical treatment is rarely indicated; however, lubricant
          ointments are sometimes valuable when used to soften cilia and lessen
          irritation before surgical correction.
 • Peri-operative, topically applied antibiotics are recommended in
          animals undergoing surgery in an effort to minimize conjunctival flora
          in the surgical sites.
 CONTRAINDICATIONS/POSSIBLE
          INTERACTIONS N/A FOLLOW-UP• Regrowth of distichia is common because destructive procedures
          such as cryotherapy and electroepilation have to be done
          conservatively to minimize lid damage.
 • Animals that develop ectopic cilia are at risk for developing
          ectopic cilia at other locations.
 • Owners should be advised to have their animal rechecked if
          clinical signs recur.
 MISCELLANEOUS ReferenceGelatt KN. Veterinary ophthalmology. 2nd ed. Philadelphia: Lea & Febiger, 1991.
 Author Erin S. Champagne
 Web Page
 |