Adnexal surgery in dogs and cats

Abnormalities in eyelid position and function can lead to chronic irritation of cornea and conjunctiva. Corneal ulceration, vascularization and pigmentation are common consequences. Loss of vision, or loss of the globe may be the end result. The combination of ptosis and entropion of the upper eyelid is commonly seen in breeds with abundant forehead skin folds. Treatment options include surgical reduction of skin folds, suspending the brows, enforced secondary granulation of the upper eyelid, or a combination of procedures. Lid-shortening procedures reduce corneal exposure, improve functional blinking and reduce likelihood of traumatic proptosis. Although a lateral canthoplasty is technically easier to perform, a medial canthoplasty is the preferred method of eyelid shortening. An involuted lateral canthus with entropion is seen in certain dog breeds with a broad skull base and redundant facial skin. Surgical correction is by either applying traction to the lateral canthus, or by resection of the lateral canthal ligament. A combination of entropion, ectropion and macroblepharon may result in the presence of diamond shaped eyelids. Surgical correction involves the combination of several procedures. Upper eyelid agenesis is a congenital absence of part of the upper eyelid in cats. Treatment options include a skin-orbicularis flap from the lower eyelid with a conjunctival pedical graft, the transposition of the lower eyelid to the upper eyelid, cross lid flap and subdermal plexus flap, and subdermal collagen injection. Several techniques for reconstruction of upper and lower eyelid defects are described.