Introduction

• Overflow of tears from the eye.
• A common problem.
• Cause: increased lacrimation and/or impaired tear drainage.
  Any animal presenting with epiphora should be carefully examined for evidence of ocular inflammation or pain.

Pathogenesis

Etiology

• Absence/aplasia of the lower punctal opening is the most common congenital disorder in dogs.
• Micropunctum will also result in epiphora.
• Nasal lower eyelid entropion Entropion.

Specific

• Breed.

Pathophysiology

• Results from a painful or irritant stimulus.

• Congenital problems include absence of the lower punctal opening and micropunctum Micropunctum.
• Breeds such as the Poodle (Miniature Poodle: miniature , Standard Poodle: Standard and Toy Poodle: Toy ), Shih Tzu Shih Tzu and Pekingese Pekingese may present with epiphora in the presence of a normal nasolacrimal system.
• Acquired obstructions of the drainage system may result from symblepharon Symblepharon , foreign bodies and space occupying lesions.

• The combination of tight lower eyelids, prominent globes with a shallow medial canthal lake and the wicking action of hairs at the medial canthus leads to epiphora although the nasolacrimal system is patent.

• Symblepharon may follow severe conjunctivitis Conjunctivitis.
• The presence of foreign bodies in the nasolacrimal duct may cause dacryocystitis Dacryocystitis.
• Neoplasia Eyelid: neoplasia.
• Epiphora can occur from a physiological not an anatomical nasolacrimal blockage in some breeds, eg Poodle, Shih Tzu.

Timecourse

• Dependent on etiology - congenital predisposition may show symptoms from time of birth.

Diagnosis

Treatment

Outcomes