Corneal lacerations are seen most frequently in dogs and horses and infrequently in cats. Bites, self-inflicted trauma, and other accidents can partially or totally penetrate the cornea. Partial-thickness corneal lacerations are usually highly painful and require apposition with simple interrupted absorbable sutures to the healthy cornea. Excision of the lacerated section is not recommended.
For full-thickness corneal lacerations, signs usually include pain, blepharospasm, tearing, a corneal defect, and variable iris prolapse. Marked aqueous flare, hyphema, miosis, and distortion of the pupil are common. Often, the size of the iris prolapse is much larger than the underlying corneal laceration. Prognosis depends on size and position of the corneal laceration, other ocular tissue involvement, gender (horse), age of the animal, duration of the injury, and other systemic injuries. If the entire eye cannot be examined directly, B-scan ultrasonography is used.
The corneal laceration is apposed with simple interrupted 7-0 to 8-0 absorbable sutures. To provide additional protection and support, the sutured laceration may be covered with a third eyelid flap, bulbar conjunctival graft, or partial temporary tarsorrhaphy. Postoperative therapy to control the secondary iridocyclitis consists of topical and systemic antibiotics, systemic NSAIDs, and mydriatics. Postoperative complications include variable and often dense corneal scarring, cataract formation with posterior synechiae, secondary glaucoma, phthisis bulbus, and bacterial endophthalmitis.